KR102800184B1 - Liquid Lens, Camera Module, And Optical Device - Google Patents

Abstract

A liquid lens according to one embodiment of the present invention comprises a first plate including an inclined surface therein, a conductive liquid and a non-conductive liquid arranged on the inclined surface, a first electrode arranged on the inclined surface, a second electrode arranged on an upper portion of the first plate, and a black insulating layer arranged on an upper portion of the first electrode, wherein an interface formed by the conductive liquid and the non-conductive liquid can move along the black insulating layer arranged on the inclined surface.

Description

Liquid Lens, Camera Module, And Optical Device

The present invention relates to a lens having a variable focal length/distance. More specifically, the present invention relates to a liquid lens, a camera module, and an optical device capable of adjusting the focal length using electrical energy.

Users of portable devices want optical devices that have high resolution, are small in size, and have various shooting functions (optical zoom function (zoom-in/zoom-out), auto-focusing (AF) function, optical image stabilization (OIS) function, etc.). These shooting functions can be implemented by combining multiple lenses and directly moving the lenses, but increasing the number of lenses can increase the size of the optical device.

Autofocus and image stabilization functions are performed by moving or tilting multiple lens modules fixed to a lens holder and having their optical axes aligned in the optical axis or in the direction perpendicular to the optical axis, and a separate lens driving device is used to drive the lens modules. However, the lens driving device consumes a lot of power, and to protect it, a cover glass must be added separately from the camera module, which increases the overall thickness.

Therefore, research is being conducted on a liquid lens that performs autofocus and image stabilization functions by electrically controlling the curvature of the interface between two liquids.

The present invention provides a liquid lens, a camera module, and an optical device capable of preventing ghost or flare phenomena that deteriorate lens characteristics.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

According to one embodiment of the present invention, a liquid lens comprises: a first plate including an inclined surface therein; a conductive liquid and a non-conductive liquid arranged on the inclined surface; a first electrode arranged on the inclined surface; a second electrode arranged on an upper portion of the first plate; and a black insulating layer arranged on an upper portion of the first electrode; wherein an interface formed by the conductive liquid and the non-conductive liquid can move along the black insulating layer arranged on the inclined surface.

In some embodiments, the black insulating layer may be positioned so as not to overlap with the opening below the non-conductive liquid.

According to an embodiment, the black insulating layer may be placed in contact with the first electrode or the second electrode that transmits an electrical signal for controlling the interface.

According to an embodiment, the device may further include a transparent insulating layer disposed between the third plate and the non-conductive liquid.

According to an embodiment, the thicknesses of the transparent insulating layer and the black insulating layer may be the same.

According to an embodiment, the black insulating layer may be arranged to extend along the lower or upper portion of the first plate.

According to an embodiment, the black insulating layer may include a graphite coating, a soma film, or a black resin.

According to another embodiment of the present invention, a liquid lens comprises: a first plate including an opening area having a preset inclined surface; a conductive liquid and a non-conductive liquid arranged on the inclined surface; a first electrode arranged on the inclined surface; a second electrode arranged on an upper portion of the first plate; a third plate arranged below the first electrode; a second plate arranged on an upper portion of the second electrode; an insulating layer arranged on an upper portion of the first electrode; and an anti-reflection layer arranged on an upper portion of the insulating layer, wherein the anti-reflection layer is arranged at a position where an interface between the conductive liquid and the non-conductive liquid is formed along the inclined surface, thereby preventing reflection by the inclined surface.

A camera module according to one embodiment of the present invention may include: the liquid lens; an image sensor that converts light transmitted through the liquid lens into an electric signal; and a control circuit that generates an electric signal transmitted through the first electrode and the second electrode to control the interface.

The above aspects of the present invention are only some of the preferred embodiments of the present invention, and various embodiments reflecting the technical features of the present invention can be derived and understood by those skilled in the art based on the detailed description of the present invention to be described below.

The effects of the device according to the present invention are described as follows.

According to a liquid lens, a camera module, and an optical device according to one embodiment of the present invention, ghost and flare phenomena caused by light reflection at an interface between liquids having different properties and an inclined surface of an aperture area can be prevented without affecting the FOV (Field Of View) of the liquid lens.

The effects obtainable from the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from the description below.

Figure 1 illustrates an example of a camera module according to one embodiment of the present invention.
Figure 2 illustrates an example of a lens assembly included in a camera module.
Figure 3 illustrates a lens whose interface is adjusted in response to a driving voltage.
Figure 4 is a drawing explaining a phenomenon that may occur in a lens assembly including a liquid lens.
FIG. 5 is a drawing showing a liquid lens according to one embodiment of the present invention.
FIG. 6 is a drawing showing a liquid lens according to another embodiment of the present invention.
FIG. 7 is a drawing showing a liquid lens according to another embodiment of the present invention.

Hereinafter, embodiments will be described in detail with reference to the attached drawings. The embodiments may have various modifications and may take various forms, and specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the embodiments to a specific disclosed form, and it should be understood that it includes all modifications, equivalents, or substitutes included in the spirit and technical scope of the embodiments.

Although terms such as "first", "second", etc. may be used to describe various components, the components should not be limited by the terms. The terms are used for the purpose of distinguishing one component from another. In addition, terms specifically defined in consideration of the configuration and operation of the embodiment are only for the purpose of describing the embodiment, and do not limit the scope of the embodiment.

In the description of the embodiments, when it is described that each element is formed "on or under", "on or under" includes both cases where two elements are directly in contact with each other or where one or more other elements are formed by being disposed indirectly between the two elements. In addition, when expressed as "on or under", it can include the meaning of not only the upward direction but also the downward direction based on one element.

Additionally, relational terms such as “upper/upper/middle” and “lower/lower/bottom,” as used hereinafter, may be used to distinguish one entity or element from another, without necessarily requiring or implying any physical or logical relationship or order between such entities or elements.

Components indicated as having the same absence number in this specification may have the same structure, function and material.

Figure 1 illustrates an example of a camera module (10) according to one embodiment of the present invention.

Referring to FIG. 1, the camera module (10) may include a lens assembly (22) including a liquid lens and a plurality of lenses, a control circuit (24), and an image sensor (26).

The above liquid lens has a focal length adjusted in response to a driving voltage applied between a common electrode and a plurality of individual electrodes, the control circuit transmits a signal for supplying a driving voltage to the liquid lens, and the image sensor is aligned to the lens assembly (22) and converts light transmitted through the lens assembly (22) into an electric signal.

The camera module (10) may include a plurality of circuits (24, 26) arranged on a single printed circuit board (PCB) and a lens assembly (22) including a plurality of lenses, but this is only one example and does not limit the scope of the invention. The configuration of the control circuit (24) may be designed differently depending on the specifications required for the optical device. In particular, in order to reduce the size of the operating voltage applied to the lens assembly (22), the control circuit (24) may be implemented as a single chip. Through this, the size of the camera module mounted on the portable device can be further reduced.

Figure 2 illustrates an example of a lens assembly (22) included in a camera module (10).

Referring to FIG. 2, the lens assembly (22) may include a first lens unit (100), a second lens unit (200), a liquid lens unit (300), a holder (400), and a connecting unit (500). The structure of the illustrated lens assembly (22) is only one example, and the structure of the lens assembly (22) may vary depending on the specifications required for the camera module. For example, in the illustrated example, the liquid lens unit (300) is positioned between the first lens unit (100) and the second lens unit (200), but in other examples, the liquid lens unit (300) may be positioned above (in front of) the first lens unit (100), and the second lens unit (200) may be omitted.

The first lens unit (100) is arranged in front of the lens assembly (22) and is configured such that light is incident from the outside of the lens assembly (22). The first lens unit (100) may be composed of at least one lens, or two or more lenses may be aligned with respect to the central axis (PL) to form an optical system.

The first lens unit (100) and the second lens unit (200) can be mounted on the holder (400). At this time, a through hole is formed in the holder (400), and the first lens unit (100) and the second lens unit (200) can be placed in the through hole. In addition, a liquid lens unit (300) can be inserted into the space between the first lens unit (100) and the second lens unit (200) placed in the holder (400).

Meanwhile, the first lens unit (100) may include an exposure lens (110). In addition, the exposure lens (110) may protrude outside the holder (400). In the case of the exposure lens (110), the lens surface may be damaged due to being exposed to the outside. If the lens surface is damaged, the image quality of the image captured by the camera module may deteriorate. In order to prevent or suppress surface damage of the exposure lens (110), a method of arranging a cover glass, forming a coating layer, or configuring the exposure lens (100) with a wear-resistant material to prevent surface damage may be applied.

The second lens unit (200) is arranged behind the first lens unit (100) and the liquid lens unit (300), and light incident from the outside onto the first lens unit (100) can pass through the liquid lens unit (300) and be incident onto the second lens unit (200). The second lens unit (200) can be arranged in a through hole formed in the holder (400) apart from the first lens unit (100).

Meanwhile, the second lens unit (200) may be composed of at least one lens, and when two or more lenses are included, they may be aligned with respect to the central axis (PL) to form an optical system.

The liquid lens part (300) is positioned between the first lens part (100) and the second lens part (200) and can be inserted into the insertion hole (410) of the holder (400). The liquid lens part (300) can also be aligned with respect to the central axis (PL) like the first lens part (100) and the second lens part (200).

The liquid lens unit (300) may include a lens region (310). The lens region (310) is a region through which light passing through the first lens unit (100) is transmitted, and may include liquid in at least a portion thereof. For example, the lens region (310) may include two types of liquids, that is, a conductive liquid and a non-conductive liquid, and the conductive liquid and the non-conductive liquid may not mix with each other and may form a boundary. The boundary between the conductive liquid and the non-conductive liquid may be deformed by a driving voltage applied through the connecting portion (500), thereby changing the curvature and/or focal length of the liquid lens unit (300). When the deformation and curvature change of the boundary surface are controlled, the liquid lens unit (300) and the lens assembly (22) and camera module (10) including the liquid lens unit (300) can perform optical zoom functions, auto-focusing (AF) functions, and optical image stabilizer (OIS) functions.

FIG. 3 illustrates a lens whose interface is adjusted in response to a driving voltage. Specifically, (a) illustrates a liquid lens (28) included in a lens assembly (22, see FIG. 2), and (b) illustrates an equivalent circuit of the liquid lens (28).

First, referring to (a), the liquid lens (28) whose interface is adjusted in response to the driving voltage can receive the driving voltage through individual electrodes (L1, L2, L3, L4) arranged in four different directions with the same angular distance. When the driving voltage is applied through the individual electrodes (L1, L2, L3, L4), the boundary between the conductive liquid and the non-conductive liquid arranged in the lens area (310) can be deformed. The degree and shape of the deformation of the boundary between the conductive liquid and the non-conductive liquid can be controlled by the control circuit (24) to implement the AF function or the OIS function.

In addition, referring to (b), one side of the lens (28) can be described as receiving a driving voltage from different individual electrodes (L1, L2, L3, L4), and the other side can be described as a plurality of capacitors (30) connected to a common electrode (C0).

Although this specification exemplifies a case where there are four individual electrodes, the scope of the present invention is not limited thereto.

Figure 4 is a drawing explaining a phenomenon that may occur in a lens assembly including a liquid lens.

Referring to FIG. 4, when light is incident on a lens assembly (22) including a liquid lens, an approximate light path and an abnormal amount of light according to the incident angle of the light are illustrated.

The above light path illustrates examples of light at such angles of incidence that may cause ghosting or flare phenomena.

The above ghost phenomenon refers to a phenomenon in which, when strong light is directly incident on the lens, it is reflected on the lens barrel, etc., and an afterimage remains in the captured image, appearing blurred, and has the characteristic of an afterimage being formed along the shape of the perimeter of the aperture.

The above flare phenomenon refers to a phenomenon in which the captured image appears blurry due to light entering the lens being reflected on the lens barrel or due to diffuse reflection from an excessively bright subject.

The above ghost phenomenon and the above flare phenomenon are both mainly caused by light reflecting off the barrel of the lens, and can significantly deteriorate the quality of the image captured through the lens assembly (22).

The above abnormal light quantity refers to the ratio of the amount of light that causes the ghost phenomenon or the flare phenomenon among the amount of light incident on the lens assembly (22), and it can be seen that the abnormal light quantity increases as the incident angle increases in general. Of course, the ghost phenomenon and the flare phenomenon can be slowed down by the user appropriately adjusting the shooting angle, but the ghost phenomenon and the flare phenomenon that are severe at some angles can significantly deteriorate the quality of the camera module (10).

FIG. 5 is a drawing showing a liquid lens according to one embodiment of the present invention.

Referring to FIG. 5, the liquid lens (500) represents one embodiment of a cross-section of the liquid lens illustrated in FIG. 3.

The liquid lens (500) may include a conductive liquid (52), a non-conductive liquid (53), a plate, an electrode portion, an insulating layer (56), and an anti-reflection layer (60). The plate may include a first plate (54), and may further include a second plate (57) and a third plate (51). The electrode portion may include a first electrode (55-1), a second electrode (55-2), and the anti-reflection layer (60) may be a black insulating layer. In addition, the anti-reflection layer (60) may be a reflection-reducing layer that lowers reflectivity. Alternatively, the anti-reflection layer (60) may lower reflectivity for light corresponding to a specific range of wavelengths to below a specific reflectivity. For example, the anti-reflection layer (60) may lower reflectivity for light having a wavelength of 380 to 800 nm corresponding to visible light to below 5% or 10%.

The third plate (51) may be made of a transparent material and is configured to first receive light passing through the first lens unit (100, see FIG. 2) in the liquid lens (500). In this specification, it is assumed that the liquid lens (500) is the liquid lens (28) included in the lens assembly (22) of FIG. 2, but alternatively, the third plate (51) may be mounted in the lens assembly so as to be received last in the liquid lens (500). The third plate (51) may be placed below the first electrode (55-1), and the second plate (57) may be placed above the second electrode (55-2).

Conductive liquid (52) and non-conductive liquid (53) can be filled in a cavity determined by the opening area of the first plate (54). That is, conductive liquid (52) and non-conductive liquid (53) having different properties can be filled in the cavity, and an interface can be formed between conductive liquid (52) and non-conductive liquid (53) having different properties.

The interface formed by the conductive liquid (52) and the non-conductive liquid (53) can have the focal length or shape of the liquid lens (500) adjusted by changing the curvature, inclination, etc. The area through which the optical signal can pass through the interface can correspond to the lens area (310) described in Fig. 3.

Here, the conductive liquid (52) may include at least one of ethylene glycol and sodium bromide (NaBr), and may also be formed by mixing ethylene glycol and sodium bromide (NaBr), and the non-conductive liquid (53) may include a phenyl series silicone oil.

The first plate (54) is positioned between the third plate (51) and the second plate (57) and may include an opening area having a preset inclined surface (for example, an inclined surface having an angle of about 59 to 61 degrees). That is, the first plate (54) may include an inclined surface inside, and a conductive liquid (52) and a non-conductive liquid (53) may be placed on this inclined surface. The first plate (54) is a housing structure that confines two liquids with different properties within the liquid lens (500), and the third plate (51) and the second plate (57) include an area through which an optical signal passes, and thus may be formed of a material such as glass with high transparency, and for the convenience of the process (when bonding is performed using an intermediate layer of the same material, it is easy to prevent the liquid filling the cavity from flowing out), the first plate (54) may also be formed of a material such as glass. In another embodiment, the first plate (54) may include impurities to prevent easy transmission of an optical signal.

The first electrode (55-1) and the second electrode (55-2) can perform a function of applying an electric signal received from a control circuit (24, see FIG. 1) for controlling an interface formed by a conductive liquid (52) and a non-conductive liquid (53). The first electrode (55-1) can be arranged on an inclined surface of the first plate (54), and the second electrode (55-2) can be arranged on an upper portion of the first plate (54).

As described in FIG. 3, electrodes and/or electrode patterns for forming individual electrodes (L1, L2, L3, L4) and a common electrode (C0) may be included on both sides of the first plate (54) adjacent to the third plate (51) and the second plate (57). The second electrode (55-2) may be a common electrode positioned to contact the conductive liquid (52), and the first electrode (55-1) may be an individual electrode positioned to be close to the conductive liquid (52) with an insulating layer (56) therebetween.

Here, the first electrode (55-1) and the second electrode (55-2) may include chromium (Cr). Chromium or chromium is a hard transition metal with a silvery luster, and is characterized by being brittle, not easily discolored, and having a high melting point. However, since an alloy containing chromium is strong and resistant to corrosion, it can be used in the form of an alloy with other metals. In particular, since chromium (Cr) is less prone to corrosion and discoloration, it also has strong characteristics in the conductive liquid filling the cavity.

The insulating layer (56) is configured to physically insulate the first electrode (55-1) from the conductive liquid (52) and the non-conductive liquid (53). For example, the insulating layer (56) may include parylene C and may be implemented by a method such as coating, deposition, or plating.

The insulating layer (56) may be arranged to extend above the first plate (54) and below the non-conductive liquid (53), including an inclined surface that may come into contact with the conductive liquid (52) and the non-conductive liquid (53). The insulating layer (56) may be arranged above the first electrode (55-1). The insulating layer (56) may be arranged in a form that surrounds the first electrode (55-1) so that the first electrode (55-1) does not come into contact with the conductive liquid (52) on the upper part of the first plate (54) where the first electrode (55-1) and the second electrode (55-2) are arranged adjacent to each other, and may be arranged so that at least a portion of the insulating layer (56) comes into contact with the second electrode (55-2) as shown in FIG. 5, but the scope of the present invention is not limited thereto.

The second plate (57) can be formed of a transparent glass material and forms a cavity together with the third plate (51) and an opening area so that a conductive liquid (52) and a non-conductive liquid (53) can be filled.

The anti-reflection layer (60) may be disposed at a position where an interface between the conductive liquid (52) and the non-conductive liquid (53) is formed along the inclined surface of the aperture area, and on top of the first electrode (55-1) and the insulating layer (56). In addition, the anti-reflection layer (60) may be disposed so as to contact an edge interface (IF) adjacent to the insulating layer (56). That is, the anti-reflection layer (60) may be disposed so as to contact the edge interface (IF) at the outermost edge of the inclined surface of the aperture area. Accordingly, the interface between the conductive liquid (52) and the non-conductive liquid (53) may move along the insulating layer (56-1) disposed on the inclined surface. In addition, the anti-reflection layer (60) may be disposed so as not to overlap with the aperture surface (D), which is an area through which light passes under the non-conductive liquid (53). This is to prevent the FOV (Field Of View) of the liquid lens (500) from being affected by the anti-reflection layer (60).

The anti-reflection layer (60) may be implemented with a material that does not reflect light (e.g., a graphite coating or a soma film) or a material having a light reflectivity lower than that of the insulating layer. The anti-reflection layer (60) may be disposed by a process of coating, plating, or depositing a graphite material on top of the insulating layer (56), or by a process of bonding a soma film to the insulating layer (56). According to another embodiment, the anti-reflection layer (60) may include a black resin.

For example, the thickness of the insulating layer (56) may be about 0.5 to 15 μm or about 1 to 10 μm. The thickness of the anti-reflection layer (60) may be about 0.5 to 10 μm or about 1 to 5 μm.

Since ghost and flare phenomena are most likely to occur due to reflections occurring at the edge interface (IF) and the slope of the aperture area, ghost and flare phenomena can be prevented by including an anti-reflection layer (60) that prevents light reflection in these areas or lowers light reflectance.

In addition, the anti-reflection layer (60) may be arranged to extend to the upper portion of the first plate (54), and prevents light reflected and/or passed through the third plate (51), the first plate (54), the electrode layer (55), or the insulating layer (56) from being transmitted to the second plate (57), thereby preventing deterioration of the image quality caused by light transmitted through the liquid lens (500). Or, conversely to the embodiment, the light passing from the second plate (57) to the third plate (51) may be prevented from being deteriorated in the image quality by the anti-reflection layer (60).

The anti-reflection layer (60) extending to the upper portion of the first plate (54) does not necessarily need to be arranged to be in contact with the conductive liquid (52) or the second plate (57) within the range having the above-mentioned effect, and the anti-reflection layer may also be arranged between two adjacent layers among the first plate (54), the electrode layer (55), and the insulating layer (56).

FIG. 6 is a drawing showing a liquid lens according to another embodiment of the present invention.

Referring to FIG. 6, a liquid lens (600) represents another embodiment of a cross-section of the liquid lens illustrated in FIG. 3.

The anti-reflection layer (61-1) included in the liquid lens (600) may be disposed at a position where an interface between the conductive liquid (52) and the non-conductive liquid (53) is formed along the inclined surface of the aperture area, similar to the anti-reflection layer (60) included in the liquid lens (500) of FIG. 5, and on top of the first electrode (55-1) and the insulating layer (56). In addition, the anti-reflection layer (61-1) may be disposed so as to contact an edge interface (IF) adjacent to the insulating layer (56). That is, the anti-reflection layer (61-1) may be disposed so as to contact the edge interface (IF) at the outermost edge of the inclined surface of the aperture area. Accordingly, the interface between the conductive liquid (52) and the non-conductive liquid (53) may move along the insulating layer (56) disposed on the inclined surface. Additionally, the anti-reflection layer (61-1) may be positioned so as not to overlap with the opening (D) at the bottom of the non-conductive liquid (53). This is to prevent the FOV (Field Of View) of the liquid lens (500) from being affected by the anti-reflection layer (61-1).

The antireflection layer (61-1, 61-2) may be implemented with a material that does not reflect light (e.g., a graphite coating or a Soma film) or a material having a light reflectivity lower than that of the insulating layer. The antireflection layer (60) may be disposed by a process of coating, plating, or depositing a graphite material on top of the insulating layer (56), or may be disposed by a process of bonding a Soma film to the insulating layer (56). According to another embodiment, the antireflection layer (61-1, 61-2) may include a black resin.

For example, the thickness of the insulating layer (56) may be about 0.5 to 15 μm or about 1 to 10 μm. The thickness of the anti-reflection layer (61-1, 61-2) may be about 0.5 to 10 μm or about 1 to 5 μm.

Since ghost and flare phenomena are most likely to occur due to reflections occurring at the edge interface (IF) and the slope of the aperture area, ghost and flare phenomena can be prevented by including an anti-reflection layer (61-1) that prevents light reflection in these areas or lowers light reflectance.

In addition, the anti-reflection layer (61-2) can be arranged to extend so as not to overlap with the opening surface (D) at the bottom of the first plate (54), and prevents light reflected and/or transmitted through the third plate (51) from being transmitted to the first plate (54), the electrode layer (55), the insulating layer (56), or the second plate (57), thereby preventing deterioration of the image quality caused by light transmitted through the liquid lens (500). Or, conversely to the embodiment, the light passing from the second plate (57) to the third plate (51) can be prevented from deteriorating the image quality due to the anti-reflection layer (61-2).

The anti-reflection layer (61-2) extending to the lower portion of the first plate (54) does not necessarily need to be arranged to be in contact with the third plate (51) within the range having the above-mentioned effect, and the anti-reflection layer may also be arranged between the first electrode (55-1) and the first plate (54).

FIG. 7 is a drawing showing a liquid lens according to another embodiment of the present invention.

Referring to FIG. 7, a liquid lens (700) represents another embodiment of a cross-section of the liquid lens illustrated in FIG. 3.

Unlike the liquid lens of FIG. 5 or 6, the liquid lens (700) may not include a separate anti-reflection layer. That is, the liquid lens (700) may have the insulating layer (56-1) itself perform the anti-reflection or reflection reduction function. Meanwhile, the insulating layer (56-1) may be defined as a black insulating layer.

The insulating layer (56-1) may be arranged on top of the first electrode (55-1) along the inclined surface of the first plate (54). Additionally, the insulating layer (56-1) may be arranged to extend along the lower or upper portion of the first plate (54).

That is, the insulating layer (56-1) may be implemented with a parylene C coating agent, but the insulating layer (56-1) may include a black resin to reduce light transmittance. The black resin may be implemented with a material having excellent light absorbency and low chemical reactivity with parylene C. In addition, the black resin may be an antireflection resin or a reflection reduction resin. According to another embodiment, the insulating layer (56-1) may be implemented with a graphite coating, a Soma film, or a material having a light reflectivity lower than that of the insulating layer. The insulating layer (56-1) may be disposed by a process of coating, plating, or depositing a graphite material on the upper portion of the first electrode (55-1), or by a process of bonding the Soma film to the first electrode (55-1).

The insulating layer (56-1) including the black resin can be arranged at a position where an interface between the conductive liquid (52) and the non-conductive liquid (53) is formed. In addition, the insulating layer (56-1) can be arranged to contact the edge interface (IF). That is, the insulating layer (56-1) can be arranged to contact the edge interface (IF) at the outermost edge of the inclined surface of the opening region. Accordingly, the interface between the conductive liquid (52) and the non-conductive liquid (53) can move along the insulating layer (56-1) arranged on the inclined surface. In addition, the insulating layer (56-1) can be arranged so as not to overlap with the opening surface (D) below the non-conductive liquid (53). This is to prevent the FOV of the liquid lens (500) from being affected by the insulating layer (56-1).

In addition, an insulating layer (56-2) that does not include black resin may be additionally placed on the non-conductive liquid (53) and the third plate (51) for the area through which light passes, in which case the insulating layer (56-2) may be a transparent insulating layer with high light transmittance. In addition, the thicknesses of each of the insulating layers (56-1, 56-2) may be the same, or, in order to adjust the control range of the interface, the thickness of the insulating layer (56-1) may be thicker or thinner than the thickness of the insulating layer (56-2), depending on the material of the insulating layer (56-1).

For example, the thickness of the insulating layer (56-1) including black resin may be about 0.5 to 20 μm or about 1 to 15 μm, and the thickness of the insulating layer (56-2) not including black resin may be about 0.5 to 15 μm or about 1 to 10 μm.

Since ghost and flare phenomena are most likely to occur due to reflections occurring at the edge interface (IF) and the slope of the aperture area, the insulating layer (56-1) that prevents light reflection in these areas includes black resin, thereby preventing ghost and flare phenomena. As a result, ghost and flare phenomena can be reduced without deforming the original liquid lens structure.

In addition, the insulating layer (56-1) may be arranged to extend to the upper portion of the first plate (54), and prevent light reflected and/or transmitted through the third plate (51), the first plate (54), the electrode layer (55), or the insulating layer (56) from being transmitted to the second plate (57), thereby preventing deterioration of the image quality caused by light transmitted through the liquid lens (500). Or, conversely to the embodiment, the light passing from the second plate to the third plate may be prevented from being deteriorated in the image quality by the anti-reflection layer.

The material of the black resin mentioned in FIGS. 5 to 7 may be carbon nanotubes (CNT) and/or polyamide. In addition, the black resin may be included in the liquid lens through a sputtering process, an E-beam process, and/or a chemical vapor deposition (CVD) process.

Below, the configuration of the camera module according to the present embodiment is described.

The camera module may include a lens assembly including a liquid lens, an infrared cut filter (not shown), a printed circuit board (not shown), an image sensor (not shown), and a control unit (not shown). However, in the camera module, at least one of the infrared cut filter and the control unit may be omitted or changed.

The infrared filter can block infrared light from entering the image sensor. The infrared filter can be placed between the lens assembly and the image sensor. The infrared filter can be an infrared absorption filter or an infrared reflection filter. In addition, the infrared filter can be formed by coating or depositing on one side of the liquid lens without being placed separately.

The upper surface of the printed circuit board and the liquid lens may be electrically connected. An image sensor may be arranged on the printed circuit board. The printed circuit board may be electrically connected to the image sensor. For example, a holder member may be arranged between the printed circuit board and the lens assembly. At this time, the holder member may accommodate an image sensor on the inside. The printed circuit board may supply power (current or voltage) to the liquid lens. Meanwhile, a control unit for controlling the liquid lens may be arranged on the printed circuit board.

Below, the configuration of the optical device according to the present embodiment is described.

The optical device may be any one of a mobile phone, a cellular phone, a smart phone, a portable smart device, a digital camera, a laptop computer, a digital broadcasting terminal, a PDA (Personal Digital Assistants), a PMP (Portable Multimedia Player), and a navigation device. However, the type of the optical device is not limited thereto, and any device for taking images or photographs may be referred to as an optical device.

The optical device may include a main body (not shown), a camera module, and a display unit (not shown). However, in the optical device, one or more of the main body, the camera module, and the display unit may be omitted or changed.

As described above with respect to the embodiments, only a few have been described, but various other forms of implementation are possible. The technical contents of the embodiments described above can be combined in various forms as long as they are not mutually incompatible technologies, and can be implemented as new embodiments through this.

It will be apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential characteristics of the present invention. Accordingly, the above detailed description should not be construed as limiting in all aspects, but should be considered as illustrative. The scope of the present invention should be determined by a reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

Claims (10)

A first plate comprising a sloped surface therein;
Conductive liquid and non-conductive liquid placed on the above inclined surface;
A first electrode disposed on the above inclined surface;
A second electrode disposed on the upper portion of the first plate;
A third plate disposed below the first plate;
A transparent insulating layer disposed between the third plate and the non-conductive liquid, but not in contact with the conductive liquid but only in contact with the non-conductive liquid; and
A black insulating layer is disposed on top of the first electrode along the inclined surface and connected to both ends of the transparent insulating layer so as not to overlap with the lower part of the non-conductive liquid;
A liquid lens in which the interface formed by the conductive liquid and the non-conductive liquid moves along the black insulating layer disposed on the inclined surface. In the first paragraph,
The above black insulating layer is a liquid lens arranged so as not to overlap with the lower part of the non-conductive liquid. In the first paragraph,
The above black insulating layer is a liquid lens arranged in contact with the first electrode and the second electrode. delete In the first paragraph,
A liquid lens in which the thicknesses of the transparent insulating layer and the black insulating layer are the same. In the first paragraph,
The above black insulating layer is a liquid lens that is arranged to extend along the lower or upper portion of the first plate. In the first paragraph,
The above black insulating layer is a liquid lens containing graphite or Soma film or black resin. A first plate including an opening area having a preset slope;
Conductive liquid and non-conductive liquid placed on the above inclined surface;
A first electrode disposed on the above inclined surface;
A second electrode disposed on the upper portion of the first plate;
A third plate disposed below the first electrode;
A second plate disposed on top of the second electrode;
An insulating layer disposed on top of the first electrode; and
Including an anti-reflection layer disposed on the upper part of the insulating layer but not in contact with the second plate;
The above anti-reflection layer is,
A first anti-reflection layer disposed on top of the insulating layer along the slope so as not to overlap with the lower part of the non-conductive liquid; and
It comprises a second anti-reflection layer disposed between the first electrode and the first plate,
A liquid lens positioned at a position where an interface between the conductive liquid and the non-conductive liquid is formed along the inclined surface, thereby preventing reflection by the inclined surface. In Article 8,
The above anti-reflection layer is a liquid lens containing graphite or Soma film or black resin. A liquid lens according to any one of claims 1 to 3 and claims 5 to 9;
An image sensor that converts light transmitted through the liquid lens into an electrical signal; and
A camera module comprising a control circuit for transmitting an electric signal for controlling the interface through the first electrode and the second electrode.