JP2012212019A - Method for manufacturing optical element array, optical element array, lens unit and camera module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an optical element array having an entirely homogeneous antireflection structure imparted thereto without degradation in the antireflection effect even in a high-temperature environment such as in a reflow process.SOLUTION: An optical element array 100 having a stable state of an antireflection structure 51 having a fine concavo-convex pattern can be manufactured. Specifically, as the antireflection structure 51 is formed of the same material as first and second optical faces 11d and 12d, the optical element array 100 can be manufactured without causing cracks and peeling in the antireflection structure 51 portion. As the entire surface of the optical element array 100 is uniformly irradiated with an ion beam having a controlled energy state, the antireflection structure 51 on the optical element array 100 can be made homogeneous.

Description

  The present invention relates to a method for manufacturing an optical element array, particularly for use in an imaging lens, an optical element array manufactured by the method, a lens unit manufactured using the optical element array, and a camera module.

  WLO (Wafer Level Optics) is a method for manufacturing a small number of small-sized camera lenses, such as a micro camera module, which stacks multiple lenses, CCD (Charge Coupled Device), CMOS (Complementary Metal Oxide Semiconductor), etc. Wafer level optics) technology (see, for example, Patent Documents 1 and 2). In the WLO technology, thousands of lenses are formed on a single wafer, and these wafers are cut after lamination, whereby a large number of lens units are manufactured without adjusting the axis. These lens units are combined with a CCD or the like and joined through a heat bonding process called reflow using solder to produce a camera module.

  Here, an optical lens generally used in a camera module is subjected to antireflection processing in order to reduce ghost and flare caused by surface reflection. As the most common antireflection processing, there is a method of providing an optical thin film called an antireflection film (see, for example, Patent Document 3). The antireflection film reduces reflected light by using interference of light. For example, a material having a lower refractive index than that of the lens material is applied to the lens surface at λ / 4 (where λ is a wavelength at which reflection is to be prevented). (If it is visible light, it is about 350 nm to 800 nm.) The reflection light is reduced by forming the film with a film thickness and acting to cancel the reflected light on the film surface and the reflected light on the lens surface. Let

As another antireflection process, there is a method of providing an antireflection structure having an antireflection function. The antireflection structure reduces reflection by forming a concave / convex shape of the wavelength scale of light and a portion having a small density when viewed macroscopically on the surface of an optical element such as a lens. As a method for producing the antireflection structure, there is a method in which a negative mold having an antireflection structure is produced in a mold for molding, and the antireflection structure is transferred at the time of molding (for example, see Patent Document 4). In addition, as a method for manufacturing the antireflection structure, there is a method in which after forming a film on the lens surface, the film is processed into an antireflection structure (see, for example, Patent Document 5). Here, in post-processing after film formation, there is etching using ion collision extracted from plasma and a plasma source (see, for example, Patent Document 6). Further, when producing a small optical element array such as an on-chip lens on an image sensor, an antireflection structure is produced by dry etching using oxygen (O ₂ ) on the surface of a flat layer provided on the microlens. There is also a technique to do this (for example, see Patent Document 7).

  However, in the methods of Patent Documents 3, 5, and 7, when placed under a high temperature called a reflow process, the film cracks or peels off due to the difference in the coefficient of linear expansion between the lens and the thin film. Problems can arise. In particular, when a resin is used as the lens material, the resin material has a larger expansion coefficient than that of the glass material, and problems such as cracking and peeling are more likely to occur when the resin material is placed at a high temperature, not limited to reflow.

  In addition, when a mold is used as a method for producing a structure as in the method of Patent Document 4, an optical element is inhomogeneous due to a defective mold release or a deterioration of the mold due to an increase in the adhesion area with the resin. There are problems such as the generation of metal molds, the mold fabrication becomes complicated and the cost becomes very high.

  Further, in plasma processing as in the method of Patent Document 6, it is necessary to keep the plasma density uniform with respect to the object to be processed. As a result, when an object having a relatively large area, such as an optical element array, becomes an object to be processed, the effect of the processing becomes uneven depending on the position in the optical element array. Therefore, it is difficult to obtain a uniform antireflection structure. In addition, in order to perform the plasma treatment uniformly, it is necessary to adjust the electrolytic distribution in the apparatus, and the design becomes difficult and the scale becomes large. In addition, when a thin film is deposited to form a mask layer, a protective layer, and the like before and after the etching process, two steps of plasma treatment and thin film deposition must be performed. Therefore, in addition to the transport and installation of the optical element array, it is necessary to evacuate both the plasma processing and the thin film deposition process, resulting in a problem that man-hours are required.

Special table 2010-519881 JP 2010-266815 A JP 60-129701 A JP 2005-31538 A JP 2010-48896 A US 2005-0233083 JP 2007-242771 A

  An object of the present invention is to provide a method for manufacturing an optical element array in which an antireflection effect is not deteriorated even under a high temperature environment such as a reflow process and a uniform antireflection structure is provided on the whole.

  It is another object of the present invention to provide an optical element array manufactured by the method for manufacturing an optical element array, a lens unit manufactured using the optical element array, and a camera module.

  In order to solve the above-described problems, a method for manufacturing an optical element array according to the present invention is a method for manufacturing an optical element array in which a plurality of resin optical elements having optical function portions are formed, and the molded optical element array A patterning step of forming a mask pattern on the optical function portion, and an etching step of providing an antireflection structure on the optical function portion by etching with an ion beam.

  According to the method for manufacturing an optical element array, it is possible to manufacture an optical element array in which the antireflection structure having a fine uneven shape is in a stable state. Specifically, since the antireflection structure is made of the same material as that of the optical function part, an optical element array in which the difference in linear expansion coefficient between the antireflection structure and the optical function part is small and cracks do not occur is produced. Can do. Further, since the antireflection structure is made of the same material as that of the optical function part, there is no interface between the antireflection structure and the optical function part. Therefore, it is possible to produce an optical element array in which peeling does not occur in the antireflection structure part. Further, since the ion beam whose energy state is controlled is emitted from the ion irradiation port and uniformly irradiated on the entire surface of the optical element array, the antireflection structure on the optical element array can be made uniform.

  In a specific aspect or aspect of the present invention, in the manufacturing method of the optical element array, in the etching step, a difference between the maximum etching rate and the minimum etching rate in the portion where the optical element of the optical element array is arranged is It is within 10% of the maximum etching rate. In this case, if the difference between the maximum etching rate and the minimum etching rate is within 10% of the maximum etching rate in the portion where the optical element of the optical element array is disposed, the optical rate It is possible to produce a lens having an antireflection effect substantially equivalent to the above.

  In another aspect of the present invention, the mask pattern of the optical function portion is formed in a fine island shape. In this case, the characteristics of the fine uneven shape of the antireflection structure can be easily adjusted by adjusting the arrangement and size of the pattern.

  In still another aspect of the present invention, an inert gas and a reactive gas are used in the etching process. In this case, the etching rate can be adjusted, and the characteristics of the fine irregular shape of the antireflection structure can be easily adjusted.

  In still another aspect of the present invention, a coating process is provided in which a protective layer for protecting the antireflection structure is provided on the antireflection structure after the etching process. In this case, the fine uneven shape of the antireflection structure can be protected from scratches, dust, dirt, and the like.

  In order to solve the above problems, an optical element array according to the present invention is an optical element array in which a plurality of resin optical elements having an optical function part are formed, and is formed by using an ion beam in the optical function part. And having a fine concavo-convex antireflection structure.

  According to the optical element array, the antireflection structure having a fine uneven shape provided on the optical element array is in a stable state. Specifically, since the antireflection structure is made of the same material as that of the optical function part, the difference in the linear expansion coefficient between the antireflection structure and the optical function part is small, and cracks do not occur. In addition, since the antireflection structure is formed of the same material as the optical function portion, there is no interface between the antireflection structure and the optical function portion, and no peeling occurs. Further, when forming the antireflection structure, the ion beam whose energy state is controlled is uniformly irradiated on the entire surface of the optical element array, so that the antireflection structure on the optical element array is uniform. Thereby, even when the optical element array is stacked and the cut optical element is incorporated into the camera module, the variation in the performance of the camera module can be suppressed small.

  In a specific aspect or viewpoint of the present invention, in the optical element array, the depth of the concavo-convex shape of the antireflection structure is 50 nm or more and 1000 nm or less. Here, the antireflection structure tends to have a tapered structure in which the volume density of the fine irregularities increases from the incident light side toward the optical element center side. In addition, the wavelength dependency is reduced by gradually changing the refractive index in the depth direction in the antireflection structure. Therefore, the optical function unit having the antireflection structure on the surface can reduce the angle dependency of incident light as compared with the antireflection film.

  In another aspect of the present invention, the resin has a heat resistance of 200 ° C. or higher. In this case, it is possible to suppress changes in the shape and color of the antireflection structure due to heat during reflow.

  In still another aspect of the present invention, the antireflection structure has a protective layer on the surface. In this case, the fine uneven shape of the antireflection structure can be protected from scratches, dust, dirt, and the like.

  In still another aspect of the present invention, the optical element is for guiding light to the imaging element itself having a plurality of photoelectric conversion elements. In this case, the optical element that guides light to the imaging device itself has a diameter of about 0.5 mm to 10 mm. The entire optical element array in which a plurality of such optical elements are formed is relatively large. Even when the optical element array becomes relatively large, an antireflection structure having uniform accuracy can be obtained by forming a uniform fine uneven shape as an antireflection structure using an ion beam.

  In order to solve the above problems, a lens unit according to the present invention includes an optical element separated from the optical element array.

  According to the above lens unit, a lens unit having high-precision optical performance is provided by using an optical element array that does not cause defects such as film peeling and cracks in the optical element and has a uniform antireflection structure. be able to.

  In order to solve the above problems, a first camera module according to the present invention is manufactured by combining an optical element separated from the optical element array and an image sensor.

  According to the first camera module, a camera module having high-precision optical performance by using an optical element array having a uniform antireflection structure without causing defects such as film peeling and cracks in the optical element. Can be provided.

  In order to solve the above problems, a second camera module according to the present invention is taken out from a combination of the optical element array and an image sensor array in which a plurality of image sensors are formed.

  According to the second camera module, a camera module having high-precision optical performance by using an optical element array having a uniform antireflection structure without causing defects such as film peeling and cracks in the optical element. Can be provided. Further, by combining a large number of image sensors and lens units at a time, the work process can be shortened compared to combining a single image sensor and lens units, so that the cost can be reduced.

  In order to solve the above problems, a third camera module according to the present invention is manufactured through a reflow process in a state where an optical element separated from the optical element array and an image sensor are combined.

  According to the third camera module, a high-precision optical device is used by using an optical element array having a uniform antireflection structure without causing defects such as film peeling and cracks in the optical element even after the reflow process. A camera module having performance can be provided. Moreover, the camera module adhered more firmly can be provided by passing through a reflow process.

(A) is a top view of the optical element array of 1st Embodiment, (B) is AA arrow sectional drawing of the optical element array shown to (A), (C) is (A). It is an expanded sectional view of the lens unit which laminated | stacked the optical element array to show and isolate | separated. It is the elements on larger scale explaining the reflection preventing structure of the optical element array of FIG. It is a conceptual diagram of the cross section explaining the shaping die used for manufacture of the optical element array of FIG. It is a conceptual diagram explaining the processing apparatus used for manufacture of the optical element array of FIG. (A)-(D) are the figures for demonstrating the shaping | molding process of the optical element array of FIG. It is a flowchart explaining the manufacturing process of the optical element array of FIG. (A) is a figure explaining the patterning process in the manufacturing process of the optical element array of FIG. 1, (B), (C) is a figure explaining an etching process, (D) is a coating process. FIG. It is sectional drawing explaining the camera module incorporating the lens unit of FIG.1 (C). It is a flowchart explaining the manufacturing process of the camera module of FIG. (A) is a figure explaining the camera module of 2nd Embodiment, (B) is a figure explaining the structure before cut | disconnecting the camera module of (A). It is a flowchart explaining the manufacturing process of the camera module of FIG. It is a figure explaining the optical element array of 3rd Embodiment.

[First Embodiment]
With reference to drawings, the optical element array which concerns on 1st Embodiment of this invention, the manufacturing method of an optical element array, etc. are demonstrated.

Optical Element Array As shown in FIGS. 1A and 1B, the optical element array 100 has a disc shape and includes a substrate 101, a first lens array layer 102, and a second lens array layer 103. . The optical element array 100 has a structure in which composite lenses 10 described later are integrated in a matrix. For convenience of explanation, only four compound lenses 10 are shown, but the actual optical element array 100 includes a large number of compound lenses 10. By laminating and separating the optical element array 100, post-processes such as axial alignment of the compound lens 10 can be shortened. Here, the first and second lens array layers 102 and 103 are bonded to the substrate 101 in alignment with each other with respect to translation in the XY plane perpendicular to the axis AX and rotation around the axis AX.

In the optical element array 100, the substrate 101 is a circular flat plate extending along the XY plane. The substrate 101 is formed of resin, glass, photonic crystal, and those obtained by adding an additive thereto. In particular, glass and transparent resin excellent in light transmittance, and those obtained by adding additives to these are preferable. The thickness of the substrate 101 is basically determined by optical specifications, but is such a thickness that the substrate 101 is not damaged when the optical element array 100 is released. Specifically, it is 0.25 mm or more and 1 mm or less, for example. The substrate 101 is used for the purpose of stabilizing the shape of the optical element array 100 and for the purpose of facilitating molding. The surface area of the substrate 101 is selected depending on the intended ^use, and has a range of 10cm ² ~20000cm 2. The surface area of the substrate 101 is preferably 100 cm ² or more in consideration of the number of first and second lens elements 11 and 12 described later formed on the substrate 101. Furthermore, the surface area of the substrate 101, considering the good handling 100 cm ² or more 2000 cm ² is more preferable. One or both surfaces of the substrate 101 may be subjected to surface treatment such as plasma, ion beam, polishing, heat treatment, dry etching, or wet etching according to the purpose such as cleaning or surface modification. Further, one or both surfaces of the substrate 101 may be subjected to processing such as protection film, resist processing, optical thin film deposition, etc., and surface processing and shape processing may be performed by cutting, molding, dicing, polishing, blasting, etc. It may be done. For example, patterning of the lens diaphragm can be performed by resist processing using a black resin material. In addition, by providing an infrared cut filter film on one or both surfaces of the substrate 101, noise to the image sensor can be reduced, and the performance of a camera module manufactured using the optical element array 100 can be improved. it can.

  The first lens array layer 102 is made of resin and is formed on one surface 101 b of the substrate 101. The first lens array layer 102 is formed so as to cover the entire surface of the substrate 101 in consideration of ease of molding. The first lens array layer 102 has a circular outer shape in plan view, and includes a large number of first lens elements 11. The first lens element 11 includes a first lens body 11a and a first flange portion 11b as a set. The first lens elements 11 are two-dimensionally arranged at equal intervals in the XY plane because of the ease of assembly of camera modules 70 and 270, which will be described later, and the homogeneity of the finished product. These first lens elements 11 are integrally molded through a flat connecting portion 11c. The shape of each first lens element 11 is substantially the same. The combined surface of the first lens element 11 and the connecting portion 11c is a first molding surface 102a that is collectively molded by transfer. The first lens body 11a is, for example, an aspheric lens part, and has a convex first optical surface 11d as an optical function part. The first optical surface 11d is an optical element, for example, for guiding light to the imaging element itself having a plurality of photoelectric conversion elements. In the case of this embodiment, the diameter of the first optical surface 11d is about 0.5 mm to 10 mm. The surrounding first flange portion 11b has a flat first flange surface 11g extending around the first optical surface 11d, and the outer periphery of the first flange portion 11b is also a connecting portion 11c. The first flange surface 11g is disposed in parallel to the XY plane perpendicular to the optical axis OA.

  As a material used for the first lens array layer 102, for example, a thermosetting resin, a photocurable resin, an organic-inorganic hybrid material, or the like is used. Specifically, examples of the photocurable resin include an acrylic resin, an allyl resin, an epoxy resin, and a fluorine resin, and examples of the thermosetting resin include a fluorine resin and a silicone resin. Examples of the organic / inorganic hybrid material include polyimide / titania hybrid. The material used for the first lens array layer 102 is preferably a thermosetting resin or an ultraviolet curable resin, particularly considering heat resistance and good workability. By using a resin having a melting point of 200 ° C. or higher, or a resin that is unlikely to deteriorate such as cracks when heated to 200 ° C. or higher, the first optical surface 11d is deteriorated in the reflow process after molding or the shape of the antireflection structure described later. , Changes in color and the like can be suppressed.

  As shown in an enlarged view in FIG. 2, an antireflection structure 51 and a protective layer 52 are provided on the first optical surface 11 d of the first lens element 11. In FIG. 2, the boundary between the first optical surface 11d and the antireflection structure 51 does not exist clearly, but is shown by a dotted line for convenience.

  The antireflection structure 51 has fine uneven shapes randomly arranged in a plane such as the first optical surface 11d. The antireflection structure 51 has a tapered structure in which the volume density of the concavo-convex shape increases from the incident light side toward the optical element center side. That is, the antireflection structure 51 is a collection of substantially cone-shaped fine protrusions. The roughness (Rz: 10-point average roughness) of the antireflection structure 51 is 10 nm or more and 1000 nm or less. The roughness Rz of the antireflection structure 51 is preferably 50 nm or more and 800 nm or less, and more preferably 250 nm or more and 800 nm or less. The antireflection structure 51 is formed by using an ion beam. Here, in general, the reflectance at a certain interface is determined by the difference in refractive index between the two spaces sandwiching the interface, and the surface reflectance increases as the difference increases. Since the antireflection structure 51 has a concavo-convex shape of the use wavelength level or less formed on the first optical surface 11d, there is a sudden change in refractive index between the antireflection structure 51 and the first optical surface 11d. There are no interfaces. Thereby, the refractive index change in the antireflection structure 51 becomes gradual, and the surface reflectance decreases. This effect does not depend on the wavelength or the incident angle. Therefore, the antireflection structure 51 can suppress wavelength dependency and angle dependency as compared with a conventional structure having a low refractive index layer or the like. The principle of antireflection by a conventional structure having a low refractive index layer or the like is based on light interference. When light is perpendicularly incident on a structure having a low refractive index layer or the like, the reflectance is reduced most at a wavelength four times the film thickness, and the apparent film thickness is substantial for light having an incident angle θ. Appears as the product of film thickness and cos θ. As a result, in the case of a structure having a low refractive index layer or the like, unlike the case of the present embodiment, wavelength dependency and incident angle dependency appear.

The protective layer 52 is coated on the entire surface of the first lens array layer 102, and is uniformly formed on the antireflection structure 51. The protective layer 52 is formed by using coating, vapor deposition, sputtering, ion beam sputtering, or the like. Note that vapor deposition, sputtering, and ion beam sputtering are preferably used because uniform and accurate film thickness control can be performed over a wide area. As a material of the protective layer 52, for example, SiO ₂ , Al ₂ O ₃ or the like is used. The thickness of the protective layer 52 is about 5 nm to 50 nm. By providing the protective layer 52, it is possible to impart dustproof, antifouling, wear resistance, electrostatic resistance, and the like to the antireflection structure 51, and thus the first optical surface 11d and the first flange surface 11g.

  Returning to FIG. 1B, the second lens array layer 103 is also made of resin and is formed on the other surface 101 c of the substrate 101. The second lens array layer 103 has a circular outer shape in a plan view, and two-dimensionally includes a plurality of second lens elements 12 each including the second lens body 12a and the second flange portion 12b in the XY plane. Are arranged at equal intervals. These second lens elements 12 are integrally molded via a flat connecting portion 12c. The combined surface of each second lens element 12 and the connecting portion 12c is a second molding surface 103a that is collectively molded by transfer. The second lens body 12a is, for example, an aspheric lens part, and has a concave second optical surface 12d as an optical function part. The surrounding second flange portion 12b has a flat second flange surface 12g extending around the second optical surface 12d, and the outer periphery of the second flange portion 12b is also a connecting portion 12c. The second flange surface 12g is disposed in parallel to the XY plane perpendicular to the optical axis OA. On the first optical surface 12 d of the second lens element 12, an antireflection structure 51 and a protective layer 52 shown in an enlarged manner in FIG. 2 are provided. Since the shape, material, and the like of the second lens array layer 103 are the same as those of the first lens array layer 102, description thereof is omitted.

  In the optical element array 100, a diaphragm may be provided between the substrate 101 and the first lens array layer 102 or between the substrate 101 and the second lens array layer 103. In this case, the aperture of the diaphragm is arranged in alignment with each of the first and second lens bodies 11a and 12a.

Method for Manufacturing Optical Element Array Hereinafter, an example of a lens manufacturing apparatus for manufacturing the optical element array 100 shown in FIG. 1A and the like will be described with reference to FIGS. 3 and 4. The lens manufacturing apparatus includes a molding device shown in FIG. 3 (only the molding die 40 is shown) and a processing device 60 shown in FIG.

  The molding apparatus is used for molding the optical element array 100 by pouring a fluid resin into the molding die 40 and solidifying it. Although illustration is omitted, in addition to the molding die 40 as a main member, the molding apparatus applies a mold lifting device for moving, opening and closing the molding die 40, and resin to the substrate 101. A resin coating device for solidifying the resin, a UV light generating device for solidifying the resin, a mold release device for taking out the molded optical element array 100, a control driving device for driving these devices, and the like.

  As shown in FIG. 3, the molding die 40 includes a first die 41, a second die 42, and a spacer 43. The first lens array layer 102 and the second lens array layer 103 are sequentially formed on both surfaces 101b and 101c of the substrate 101, and the first mold 41 is located on the one surface 101b side that becomes the upper side of the substrate 101 when releasing. The second mold 42 is placed in close contact with the second lens array layer 103 on the other surface 101 c side, which is the lower side of the substrate 101.

  The first mold 41 is for molding the first molding surface 102 a of the optical element array 100. The first mold 41 is made of light transmissive glass and has a thick disk-shaped outer shape. The first mold 41 has a first transfer surface 41 b corresponding to the first molding surface 102 a of the first lens array layer 102 on the end surface 41 a on the substrate 101 side. That is, a plurality of first transfer surfaces 41b are formed on the end surface 41a. The first transfer surface 41b includes a first optical surface transfer surface 41c for forming the first optical surface 11d of the first molding surface 102a and a first flange surface transfer surface 41d for forming the first flange surface 11g. Including. The first optical surface transfer surface 41c is concave corresponding to the shape of the first optical surface 11d, and the first flange surface transfer surface 41d is flat corresponding to the shape of the first flange surface 11g. ing.

  The second mold 42 is for molding the second molding surface 103 a of the optical element array 100. Similarly to the first mold 41, the second mold 42 is also made of light-transmitting glass and has a thick disk-shaped outer shape. The second mold 42 has a second transfer surface 42 b corresponding to the second molding surface 103 a of the second lens array layer 103 on the end surface 42 a on the substrate 101 side. The second transfer surface 42b includes a second optical surface transfer surface 42c for forming the second optical surface 12d of the second molding surface 103a and a second flange surface transfer surface 42d for forming the second flange surface 12g. Including. The second optical surface transfer surface 42c is convex corresponding to the shape of the second optical surface 12d, and the second flange surface transfer surface 42d is flat corresponding to the shape of the second flange surface 12g. It has become.

  The spacer 43 forms the side surface 100 a of the optical element array 100 and defines the thickness of the first and second lens array layers 102 and 103. The spacer 43 is sandwiched between the first mold 41 and the second mold 42 and has an annular outer shape.

  As shown in FIG. 4, the processing device 60 includes a vacuum chamber 61, a stage 62, an ion gun 63, a neutralization gun 64, a vapor deposition device 65, gas supply units 66 and 67, a gas discharge unit 68, And a control unit 69.

  The vacuum chamber 61 is for keeping the inside of the processing apparatus 60 airtight. In the vacuum chamber 61, a stage 62, an ion gun 63, a neutralizing gun 64, and a vapor deposition device 65 are provided. The vacuum chamber 61 communicates with the gas supply units 66 and 67 through the port 61a, and communicates with the gas discharge unit 68 through the port 61b.

  The stage 62 is provided in the upper part of the vacuum chamber 61 and can move in the X direction, the Y direction, and the Z direction. The optical element array 100 is placed and fixed on the stage surface 62a of the stage 62 facing the ion gun 63 and the like. By adjusting the position of the stage 62, the position of the optical element array 100 is adjusted.

  The ion gun 63 is for forming the antireflection structure 51 on the first and second optical surfaces 11 d and 12 d of the optical element array 100. The ion gun 63 extracts ions in the plasma by applying a voltage or the like and discharges the ions outside the ion gun 63. Specifically, the ion gun 63 ionizes the supplied gas and applies a beam voltage between the anode 63 a and the cathode 63 b of the ion gun 63. The ion gun 63 allows ionized gas (for example, positive ions) to approach and pass the cathode 63b side, and discharges it into the vacuum chamber 61 as an ion beam. The emitted ion beam is applied to the first and second optical surfaces 11 d and 12 d of the optical element array 100 on the stage 62. As a result, the exposed resin portions where the mask pattern MA described later is not formed on the first and second optical surfaces 11d and 12d are etched.

  The neutralizing gun 64 is for neutralizing ions in the ion beam to suppress the influence of electrolytic distribution. An ionizing gas is introduced into the neutralizing gun 64 from a gas introduction source (not shown), and the introduced gas is ionized. When electrons generated by ionization are discharged to the vacuum chamber 61, the gas ionized by the ion gun 63 is neutralized by the electrons. A neutralization grid may be used instead of the neutralization gun 64.

The vapor deposition device 65 is for forming a mask pattern MA, which will be described later, on the optical element array 100 or for forming the protective layer 52. The vapor deposition apparatus 65 performs vacuum vapor deposition of, for example, SiO ₂ , Al ₂ O ₃ , MgF ₂ , ZrO ₂ , TiO ₂ , CeO ₂ or the like. Thereby, an island-like pattern that becomes the mask pattern MA and a thin film that becomes the protective layer 52 can be formed on the first and second optical surfaces 11 d and 12 d of the optical element array 100. Note that if a sputtering device or an ion beam sputtering device is provided instead of the vapor deposition device 65, sputtering, ion beam sputtering, or the like can be performed.

The gas supply units 66 and 67 supply an introduction gas for irradiating an ion beam. As the introduction gas, an inert gas and a reactive gas are used. Examples of the inert gas include argon (Ar), nitrogen (N ₂ ), helium (He), krypton (Kr), neon (Ne), and a mixed gas thereof. An example of the reactive gas is oxygen (O ₂ ). Here, Ar, O ₂ , N ₂ , and a mixed gas thereof are preferable because they are relatively inexpensive. Among these, O ₂ and a mixed gas containing the same are particularly preferable because reactive etching can be performed simultaneously with the etching of the first and second optical surfaces 11d and 12d.

  The gas discharge unit 68 is for adjusting the degree of vacuum in the vacuum chamber 61. The inside of the vacuum chamber 61 is exhausted to a predetermined degree of vacuum by the gas discharge unit 68.

  The control unit 69 is for controlling operations of the stage 62, the ion gun 63, the neutralization gun 64, the vapor deposition device 65, and the gas discharge unit 68.

  The ion beam generated by the processing apparatus 60 is generated by giving high kinetic energy to ions in plasma. Although the emitted ions have a charge, they are not affected by the electric field because the mass of the ions is large, and are emitted with high straightness. As a result, irradiation with a uniform energy and density ion distribution onto the object is realized, and therefore it is effective when used for etching the above-described relatively large optical element array 100. On the other hand, plasma tends to be preferentially etched from the protrusions of the object due to the influence of electric field distribution and plasma density. Therefore, a uniform etching rate cannot be maintained with respect to the first and second optical surfaces 11d and 12d having protrusions and corners, and the first and second optical surfaces 11d and 12d have different shapes depending on the shape of the first and second optical surfaces 11d and 12d. The antireflection effect of the antireflection structure 51 produced on the two optical surfaces 11d and 12d may be biased. The protruding portion and the corner portion are, for example, a diffractive structure, a boundary between the second optical surface 12d and the second flange surface 12g, and a spacer portion when the spacer is integrally formed.

  Hereinafter, the manufacturing process of the optical element array 100 shown in FIG. 1 (A) and the like will be described with reference to FIGS. 5 (A) to 5 (D) and FIG. The manufacturing process of the wafer lens 100 roughly includes a molding process in which a resin is applied to the substrate 101 and molding, a patterning process in which a mask pattern is formed in the molded optical element array 100, and a first of the optical element array 100. And an etching process for forming the antireflection structure 51 on the second optical surfaces 11d and 12d, and a coating process for providing the protective layer 52 on the antireflection structure 51.

[Molding process]
The molding step is performed by operating a mold lifting device, a resin coating device, and a UV light generator (not shown) while using the first and second molds 41 and 42 shown in FIG.

  First, the first lens array layer 102 is formed on one surface 101b of the substrate 101 (step S11). Specifically, as shown in FIG. 5A, the side surface 101 a of the substrate 101 is fixed in advance with a spacer 43. Here, the substrate 101 is placed on the stage SS, and the other surface 101c serving as a lower surface is brought into close contact with the upper surface of the stage SS, so that the warpage of the substrate 101 is prevented. The resin coating apparatus is operated to apply the resin onto one surface 101b which is the upper surface of the substrate 101 fixed on the stage SS. The mold lifting / lowering device is operated, and the first mold 41 is lowered toward the substrate 101 coated with resin in a state where the first mold 41 is aligned with the stage SS or the like. Between the substrate 101 and the first mold 41, the end surface 43 a of the spacer 43 is in contact with the substrate 101 and the end surface 43 b perpendicular to the end surface 43 a of the spacer 43 is in contact with the outer edge portion 41 e of the first mold 41. Resin thickness, that is, the thickness of the connecting portion 11c (first flange portion 11b) of the first lens array layer 102 is defined. The UV light generator is operated to irradiate UV light from the upper side of the first mold 41, and the resin sandwiched between the one surface 101b of the substrate 101 and the end surface 41a of the first mold 41 is solidified.

  Next, the second lens array layer 103 is formed on the other surface 101 c of the substrate 101. As shown in FIG. 5B, the mold lifting device is operated to invert the substrate 101 and the first mold 41 in a state of being integrated with each other through the first lens array layer 102, and Are fixed so that the surface 101c is on the upper side. The resin coating apparatus is operated to apply the resin onto the other surface 101c of the fixed substrate 101. The mold lifting device is operated, and the second mold 42 is lowered toward the substrate 101 coated with the resin in a state where the second mold 42 is aligned with the first mold 41 and the like. Between the substrate 101 and the second mold 42, the end surface 43 a of the spacer 43 is in contact with the substrate 101 and the end surface 43 c perpendicular to the end surface 43 a of the spacer 43 is in contact with the outer edge portion 42 e of the second mold 42. Resin thickness, that is, the thickness of the connecting portion 12c (second flange portion 12b) of the second lens array layer 103 is defined. The UV light generator is operated to irradiate UV light from the upper side of the second mold 42, and the resin sandwiched between the other surface 101 c of the substrate 101 and the end surface 42 a of the second mold 42 is solidified.

  After the resin forming the first and second lens array layers 102 and 103 is solidified, the spacer 43 is removed from the substrate 101 and the first and second molds 41 and 42 as shown in FIG.

  Finally, as shown in FIG. 5D, the optical element array 100 is released from the first and second molds 41 and 42 (step S12).

[Patterning process]
Hereinafter, with reference to FIGS. 6 and 7A to 7C, a patterning process and etching for forming the antireflection structure 51 on the first and second optical surfaces 11d and 12d of the optical element array 100 are performed. The process will be described. Since the processing steps for the first and second optical surfaces 11d and 12d are the same, only the case where the antireflection structure 51 is formed on the first optical surface 11d will be described for convenience.

  The patterning process is performed as a pre-process for irradiating the optical element array 100 with an ion beam, and forms a mask pattern MA on the first optical surface 11d (step S13). The mask pattern MA is a fine island pattern as shown in an enlarged view in FIG. The mask pattern MA has a plurality of islands IM arranged at random. The patterning step is performed using a technique such as photoresist application, film deposition, or etching. For example, when a film deposition method is used, an initial process of thin film growth is used. In the initial growth process of the thin film, a state where the growth nucleus of the film grows as an island IM, that is, island growth occurs. In the state of island growth before the film is layered, there are a portion where the island IM exists and a portion where the first optical surface 11d is exposed, so that it functions as a mask pattern.

When the film deposition method is used, the patterning process is performed in the processing apparatus 60. The number density and size of the islands IM of the mask pattern MA can be changed as appropriate by adjusting the film growth conditions. For example, the height of the deposited island IM is preferably 0.1 nm to 30 nm, and more preferably 1 nm to 10 nm. Examples of the mask material include a low refractive transparent material and a high refractive transparent material. Specifically, there are SiO ₂ , Al ₂ O ₃ , and MgF ₂ as the low refractive transparent material. In addition, examples of highly refractive transparent materials include ZrO ₂ and TiO ₂ . In particular, in the case of a low refractive transparent material, even if it remains on the antireflection structure 51, it is difficult to cause reflection. By patterning the mask pattern MA, the etching rate varies depending on the position on the surface of the first optical surface 11d, and a fine uneven shape can be formed in the etching process described later.

  When the mask pattern MA is formed by film deposition and etching, as shown in FIG. 4, for example, a vapor deposition device 65 is disposed in the processing device 60 so that the patterning step can be performed before the etching step. Thereby, the evacuation time for an etching process can be omitted.

[Etching process]
An etching process is performed by using the processing apparatus 60 shown in FIG.

  First, the optical element array 100 is arranged on the stage 62 so that an ion beam emitted from the ion gun 63 of the processing apparatus 60 is irradiated onto a target surface of the optical element array 100, that is, the first optical surface 11d.

Next, the gas in the vacuum chamber 61 is exhausted by the gas exhaust unit 68. The exhaust pressure maintained by the exhaust is 1 × 10 ⁻¹ Pa or less. The exhaust pressure is more preferably 1 × 10 ⁻³ Pa or less. The exhaust pressure needs to be 1/10 or less of the introduced gas described later.

Next, an introduction gas is introduced into the vacuum chamber 61. As the introduction gas, for example, Ar, O ₂ , N ₂ , He, Kr, Ne, or a mixed gas thereof is used. Here, when an inert gas and a reactive gas are used as the introduced gas, the etching rate can be easily adjusted. The pressure of the introduced gas is 1 Pa or less. The pressure of the introduced gas is more preferably 1 × 10 ⁻² Pa or less. Etching at a lower gas pressure lengthens the mean free path of ions. Therefore, the kinetic energy of ions is not easily lost before colliding with the first optical surface 11d, and the etching rate is increased. Therefore, the etching rate can be increased by setting the total pressure so that the mean free path of ions is the same as the distance between the optical element array 100 and the ion gun 63 or about 1/10. In the etching process, the difference between the maximum etching rate and the minimum etching rate in the portion where the first optical surface 11d is disposed is within 10% of the maximum etching rate.

  An ion beam is emitted in the state of the vacuum chamber 61 described above, and ion irradiation is performed on the first optical surface 11d. At this time, the acceleration energy of ions is 1 W to 100 kW. The acceleration energy of ions is preferably 10 W to 10 kW, and more preferably 50 W to 1 kW.

  By irradiation with the ion beam, as shown in FIG. 7B, the portion of the optical element array 100 where the resin is exposed is etched together with the island IM of the mask pattern MA. As a result, the antireflection structure 51 having a structure in which the concave-convex volume density increases from the incident light side toward the optical element center side is formed (step S14).

  If the island IM of the mask pattern MA is not completely removed after the etching process, the mask pattern MA may be removed by adjusting the ion beam as shown in FIG. 7C.

[Coating process]
Hereinafter, the coating process for forming the protective layer 52 will be described with reference to FIGS. 6 and 7D.

  As shown in FIG. 7D, in the coating process, the protective layer 52 is coated on the antireflection structure 51 (step S15). As a coating method, vapor deposition, sputtering, ion beam sputtering ring, coating, or the like is used. Of these coating methods, vapor deposition, sputtering, and ion beam sputtering are preferable because uniform and accurate film thickness control can be performed over a wide area. Here, usually, vapor deposition, sputtering, and ion beam sputtering require time for evacuation. As shown in FIG. 4, the coating process can be continuously performed after the etching process is performed by disposing, for example, a vapor deposition apparatus 65 in the processing apparatus 60. Thereby, the evacuation time for a coating process can be omitted.

  According to the optical element array manufacturing method and the optical element array 100 described above, it is possible to manufacture the optical element array 100 in which the antireflection structure 51 having a fine uneven shape is in a stable state. Specifically, since the antireflection structure 51 is formed of the same material as the first and second optical surfaces 11d and 12d, which are optical function units, the antireflection structure 51 and the first and second optical surfaces 11d, The optical element array 100 in which the difference in linear expansion coefficient from 12d is small and cracks are not generated can be produced. Further, since the antireflection structure 51 is formed of the same material as the first and second optical surfaces 11d and 12d, an interface exists between the antireflection structure 51 and the first and second optical surfaces 11d and 12d. do not do. Therefore, it is possible to manufacture the optical element array 100 in which peeling does not occur in the antireflection structure 51 portion. In addition, since the ion beam whose energy state is controlled is emitted from the ion irradiation port and uniformly irradiated on the entire surface of the optical element array 100, the antireflection structure 51 on the optical element array 100 should be uniform. Can do.

Lens unit below with reference to FIG. 1 (C) or the like, will be described lens unit 200 separated from the optical element array 100.

  The lens unit 200 is used as an imaging lens, for example. The lens unit 200 includes a first compound lens 10 and a second compound lens 110. The lens unit 200 is obtained by laminating and joining two optical element arrays 100 and then cutting them out by dicing. Here, the dotted lines in FIG. 1A showing the optical element array 100 before cutting out indicate the outer edges of a large number of compound lenses 10 arranged at the lattice points. The outside of the compound lens 10 across the boundary line of each compound lens 10 is the connecting portions 11c and 12c. In addition, since the structure of the 1st and 2nd compound lenses 10 and 110 is substantially the same, the 1st compound lens 10 is mainly described on account of description.

  As shown in FIG. 1C, the compound lens 10 is a quadrangular prism-like member, and has a quadrangular outline when viewed from the optical axis OA direction. The compound lens 10 includes the first lens element 11, the second lens element 12, and the flat plate portion 13 sandwiched therebetween. The flat plate portion 13 is a portion obtained by cutting out the substrate 101. The compound lens 10 is housed in, for example, a separately prepared holder, and is bonded to the imaging circuit board as an imaging lens. In the first lens element 11, the first lens body 11 a is provided in the central portion around the optical axis OA of the compound lens 10 and has a circular outline. The first flange portion 11b extends around the first lens body 11a and has a rectangular outline. Also in the second lens element 12, the second lens body 12 a is provided in the central portion around the optical axis OA of the compound lens 10 and has a circular outline. The second flange portion 12b extends around the second lens body 12a and has a square contour.

  Similarly, the second compound lens 110 includes a first lens element 111, a second lens element 112, and a flat plate portion 113.

  According to the lens unit 200 described above, since the antireflection structure 51 is made of the same material as the first and second optical surfaces 11d and 12d, it is possible to prevent the occurrence of defects such as film peeling and cracks. . Further, by using the optical element array 100 having the uniform antireflection structure 51, the lens unit 200 having high-precision optical characteristics is obtained.

Camera module below with reference to FIG. 8, will be described camera module 70 assembled with the lens unit 200.

  The camera module 70 is a small camera part that combines an image sensor and a lens, and can capture an image to be captured. As shown in FIG. 8, the camera module 70 includes a main body module 71 and a lens module 72. In the imaging device 300, the camera module 70 is incorporated on a circuit board BB on which electronic components constituting an electronic circuit of a mobile information terminal device such as a mobile phone are mounted. Specifically, the entire camera module 70 is mounted on the circuit board BB by mounting the main body module 71 on the circuit board BB.

  The main body module 71 is a light receiving module in which an image sensor 73 that is an image sensor such as a CCD or CMOS is mounted in advance on the sub-substrate SB. The upper part of the image sensor 73 is sealed with a sealing part 74. On the upper surface of the image sensor 73, a light receiving portion 73a in which a number of pixels that perform photoelectric conversion are arranged in a grid is formed. By forming an optical image on the light receiving unit 73a by the lens module 72, an image signal obtained by photoelectric conversion in each pixel is output. The sub board SB is mounted on the circuit board BB with lead-free solder 75. Thereby, the camera module 70 including the sub board SB is fixed to the circuit board BB. At this time, the connection electrode (not shown) of the sub board SB and the circuit electrode (not shown) on the upper surface of the circuit board BB are electrically connected.

  The lens module 72 includes an outer frame 77 that is a cylindrical holder that supports the lens unit 200 as an imaging lens. A lens unit 200 is held on the upper portion of the outer frame 77. A lower portion of the outer frame 77 is a mounting portion 77b that is inserted into a mounting hole IS provided in the sub-substrate SB and fixes the lens module 72 to the sub-substrate SB. For this fixing, a method of pressing and fixing the mounting portion 77b into the mounting hole IS, a method of bonding with an adhesive, or the like is used.

  As described above, the lens unit 200 includes the first and second compound lenses 10 and 110 (see FIG. 1C), and forms an image of reflected light from the subject on the light receiving unit 73a of the image sensor 73. .

  A diaphragm member may be provided on the lens unit 200.

Camera module manufacturing method below with reference to FIG. 9, a method for manufacturing the camera module 70.

  First, the lens unit 200 is manufactured. In manufacturing the lens unit 200, the optical element array 100 is stacked and temporarily fixed (step S21). At this time, a part of the optical element array 100 is marked, and, for example, two optical element arrays 100 are aligned and stacked. The optical element array 100 is designed so that optical characteristics appear when stacked. Therefore, there is no need for optical adjustment, and the cost can be reduced.

  Next, the stacked optical element array 100 is cut (step S22). This cutting process includes a laser and a rotary saw.

  The image sensor 73 and the outer frame 77 are attached to the lens unit 200 manufactured in this way, and are joined (step S23). The lens unit 200 is incorporated at an appropriate position in the outer frame 77 so as to form an image on the light receiving portion 73a of the image sensor 73.

  Next, the mounting portion 77b of the outer frame 77 is inserted and fixed in the mounting hole IS of the sub-substrate SB to form the camera module 70. Thereafter, the camera module 70 and other electronic components are placed at a predetermined mounting position of the circuit board BB to which the solder 75 has been applied (potted) in advance.

  Thereafter, the circuit board BB on which the camera module 70 and other electronic components are mounted is transferred to a reflow furnace (not shown) by a belt conveyor or the like, and the circuit board BB is subjected to a reflow process and heated at a temperature of about 260 ° C. (Step S24). As a result, the solder 75 is melted, the camera module 70 is mounted on the circuit board BB together with other electronic components, and the imaging device 300 is formed.

  Note that if the optical element array 100 is formed of a heat-resistant resin, the camera module 70 can be further improved in heat resistance.

  According to the camera module manufacturing method and the camera module 70 described above, since the antireflection structure 51 is formed of the same material as the first and second optical surfaces 11d and 12d, film peeling or cracking occurs even after the reflow process. Thus, the optical element array 100 having the uniform antireflection structure 51 can be used. Thereby, it is possible to provide the camera module 70 having high-precision optical performance such as obtaining a clear image. In particular, since the first and second optical surfaces 11d and 12d have the anti-reflection structure 51 having a substantially cone-shaped fine unevenness, the angle dependence is small, and the difference in luminous intensity is small between the periphery and the center of the image. The camera module 70 is obtained. Further, by passing through the reflow process, the camera module 70 is more firmly bonded.

Hereinafter, the etching rate by the ion beam will be described.
Table 1 shows the relationship between the material to be etched and the etching rate.

Etching was performed by irradiating the resin and the glass with an ion beam using a mixed gas of 66.6% Ar and 33.3% O ₂ . As the resin, a resin material (zeonex: registered trademark, manufactured by ZEON Corporation) and an acrylic resin were used. Moreover, BK7 was used for glass. The resin and glass are partially masked with a cover glass in advance. The etching rate was calculated by measuring the step.

  Here, when the etching rate of the object to be processed is low, the mask pattern MA may disappear before the antireflection structure 51 is formed. As shown in Table 1, the resin etching rate is higher than the glass etching rate. Therefore, it can be seen that a resin is preferable as the material of the first and second lens array layers 102 and 103 of the optical element array 100.

[Second Embodiment]
Hereinafter, a camera module and the like according to the second embodiment will be described. Note that the camera module and the like of the second embodiment is a modification of the camera module and the like of the first embodiment, and parts not specifically described are the same as those of the first embodiment.

  As shown in FIG. 10A, the camera module 270 includes an image sensor chip 271, a lens unit 200, and an IR cut filter 278.

  The lens unit 200 includes a lens support 277 extending from the first flange portion 11 b of the second compound lens 110. The lens support 277 has a rectangular outer shape and projects from the first lens body 11a of the second compound lens 110 in a direction parallel to the optical axis OA. The bottom surface of the lens support 277 is attached to the corresponding position of the image sensor chip 271 via the IR cut filter 278. A light shielding layer may be formed on the side surface of the IR cut filter 278.

  The image sensor chip 271 includes a silicon chip 273 and a support glass substrate 274. A CCD, CMOS, or the like is formed on the surface of the silicon chip 273. Electrode pads 273a and 273b are formed on the periphery of the surface of the silicon chip 273. These electrode pads 273a and 273b are connected to an input / output circuit of the image sensor chip 271. Rewirings 273c and 273d that penetrate the silicon chip 273 and reach the back surface of the image sensor chip 271 are connected to the lower surfaces of the electrode pads 273a and 273b. The rewirings 273c and 273d are exposed on the periphery of the back surface of the silicon chip 273. Bump electrodes 273e and 273f are formed on the rewirings 273c and 273d on the back surface of the silicon chip 273.

  The support glass substrate 274 is for supporting the silicon chip 273 and is provided on a CCD, a CMOS, or the like.

  The IR cut filter 278 is a member that reflects infrared light out of incident light from the lens unit 200 and transmits visible light.

  A diaphragm member may be provided on the lens unit 200.

  Hereinafter, a method for manufacturing the camera module 270 will be described with reference to FIGS. The camera module 270 of the second embodiment is manufactured separately from a combination of the optical element array 100 and an image sensor array 400 (described later) in which a plurality of CCDs, CMOSs, and the like, which are image sensors, are formed.

  First, two optical element arrays 100, an IR cut filter wafer 500, and an image sensor array 400 are produced. Here, the IR cut filter wafer 500 is a flat member. The image sensor array 400 includes a plurality of image sensor chips 271 corresponding to the positions of the lens units 200 of the stacked optical element array 100.

  Next, the manufactured optical element array 100, the IR cut filter wafer 500, and the imaging element array 400 are stacked, and the structure CS is manufactured (step S31). The structure CS is fixed by an adhesive.

  After bonding the optical element array 100, the IR cut filter wafer 500, and the image sensor array 400, the structure CS is cut with a laser, a rotary saw, or the like along the boundary between two adjacent image sensor chips 271 (step) S32). Thereby, the camera module 270 is produced.

  Thereafter, the camera module 270 is mounted on a circuit board (not shown) via bump electrodes 273e and 273f on the back surface of the image sensor chip 271. Specifically, the camera module 70 and other electronic components are placed at a predetermined mounting position on a circuit board to which solder has been applied (potted) in advance. The circuit board on which the camera module 270 and other electronic components are mounted is transferred to a reflow furnace (not shown) by a belt conveyor or the like, and the circuit board is subjected to a reflow process and heated at a temperature of about 260 ° C. (step S33). . As a result, the solder is melted, and the camera module 270 is mounted on the circuit board together with other electronic components to form an imaging device.

  According to the camera module manufacturing method and the camera module 270 described above, since the antireflection structure 51 is formed of the same material as the first and second optical surfaces 11d and 12d, film peeling or cracking occurs even after the reflow process. Thus, the optical element array 100 having the uniform antireflection structure 51 can be used. Thereby, it is possible to provide the camera module 70 having high-precision optical performance such as obtaining a clear image. Further, the image sensor chip 271 and the lens unit 200 provided with an image sensor such as a CCD or CMOS are stacked in the state of a wafer after being stacked with the image sensor chip 271 and the lens unit 200. Since the process of combining with can be shortened, the cost can be reduced.

[Third Embodiment]
The optical element array according to the third embodiment will be described below. The optical element array of the third embodiment is a modification of the optical element array of the first embodiment, and parts not specifically described are the same as those of the first embodiment.

  As shown in FIG. 12, the substrate 101 is not provided in the optical element array 310 of the third embodiment. In other words, the optical element array 310 includes the first lens array layer 102 and the second lens array layer 103. As described above, when the molded first and second lens array layers 102 and 103 themselves are stable in shape and can be molded easily, the substrate 101 may not be used. In FIG. 12, for convenience, the boundary between the first lens array layer 102 and the second lens array layer 103 is indicated by a dotted line, but the first and second lens array layers 102 and 103 are formed integrally. Can do.

  Although the optical element array manufacturing method and the like according to the present embodiment have been described above, the optical element array manufacturing method and the like according to the present invention are not limited to the above. For example, in the above embodiment, the shapes and sizes of the first and second optical surfaces 11d and 12d can be changed as appropriate according to the application and function.

  In the above-described embodiment, the optical element array 100 is used for various purposes such as a mirror, a diffractive structure, an illumination component, and an optical transmission component in addition to the lens.

  Moreover, in the said embodiment, the optical element array 100 does not need to be disk shape, and can have various outlines, such as an ellipse. For example, the dicing process can be simplified by forming the optical element array 100 into a square plate shape from the beginning.

  In the above-described embodiment, the number of the first and second lens elements 11 and 12 formed in the optical element array 100 is not limited to four as illustrated, and may be two or more. At this time, the arrangement of the first and second lens elements 11 and 12 is preferably on a lattice point for convenience of dicing. Furthermore, the interval between the adjacent first and second lens elements 11 and 12 is not limited to the illustrated one, and can be set as appropriate in consideration of workability and the like.

  In the above embodiment, the shape of the substrate 101 is not limited to a circle, and may be, for example, an ellipse, a polygon, or a roll. Further, the first and second lens array layers 102 and 103 may cover a part of the surface, not the entire surface 101 b or 101 c of the substrate 101. Alternatively, the first and second lens array layers 102 and 103 may not be provided on both sides of the substrate 101, but the first or second lens array layers 102 and 103 may be provided only on one side.

  In the above embodiment, the first and second lens elements 11 and 12 may be randomly arranged in the optical element array 100. Further, in one optical element array 100, the first and second lens elements 11, 12 having different shapes and sizes may be arranged.

  In the above embodiment, the resin is applied to the one surface 101b and the other surface 101c of the substrate 101, but the resin is applied to the first and second transfer surfaces 41b and 42b of the first and second molds 41 and 42. It may be applied.

  Moreover, in the said embodiment, you may apply | coat a coupling agent to the one surface 101b and the other surface 101c of the board | substrate 101 previously. In addition, a release agent may be applied in advance to the first and second transfer surfaces 41 b and 42 b of the first and second molds 41 and 42.

  In the above-described embodiment, various methods can be used as the method for forming the optical element array 100 other than a method using a mold in which a resin is poured into the molding die 40 and solidified. For example, the optical element array 100 may be manufactured using thermal fusion, heat treatment, vapor deposition, injection molding, coating, etching after deposition, or the like. In consideration of the shape accuracy and molding time of the first and second optical surfaces 11d and 12d, a method using injection molding or a mold is preferable.

  Moreover, in the said embodiment, although the two gas supply parts 66 and 67 are provided, 1 or 3 or more may be sufficient.

  In the above embodiment, the island IM of the mask pattern MA may not be randomly arranged.

  In the above embodiment, the lens unit 200 is attached using solder, fusion, assembly, butt, or the like in addition to the adhesive. The lens unit 200 separated from the optical element array 100 does not peel off or crack in the heating process such as soldering. Therefore, if soldering is used to attach the lens unit 200, a stronger and simpler bonding process can be performed.

  In the above embodiment, when only one compound lens 10 is incorporated in the camera modules 70 and 270, the optical element array 100 need not be stacked.

  In the above embodiment, in the manufacturing process of the optical element array 100, the first and second lens array layers 102 and 103 are first molded and then released. The second lens array layer 103 may be molded and released after the release. In addition, each step may be performed continuously on the first and second lens array layers 102 and 103, or each step may be performed on the first lens array layer 102 and then the second lens array layer 103 may be formed. On the other hand, you may perform each process.

  Moreover, in 2nd Embodiment, the order of each process of lamination | stacking of the optical element array 100 grade | etc., Cutting | disconnection, and joining can be changed freely. For example, after the optical element array 100 is cut, the optical element array 100 may be attached to a sheet or the like, temporarily fixed together with the separated optical element array 100, and then laminated and bonded. In this case, since the optical element array 100 is cut in advance, the structure CS can be cut easily with high accuracy.

DESCRIPTION OF SYMBOLS 10,110 ... Compound lens 11, 12, 111, 112 ... Lens element, 11a, 12a ... Lens main body, 11b, 12b ... Flange part, 11c, 12c Connection part, 11d, 12d ... Optical surface, 11g, 12g ... Flange Surface, 40 ... Mold, 41, 42 ... Mold, 51 ... Antireflection structure, 52 ... Protective layer, 60 ... Processing device, 61 ... Vacuum chamber, 62 ... Stage, 63 ... Ion gun, 64 ... Neutralization gun 65 ... Vapor deposition apparatus, 66, 67 ... Gas supply unit, 68 ... Gas discharge unit, 69 ... Control unit, 70, 270 ... Camera module, 71 ... Main unit module, 72 ... Lens module, 73 ... Image sensor, 100, 310 ... Optical element array, 101 ... Substrate, 102, 103 ... Lens array layer, 200 ... Lens unit, 271 ... Image sensor chip, 273 ... Silicon chip, 278 ... IR cut filter, 300 ... Imaging device, 400 ... Image sensor array, 500 ... Cut filter wafer, AX ... Axis, BB ... Circuit board, CS ... Structure, IM ... Island, MA ... Mask pattern, OA ... Optical axis, SS ... Stage

Claims (14)

A method of manufacturing an optical element array in which a plurality of resin optical elements having an optical function part are formed,
A patterning step of forming a mask pattern on the optical function part of the molded optical element array;
An etching step of providing an antireflection structure by etching with an ion beam in the optical function unit;
An optical element array manufacturing method comprising:   In the etching step, a difference between a maximum etching rate and a minimum etching rate in a portion where the optical element of the optical element array is disposed is within 10% of the maximum etching rate. Item 2. A method for manufacturing an optical element array according to Item 1.   The method of manufacturing an optical element array according to claim 1, wherein the mask pattern of the optical function unit is formed in a fine island shape.   The method for manufacturing an optical element array according to any one of claims 1 to 3, wherein an inert gas and a reactive gas are used in the etching step.   5. The optical element array according to claim 1, further comprising a coating step of providing a protective layer for protecting the antireflection structure on the antireflection structure after the etching step. 6. Manufacturing method. An optical element array in which a plurality of resin optical elements having an optical function part are formed,
An optical element array comprising: a fine concavo-convex antireflection structure formed by using an ion beam in the optical function unit.   The optical element array according to claim 6, wherein a depth of the uneven shape of the antireflection structure is not less than 50 nm and not more than 1000 nm.   The optical element array according to claim 6, wherein the resin has a heat resistance of 200 ° C. or higher.   The optical element array according to claim 6, wherein the antireflection structure has a protective layer on a surface thereof.   The optical element array according to any one of claims 6 to 9, wherein the optical element is for guiding light to an image pickup device itself having a plurality of photoelectric conversion elements.   A lens unit comprising an optical element separated from the optical element array according to any one of claims 6 to 10.   11. A camera module manufactured by combining an optical element separated from the optical element array according to claim 6 and an imaging element.   11. A camera module that is taken out from a combination of the optical element array according to any one of claims 6 to 10 and an image sensor array in which a plurality of image sensors are formed.   A camera module manufactured through a reflow process in a state in which an optical element separated from the optical element array according to any one of claims 6 to 10 and an imaging element are combined.

Images