KR20220015581A - Camera module - Google Patents

Abstract

A camera module disclosed in an embodiment of the invention may include: a substrate; an image sensor disposed on the substrate; a first lens group including at least one lens on the image sensor; a second lens group including a plurality of lenses between the first lens group and the image sensor; a first lens holder supporting the first lens group; a second lens holder supporting the second lens group in the first lens holder; and a driving part for moving the second lens holder in an optical axis direction.

Description

Camera Module {CAMERA MODULE}

An embodiment of the invention relates to a camera module.

An embodiment of the invention relates to a camera module that can be mounted on a portable terminal.

A user of a portable device wants an optical device having a high resolution, small size, and various shooting functions, for example, an auto-focusing (AF) function, or an optical image stabilizer (OIS) function. are doing Such a photographing function may be implemented through a method of directly moving a lens by combining a plurality of lenses, but if the number of lenses is increased, the size of the optical device may increase.

In order to improve the performance of the camera module, it is necessary to improve the performance of the imaging optical system and the image sensor. However, the camera module mounted on the portable terminal is not easy to improve the performance of the imaging optical system and the image sensor due to the spatial limitation of the portable terminal. For example, in order to implement a high-resolution camera module, it is difficult to enlarge the image sensor of the camera module. Therefore, in order to implement a high-resolution camera module, it is necessary to develop a bright imaging optical system having a wide angle of view and having an F number of 2.0 or less.

An embodiment of the present invention may provide a camera module for adjusting the focus by moving the image-side second lens group without moving the object-side first lens group.

An embodiment of the present invention may provide a camera module for adjusting the focus by moving the image-side second lens group in the optical axis direction based on the object-side first lens group.

An embodiment of the present invention may provide a camera module in which a first lens group having at least one lens and having a fixed position and a second lens group having at least one lens and having a position to be moved are aligned along an optical axis.

An embodiment of the present invention may provide a camera module and a mobile device having the same.

A camera module according to an embodiment of the present invention includes a substrate; an image sensor disposed on the substrate; a first lens group including at least one lens on the image sensor; a second lens group including a plurality of lenses between the first lens group and the image sensor; a first lens holder supporting the first lens group; a second lens holder supporting the second lens group in the first lens holder; and a driving unit for moving the second lens holder in an optical axis direction.

According to an embodiment of the present invention, stoppers for limiting movement of the second lens holder may be respectively provided on upper and lower portions of the first lens holder.

According to an embodiment of the present invention, the driving unit may include an actuator having a movable member disposed outside the second lens holder and a fixing part facing the movable member inside the first lens holder.

According to an embodiment of the present invention, the first lens group may include 3 or less lenses, and the second lens group may include 2 to 5 lenses.

According to an embodiment of the present invention, the total refractive power of the second lens group may have a negative refractive power.

According to an embodiment of the present invention, the TTL in the camera module may be in the range of 4 mm to 10 mm, the effective focal length may be in the range of 3 mm to 10 mm, and the movement amount of the second lens group may be in the range of 0.05 mm to 1 mm.

According to an embodiment of the present invention, the first lens group includes a first lens, the second lens group includes second to sixth lenses aligned from the object side to the image side, and the refractive index of the first lens may be higher than the refractive index of the second to sixth lenses.

According to an embodiment of the present invention, the Abbe numbers of the second and sixth lenses may be lower than the Abbe numbers of the first, 3, 4, and 5 lenses, and the Abbe numbers of the third, 4, and 5 lenses may be 50 or more. there is.

According to an embodiment of the present invention, the first lens may have a positive refractive power, and the sixth lens may have a negative refractive power. The first to sixth lenses may be formed of a plastic material.

According to an embodiment of the present invention, the size of the camera module can be reduced by focusing by moving some lens units within the camera module.

According to an embodiment of the present invention, without moving the lens(s) close to the subject, by moving the lenses close to the image side to focus, it is possible to reduce the movement space of the lens.

According to an embodiment of the present invention, it is possible to provide a slim AF optical system.

According to an embodiment of the invention, a high-resolution camera module can be implemented.

1 is an example of lens optical systems of a camera module according to an embodiment of the present invention.
FIG. 2 is a view for explaining an incident surface and an exit surface of each lens in the lens optical system of FIG. 1 .
3 is a view for explaining a driving example of a second lens group of the camera module having the lens optical system of FIG. 1 .
4 is a diagram illustrating an example of a lens optical system in a camera module according to an embodiment of the present invention.
5 is a graph for explaining the module size in the AF stroke according to the diagonal length of the image sensor in the camera module.
6 is a view comparing the sizes of the lens module and the second lens group according to the increase in the diagonal size of the image sensor in the camera module according to the embodiment of the present invention.
7 is an example of a mobile device having a plurality of camera modules according to an embodiment of the present invention.

Hereinafter, a preferred embodiment of the present invention will be described in detail based on the accompanying illustrative drawings. In describing the present invention below, terms referring to the components of the present invention are named in consideration of the function of each component, and thus should not be construed as limiting the technical components of the present invention. Throughout the specification, the 'connection' of a certain component to another component includes not only a case in which these components are 'directly connected' but also a case in which the component is 'indirectly connected' with another component interposed therebetween. do. In addition, 'including' a certain component means that other components may be further included, rather than excluding other components, unless otherwise stated.

An optical zoom function (zoom-in/zoom-out), autofocusing (zoom-in/zoom-out), autofocusing (zoom-in/zoom-out), autofocusing (zoom-in/zoom-out) It is not easy to implement an Auto-Focusing (AF) function, image stabilization or optical image stabilization (OIS) function.

In the description of the invention, the first lens means the lens closest to the object side, and the last lens means the lens closest to the image side (or sensor surface). In the description of the invention, all units for the radius, thickness/distance, TTL, etc. of the lens are mm unless otherwise specified. In the present specification, the shape of the lens is shown based on the optical axis of the lens. For example, the meaning that the object side of the lens is convex means that the vicinity of the optical axis is convex on the object side of the lens, but does not mean that the vicinity of the optical axis is convex. Accordingly, even when it is described that the object side of the lens is convex, the portion around the optical axis on the object side of the lens may be concave. In the present specification, it should be noted that the thickness and radius of curvature of the lens are measured based on the optical axis of the lens.

In addition, the convex surface of the lens may mean that the lens surface of the region corresponding to the optical axis has a convex shape, and the concave lens surface means that the lens surface of the region corresponding to the optical axis has a concave shape can do. In addition, "object-side surface" may mean a surface of the lens that faces the object side with respect to the optical axis, and "image-side surface" may mean a surface of the lens that faces the imaging surface with respect to the optical axis.

1 is an example of lens optical systems of a camera module according to an embodiment of the present invention, FIG. 2 is a view for explaining an incident surface and an exit surface of each lens in the lens optical system of FIG. 1, and FIG. 3 is the lens optical system of FIG. It is a view for explaining an example of driving the second lens group of the camera module having

1 to 3 , a camera module according to an embodiment of the present invention may include four or more lenses or five or more lens optical systems. The camera module may include a first lens group 110 having at least one lens 111 on the object side, and a second lens group 120 having a plurality of lenses 121 , 122 , 123 , 124 , and 125 on the image side.

The first lens group 110 may be disposed between the object and the second lens group 120 , and the second lens group 120 may be disposed between the first lens group 110 and the image sensor 190 . there is. The first lens group 110 may include one or more lenses 111 , and may be less than or equal to the number of lenses in the second lens group 120 , for example, the number of lenses in the second lens group 120 is the second. The number of lenses in one lens group 110 may be equal to or greater than the number of lenses. The first lens group 110 may be stacked with 1 to 3 lenses, and the second lens group 120 may be stacked with 2 to 5 lenses.

The lenses 111 of the first lens group 110 may be solid lenses, for example, a plastic material or a glass material. The second lens group 120 includes a plurality of lenses 121 , 122 , 123 , 124 , and 125 , and may be solid lenses, and may be made of plastic or glass. At least one of the lenses 111 , 121 , 122 , 123 , 124 and 125 may be made of glass, and the rest may be made of plastic. As another example, at least one of the lenses 111 , 121 , 122 , 123 , 124 and 125 may be made of a plastic material, and the rest may be made of a glass material. The lenses 111 , 121 , 122 , 123 , 124 , and 125 may all be made of a plastic material.

The lens optical system according to the present invention may include five or more lenses (111,121,122,123,124,125), the first lens 111, the second lens 121, the third lens 122, which are sequentially arranged from the object side to the image side; It may include a fourth lens 123 , a fifth lens 124 , and a sixth lens 125 . The camera module may include a filter 192 and an image sensor 190 in an upper direction of the second lens group 120 .

Such a lens optical system and a camera module having the same may be applied to a mobile terminal. However, the lens optical system in the mobile terminal has a function of automatically focusing on an object or subject in order to implement the AF function. In the general AF function, the entire lens moves toward the subject while the position of the subject moves from the far side to the near side. Accordingly, when the camera module is mounted in the mobile terminal, the moving distance of the lens is also considered, and the higher the performance, the larger the space is required.

An embodiment of the present invention may provide an optical system capable of focusing by moving only some lenses without moving a lens close to the subject when the position of the subject moves from the near side to the far side. That is, by providing an optical system for focusing by moving only the image side lens group without moving the object side lens group, it is possible to relatively suppress an increase in space or a moving distance.

1 , the first lens group 110 may be fixed in position, and the second lens group 120 may be moved (M1) in the optical axis Lx direction. That is, it is possible to move the lens holder 153 having the second lens group 120 in the optical axis direction. The second lens group 120 may move toward the first lens group 110 along the optical axis Lx or toward the image sensor 190 . The first lens group 110 and the second lens group 120 may be focused by the movement M1 of the second lens group 120 .

Since the at least one first lens 111 closest to the object side is fixedly positioned, a distance from the image sensor 190 may be constant. At least one or all of the second to sixth lenses 121 , 122 , 123 , 124 , and 125 disposed between the first lens 111 and the image sensor 190 move toward the first lens 111 or toward the image sensor 190 . can move Accordingly, the distance between the object-side surface of the second to sixth lenses 121 , 122 , 123 , 124 and 125 and the first lens 111 may be varied, and the distance between the image-side surface and the image sensor 190 may be varied. By moving the second to sixth lenses 121 , 122 , 123 , 124 , and 125 , the light incident through the first lens 111 may be adjusted to be focused on the image sensor 190 . Accordingly, the effective focal length may be changed. The effective focal length (EFL) of the lens optical system of the present invention may be 20 mm or less, for example, in the range of 3 mm to 10 mm, and the amount of change in the effective focal length by the second lens group 120 may be 10% or less, for example 2 mm or less or in the range of 0.05 mm to 1 mm. Here, the TTL (Total Top Length) of the lens optical system may be 10 mm or less, for example, 3 mm to 10 mm.

In addition, the refractive power of the second lens group 120 may have a negative refractive power, and may have a power different from that of the first lens group 110 . Accordingly, it is possible to focus without increasing the TTL by the second lens group 120 .

The first to sixth lenses 111 , 121 , 122 , 123 , 124 , and 125 may be sequentially disposed along the optical axis Lx of the optical system. The light corresponding to the image information of the object is the first lens 111 , the second lens 121 , the third lens 122 , the fourth lens 123 , the fifth lens 124 , and the sixth lens 125 . ) and passing through the filter 192 may be incident on the image sensor 190 .

Each of the first to sixth lenses 111 , 121 , 122 , 123 , 124 , and 125 may include an effective area and an ineffective area. The effective area may be an area through which light incident on each lens passes. That is, the effective region may be a region in which incident light is refracted to realize optical properties. The ineffective area may be disposed around the effective area. The ineffective area may be an area to which the light is not incident. That is, the ineffective region may be a region independent of the optical characteristic. Also, the ineffective region may be a region fixed to a lens holder or a barrel (not shown) for accommodating lenses.

The optical system according to an embodiment of the present invention may include a stopper ST for adjusting the amount of incident light. The diaphragm ST may be disposed on an image side surface or a water side surface of any one of the first to fourth lenses 111 , 121 , 122 , 123 and 124 . The diaphragm is disposed on the periphery of the surface of the lens close to the first lens 111 in the second lens group 120 , for example, between the third and fourth lenses 122 and 123 , so that the amount of light can be adjusted. The first to sixth lenses 111, 121, 122, 123, 124, and 125 may be lenses made of a plastic material, and these plastic lenses may have a higher refractive index than a glass material and may be provided as an aspherical surface, so that it is easy to control the path of the incident light. .

Referring to FIG. 2 , the first lens 111 may have positive (+) refractive power. The first lens 111 may include a plastic material. The first lens 111 may include a first surface S1 defined as an object-side surface and a second surface S2 defined as an image-side surface. The first surface S1 may be an incident surface, and the second surface S2 may be an exit surface. The first surface S1 may be convex and the second surface S2 may be concave. That is, the first lens 111 may have a meniscus shape convex toward the object. At least one or both of the first surface S1 and the second surface S2 may be aspherical. Alternatively, the second surface S2 may be flat.

The effective radius of the first lens 111 may be greater than the effective radius of the second to fourth lenses 121 , 122 , 123 , and 124 with respect to the optical axis. Accordingly, the amount of ambient light may be improved.

The second lens 121 may have positive (+) or negative (-) refractive power. The second lens 113 may include a plastic material. The second lens 121 may include a third surface S3 defined as an object-side surface and a fourth surface S4 defined as an image-side surface. The third surface S3 may be an incident surface, and the fourth surface S4 may be an exit surface. The third surface S3 may be concave upward, and the fourth surface S4 may be convex upward. At least one or both of the third surface S3 and the fourth surface S4 may be aspherical.

The third lens 122 may have positive (+) or negative (-) refractive power. The third lens 122 may include a plastic material. The third lens 122 may include a fifth surface S5 defined as an object-side surface and a sixth surface S6 defined as an image-side surface. The fifth surface S5 may be an incident surface, and the sixth surface S6 may be an exit surface. The fifth surface S5 may be convex toward the water side and the sixth surface S6 may be concave toward the water side. At least one of the fifth surface S5 and the sixth surface S6 may be a spherical surface or an aspherical surface. For example, both the fifth surface S5 and the sixth surface S6 may be aspherical.

The fourth lens 123 may have positive (+) or negative (-) refractive power. The fourth lens 123 may include a plastic material. The fourth lens 124 may include a seventh surface S7 defined as an object-side surface and an eighth surface S8 defined as an image-side surface. The seventh surface S7 may be an incident surface, and the eighth surface S8 may be an exit surface. The seventh surface S7 may be flat or concave upward, and the eighth surface S8 may be convex upward. At least one of the seventh surface S7 and the eighth surface S8 may have an inflection point around the center. Both the seventh and eighth surfaces S7 and S8 may be aspherical.

The fifth lens 124 may have positive (+) or negative (-) refractive power. The fourth lens 124 may include a plastic material. The fifth lens 124 may include a ninth surface S9 defined as an object-side surface and a tenth surface S10 defined as an image-side surface. The ninth surface S9 may be an incident surface, and the tenth surface S10 may be an exit surface. The ninth surface S9 may be concave upward, and the tenth surface S10 may be convex upward. At least one of the ninth surface S9 and the tenth surface S10 may have an inflection point around the center. At least one or both of the ninth and tenth surfaces S9 and S10 may be aspherical.

The sixth lens 125 may have a negative refractive power. For example, the sixth lens 126 may include a plastic material. The fifth lens 125 may include an eleventh surface S11 defined as an object-side surface and a twelfth surface S12 defined as an image-side surface. The eleventh surface S11 may be an incident surface, and the twelfth surface S12 may be an exit surface. The eleventh surface S11 may be concave upward, and the twelfth surface S12 may be concave toward the object. That is, the eleventh surface S11 may have a shape in which a center region is concave upward, and a region around the center has a convex shape toward the object. The twelfth surface S12 may have a center region concave toward the object, an area around the center convex toward the sensor, and an edge region concave toward the object. The eleventh surface S11 of the sixth lens 125 may include an aspherical surface, and may include at least one or a plurality of inflection points. The twelfth surface S12 may include an aspherical surface, and may include at least one or a plurality of inflection points.

The filter 192 may include at least one of an infrared filter and an optical filter such as a cover glass. The filter 192 may pass light of a set wavelength band and filter light of a different wavelength band. When the filter 192 includes an infrared filter, radiant heat emitted from external light may be blocked from being transmitted to the image sensor. In addition, the filter 192 may transmit visible light and reflect infrared light.

The image sensor 190 may detect light passing through the filter 192 and/or the sixth lens 125 . The image sensor 190 may include a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS).

Also, looking at the relative refractive index at 587 nm of the lens in the lens optical system, the first lens 111 has a high refractive index, and the second lens 121 has a low refractive index compared to the refractive index of the first lens 111, and the third to The fifth lenses 122 , 123 , and 124 have a lower refractive index than that of the second lens 121 , and the difference between the refractive indices may be at most 0.1 or less. In the sixth lens 125 , the third to fifth lenses 122 , 123 , and 124 may have a higher refractive index than that of the second lens 121 .

Also, looking at the Abbe number in the d-line (587 nm) of the lens in the lens optical system, the Abbe number of the first lens 111 is greater than the Abbe number of the second lens 121, for example, 1.5 times or more. can be large The Abbe's number of the second lens 121 may be smaller than the Abbe's number of the first lens 111 and the third lens 122 , and may be, for example, 25 or less. The Abbe's number of the third to fifth lenses 122 , 123 , and 124 may be 50 or more. Also, the Abbe's number of the sixth lens 124 may be smaller than the Abbe's number of the fifth lens 123 , and a difference from the Abbe's number of the second lens 121 may be 10 or less or 5 or less.

The Abbe's number of the first, 3, 4, and 5 lenses 111 , 121 , 122 , 123 and 124 may be 35 or more. The Abbe's number in the lens is decreased when the refractive index of the lens is increased, and when the Abbe's number is small, color dispersion is effective, and when the Abbe's number is large, the color dispersion is small. If the Abbe's number in the lens is high, chromatic aberration may be small and transparency may be improved.

Table 1 shows the lens characteristics of the lens optical system according to the embodiment.

first embodiment noodle # Radius Surface type Thickness/
Interval Index Abbe # first lens S1 2.595 ASP 1.002 1.70 41.60 S2 1.00E+18 ASP 0.210 (variable) second lens S3 1.00E+18 ASP 0.250 1.66 20.40 S4 2.747 ASP 0.178 third lens S5 1.822 ASP 0.320 1.54 56.00 S6 1.485 ASP 0.0714 4th lens S7 2.377 ASP 0.509 1.54 56.00 S8 9.385 ASP 0.423 5th lens S9 49.53 ASP 0.350 1.54 56.00 S10 3.577 ASP 0.559 6th lens S11 -11.691 ASP 0.846 1.66 20.40 S12 -7.531 ASP 0.202 (variable) filter S13 Infinity SPH 0.110 1.52 64.20 S14 Infinity SPH 0.452 image sensor Image Infinity SPH 0.000

In Table 1, the ASP represents the aspherical surface, SPH represents the power (Sphere), and the thickness in the items of each surface (S1, S3, S5, S7, S9, S11) is the thickness at the optical axis of each lens. , and the spacing indicates the spacing between two lenses aligned with the optical axis. The thickness of S13 may be the thickness of the filter, and the thickness of the Image may be the thickness of the image sensor.

An interval between the first lens 111 and the second lens 121 may be small or large from the first interval to the second interval. For example, when the first interval is in the range of 0.210 mm±0.01 mm (initial interval), when the second lens group 120 moves toward the object side, the interval may be reduced to 0.226 mm±0.01 mm. That is, since the second lens group 120 moves closer in the direction of the second surface S2 of the first lens 111 , the distance may be reduced and focus may be achieved.

When the second lens group 120 moves to the image side, the interval between the twelfth surface S12 of the second lens group 120 or the sixth lens 125 and the filter 192 is 0.202 mm±0.01 mm It can be reduced to 0.196mm±0.01mm based on (initial spacing).

In this way, the lens optical system moves all of the second to sixth lenses 121 , 122 , 123 , 124 , and 125 of the second lens group 120 in the optical axis direction without moving the first lens 111 or the first lens group 110 . , it is possible to suppress the problem that the length or space of the lens optical system is increased. Also, as the size of the image sensor 190 increases, it is possible to solve the problem that the length of the lens optical system increases according to the position of the object.

Referring to FIG. 3 , the camera module supports the substrate 195 on which the image sensor 190 is disposed, the first lens holder 150 supporting the first lens group 110 , and the second lens group 120 . It may include a second lens holder 153, and driving units (155, 156).

The substrate 195 may be a flexible or non-flexible substrate, and may be implemented as an FPCB. An image sensor 190 is mounted on the substrate 195 , and a lower end of the first lens holder 150 may be coupled to the periphery.

The first lens group 110 is supported on the upper part 152 of the first lens holder 150 , for example, the outer circumference of the first lens 111 is supported. The first lens holder 150 has a through hole 151 passing through it, and the first lens 111 is positioned on the through hole 151 .

A second lens holder 153 supporting the second lens group 153 is disposed inside the through hole 151 or inside the first lens holder 150 . The second lens holder 153 is disposed between the first lens group 110 and the image sensor 190, and moves in the optical axis direction when performing an Auto Focusing (hereinafter, AF) function (M1). can be The second lens holder 153 may be supported by an elastic spring, and may be supported when moving in the optical axis direction.

The driving units 155 and 156 may be disposed outside or/and around the lower portion of the second lens holder 153, and may be disposed in an area that does not obstruct the path of the light. The driving units 155 and 156 may include at least one of a piezo member, an actuator, and a stamping motor. The driving units 155 and 156 may move the second lens holder 153 in the optical axis direction. For example, the piezo member may control the amount of movement of the second lens holder 153 that linearly moves according to a physical displacement caused by an applied electric field.

The driving units 155 and 156 may include an actuator including a mover 155 disposed outside the second lens holder 153 and a stator 156 disposed inside the first lens holder 150 . there is. When the mover 155 is a magnet, the stator 156 may be a coil. As another example, when the mover 155 is a coil, the stator 156 may be a magnet.

When external power is applied to the driving units 155 and 156 , a magnetic field is formed between the driving unit 155 and the movable element 155 according to the polarity of the power applied to the stator 156 . At this time, the mover 155 moves toward the first lens group 110 or toward the image sensor 190 along the optical axis together with the second lens holder 153, and the second lens group ( By the movement of the 120 , the light incident through the first lens group 110 may be focused on the image sensor 190 .

Here, the camera module may include stoppers 161 and 162 that limit the movement of the second lens group 120 . The stopper 161 may include a first stopper 161 at a lower portion and a second stopper 162 at an upper portion. The material of the first and second stumps 161 and 162 may be a metal or a non-metal material. The material of the first and second stoppers 161 and 162 may be an elastic metal or an inelastic material.

The first stopper 161 may be disposed around the image sensor 190 and protrude higher than an upper end of the filter 192 . The first stopper 161 may vertically overlap the second lens holder 153 . The first stopper 161 is disposed between the second lens holder 153 and the substrate 195 , and when the second lens holder 153 is moved toward the image sensor 190 , the movement is restricted. .

The second stopper 162 protrudes from below the upper portion 152 of the first lens holder 150 toward the substrate 195 , and protrudes below or equal to the upper surface of the first lens group 110 . can be The second stopper 162 may vertically overlap the second lens holder 153 . The second stopper 162 is disposed between the second lens holder 153 and the upper portion 152 of the first lens holder 150 , and the second lens holder 153 holds the first lens group 110 . As you move towards it, you limit your movement.

Here, when the total refractive power of the second lens group 120 has a positive refractive power, when an object to be focused moves from a long distance to a short distance, the second lens group 120 may move toward the object. Conversely, when the total refractive power of the second lens group 120 has a negative refractive power, when an object to be focused moves from a long distance to a short distance, the second lens group 120 moves toward the image sensor 190 . can Accordingly, the height of the camera module may be performed while maintaining the height of the object infinity. The second lens group 120 may be moved along the optical axis in a range of 2 mm or less, for example, 0.05 mm to 1 mm.

4 is a diagram illustrating an example of a lens optical system in a camera module according to an embodiment of the present invention.

Referring to FIG. 4 , in the camera module, the first lens group 210 may include at least two lenses, and the second lens group 220 may include three or four or more lenses. The stop ST may be disposed on the image side surface or the water side surface of any one of the first and second lenses 211 and 212 of the first lens group 210 . The diaphragm is disposed around the surface of the lens close to the first lens 211 in the first lens group 210 to control the amount of light. In the camera module, the first to sixth lenses 211, 212, 221, 222, 223, 224 may be made of a plastic material, and the plastic lens may have a higher refractive index than a glass material and may be provided as an aspherical surface, so that it is easy to control the path of the incident light. can

The first lens 211 may have positive (+) refractive power. The first lens 211 may include a plastic material. The second lens 111 may include a first surface S21 defined as an object-side surface and a second surface S22 defined as an image-side surface. The first surface S21 may be convex and the second surface S22 may be convex. At least one or both of the first surface S21 and the second surface S22 may be aspherical.

The effective radius of the first lens 211 may be greater than the effective radius of the second to fourth lenses 212 , 221 , and 223 with respect to the optical axis. Accordingly, the amount of ambient light may be improved.

The second lens 212 may have positive (+) or negative (-) refractive power. The second lens 212 may include a plastic material. The second lens 212 may include a third surface S23 defined as an object-side surface and a fourth surface S24 defined as an image-side surface. The third surface S23 may be an incident surface, and the fourth surface S24 may be an exit surface. The third surface S23 may be concave upward and the fourth surface S24 may be concave toward the water side. At least one or both of the third surface S23 and the fourth surface S24 may be aspherical.

The third lens 221 may have positive (+) or negative (-) refractive power. The third lens 221 may include a plastic material. The third lens 221 may include a fifth surface S25 defined as an object-side surface and a sixth surface S26 defined as an image-side surface. The fifth surface S25 may be convex toward the water side and the sixth surface S26 may be concave toward the water side. At least one of the fifth surface S25 and the sixth surface S26 may be a spherical surface or an aspherical surface. For example, both the fifth surface S25 and the sixth surface S26 may be aspherical.

The fourth lens 222 may have positive (+) or negative (-) refractive power. The fourth lens 222 may include a plastic material. The fourth lens 222 may include a seventh surface S27 defined as an object-side surface and an eighth surface S28 defined as an image-side surface. The seventh surface S27 may be convex toward the water side, and the eighth surface S28 may be convex upward. At least one of the seventh surface S27 and the eighth surface S28 may have an inflection point around the center. Both of the seventh and eighth surfaces S27 and S28 may be aspherical.

The fifth lens 223 may have positive (+) or negative (-) refractive power. The fourth lens 223 may include a plastic material. The fifth lens 223 may include a ninth surface S29 defined as an object-side surface and a tenth surface S30 defined as an image-side surface. The ninth surface S29 may be convex toward the water side, and the tenth surface S30 may be convex or concave. At least one of the ninth surface S29 and the tenth surface S30 may have an inflection point around the center. At least one or both of the seventh and eighth surfaces S29 and S30 may be aspherical.

The sixth lens 224 may have negative (-) refractive power. For example, the sixth lens 224 may include a plastic material. The fifth lens 224 may include an eleventh surface S31 defined as an object-side surface and a twelfth surface S32 defined as an image-side surface. The eleventh surface S31 may be concave upward and the twelfth surface S32 may be concave toward the object. That is, the eleventh surface S31 may have a shape in which a center region is concave upward, and a region around the center has a convex shape toward the object. The twelfth surface S32 may have a center region concave toward the object, a region around the center convex toward the sensor, and an edge region concave toward the object. The eleventh surface S31 of the sixth lens 224 may include an aspherical surface, and may include at least one or a plurality of inflection points. The twelfth surface S32 may include an aspherical surface, and may include at least one or a plurality of inflection points.

The filter 192 may include at least one of an infrared filter and an optical filter such as a cover glass. The filter 192 may pass light of a set wavelength band and filter light of a different wavelength band. When the filter 192 includes an infrared filter, radiant heat emitted from external light may be blocked from being transmitted to the image sensor. In addition, the filter 192 may transmit visible light and reflect infrared light.

According to the embodiment of the present invention, the first lens group 110 and 210 having at least one lens close to the object side are not moved, and the second lens group 120 and 220 disposed between the first lens group 110 and 210 and the image sensor 190 . By moving the second lens holder 153 having , in the optical axis direction, it is possible to focus by moving only the inner lens without moving the entire lens. Accordingly, even if the diagonal length of the image sensor 190 is increased, the focus may be adjusted using the second lens groups 120 and 220 without increasing the overall module size.

5 is a graph for explaining the module size in the AF stroke according to the diagonal length of the image sensor in the camera module, and FIG. 6 is the lens module and the lens module according to the increase in the diagonal size of the image sensor in the camera module according to an embodiment of the present invention. A diagram comparing the sizes of two lens groups.

5 , looking at the AF size based on the diagonal length of the image sensor, it can be seen that as the diagonal length of the image sensor increases, the module size for the AF stroke also increases proportionally. That is, since the movement distance for AF increases, the space or size of the module for AF stroke increases as the diagonal length of the image sensor increases. In the present invention, only some lenses in the camera module are moved, for example, the second lens group 120 is moved, so that it is not necessary to move the entire lens, and the size of the camera module may not increase as much as the diagonal length increases. there is.

6 , when the diagonal length of the image sensor increases, the size of the lens module also increases. In this case, the size of the second lens group may not increase by the increase in the size of the lens module even if the diagonal length of the image sensor increases . Accordingly, there is an effect of reducing the space required for the camera module or the overall length.

7 , a camera module 711 having a lens module according to an embodiment may be coupled to a case 700 of a mobile terminal. In the camera module 711 , a plurality of lens modules 712 , 732 , and 752 are arranged in one direction, and at least one or all of the lens modules may be vertically upward or downward. As another example, the plurality of lens modules 712 , 732 , and 752 may be arranged horizontally and/or vertically. A ToF lens module 772 may be added or a camera flash module may be further disposed within the camera module 711 , but the present disclosure is not limited thereto. A part of the lens module may protrude from the case 701 of the terminal.

Features, structures, effects, etc. described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, features, structures, effects, etc. illustrated in each embodiment can be combined or modified for other embodiments by those of ordinary skill in the art to which the embodiments belong. Accordingly, the contents related to such combinations and modifications should be interpreted as being included in the scope of the present invention.

In addition, although the embodiment has been described above, it is only an example and does not limit the present invention, and those of ordinary skill in the art to which the present invention pertains are exemplified above in a range that does not depart from the essential characteristics of the present embodiment. It can be seen that various modifications and applications that have not been made are possible. For example, each component specifically shown in the embodiment can be implemented by modification. And differences related to such modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

110,210: first lens group 111,211: first lens
121,211: second lens 212,221: third lens
213,222: fourth lens 214,223: fifth lens
215,224: sixth lens 120,220: second lens group
190: image sensor

Claims (10)

Board;
an image sensor disposed on the substrate;
a first lens group including at least one lens on the image sensor;
a second lens group including a plurality of lenses between the first lens group and the image sensor;
a first lens holder supporting the first lens group;
a second lens holder supporting the second lens group in the first lens holder; and
A camera module comprising a driving unit for moving the second lens holder in an optical axis direction. According to claim 1,
Each of the stoppers for limiting the movement of the second lens holder on the upper and lower portions of the first lens holder, the camera module comprising. 3. The method of claim 2,
Each of the stoppers vertically overlaps the second lens holder, the camera module. According to claim 1,
The driving unit includes a movable member disposed outside the second lens holder and an actuator having a fixing part facing the movable member inside the first lens holder. According to claim 1,
The first lens group includes three or less lenses,
The second lens group includes 2 to 5 lenses, the camera module. According to claim 1,
The total refractive power of the second lens group has a negative refractive power, the camera module. According to claim 1,
TTL in the camera module is in the range of 4mm to 10mm,
The effective focal length is in the range of 3mm to 10mm,
The amount of movement of the second lens group is in the range of 0.05mm to 1mm, the camera module. 8. The method according to any one of claims 1 to 7,
The first lens group includes a first lens,
The second lens group includes second to sixth lenses aligned from the object side to the image side,
The refractive index of the first lens is higher than that of the second to sixth lenses, the camera module. 9. The method of claim 8,
The Abbe numbers of the second and sixth lenses are lower than the Abbe numbers of the first, 3, 4, and 5 lenses,
The Abbe's number of the third, fourth, and fifth lenses is 50 or more, a camera module. 10. The method of claim 9,
The first lens has a positive refractive power,
The sixth lens has a negative refractive power, the camera module.

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