Optical system and camera module

Abstract

An optical system according to an embodiment of the present invention comprises first and second lens groups disposed along an optical axis, wherein the first lens group has positive (+) refractive power, the second lens group has negative (-) refractive power, and the lens disposed closest to an object side in the first lens group has the largest effective diameter.

Description

Optical system and camera module

[0001] The present invention relates to an optical system for enhanced optical performance and a camera module including the same.

[0002] Camera modules perform the function of capturing objects and saving them as images or videos, and are installed in various applications. In particular, camera modules are manufactured in ultra-compact sizes and are applied not only to portable devices such as smartphones, tablet PCs, and laptops, but also to drones and vehicles, providing a wide range of functions.

[0003] For example, the optical system of a camera module may include an imaging lens that forms an image and an image sensor that converts the formed image into an electrical signal. In this case, the camera module can perform an autofocus (AF) function that aligns the focal length of the lens by automatically adjusting the distance between the image sensor and the imaging lens, and can perform a zooming function of zooming up or zooming out by increasing or decreasing the magnification of a distant object through a zoom lens. Additionally, the camera module employs image stabilization (IS) technology to correct or prevent image shaking caused by camera movement resulting from unstable fixed devices or user movements.

[0004] The most important element for such camera modules to obtain an image is the imaging lens that forms the image. Recently, there has been growing interest in high performance, such as high image quality and high resolution, and research is being conducted on optical systems containing multiple lenses to achieve this.

[0005] For example, research is being conducted using multiple imaging lenses with positive (+) or negative (-) refractive power to implement a high-performance optical system. An optical system containing multiple lenses may have a set Effective Focal Length (EFL). In this case, when the value of the Effective Focal Length (EFL) is relatively large, the lens adjacent to the object side has a large aperture or the largest aperture among the multiple lenses. Consequently, since the lens closest to the object side has a relatively large size, there is a problem in that it is difficult to miniaturize the optical system.

[0006] An optical system containing multiple lenses may have a relatively large height. For example, as the number of lenses increases, the distance from the image sensor to the object surface of the lens adjacent to the object may increase. Accordingly, the overall thickness of a device such as a mobile device like a smartphone in which the optical system is placed may increase, and there is a problem that it is difficult to miniaturize.

[0007]

[0008] Camera modules for close-range imaging have a shorter TTL compared to conventional camera modules. As another example, camera modules for long-range imaging have a longer TTL compared to conventional camera modules. However, since portable terminals have limited installation space for camera modules, it is difficult to mount camera modules for long-range imaging or camera modules capable of image magnification adjustment (zoom camera modules). Therefore, a new optical system capable of solving the aforementioned problems is required.

[0009] The present embodiment aims to provide an optical system and a camera module with improved optical characteristics.

[0010] In addition, it is possible to provide an optical system that can be implemented in a small and compact manner.

[0011] Additionally, an optical system can be provided in which the lengths of the first direction and the second direction of at least one lens among the plurality of lenses that is adjacent to the object side or adjacent to the outside of the terminal are different. That is, an optical system can be provided in which at least one or two or more of the lenses have different lengths in two mutually orthogonal axis directions.

[0012] In addition, we aim to provide an optical system applicable to a folded camera or macro mode having a thin thickness or height.

[0013] To solve the above technical problem, an optical system according to an embodiment of the present invention includes first and second lens groups arranged along an optical axis, wherein the first lens group has a positive (+) refractive power and the second lens group has a negative (-) refractive power, and the effective diameter of the lens placed closest to the object side in the first lens group is the largest.

[0014] The object side of the lens positioned closest to the object side in the first lens group at the above optical axis may have a convex shape.

[0015] It may include a first light path control member disposed on the object side of the first lens group and a second light path control member disposed on the sensor side of the second lens group.

[0016] The above first lens group may include a first lens having a positive (+) refractive power, a second lens having a positive (+) refractive power, and a third lens having a negative (-) refractive power.

[0017] The above second lens group may include a fourth lens having a positive (+) refractive power, a fifth lens having a negative (-) refractive power, and a sixth lens having a positive (+) refractive power.

[0018] In the above optical axis, the second lens and the third lens may have a meniscus shape that is convex toward the sensor side.

[0019] In the above optical axis, the fourth lens has a shape with both sides convex, and in the above optical axis, the fifth lens may have a meniscus shape that is convex toward the sensor side.

[0020] The following condition can be satisfied. <Condition> 0.5 < TD_LG1 / TD_LG2 < 1.5

[0021] (In the above conditional equation, TD_LG1 is the length of the first lens group in the optical axis direction, and TD_LG2 is the length of the second lens group in the optical axis direction.)

[0022] The following condition can be satisfied. <Condition> 1 < TTL / ImgH < 2 (In the above condition, TTL is the optical axis distance from the vertex of the object side of the first lens to the top plane of the image sensor, and ImgH is the maximum diagonal length of the image sensor.)

[0023] To solve the above technical problem, an optical system according to an embodiment of the present invention includes first to sixth lenses arranged along an optical axis, wherein the first lens has a positive (+) refractive power, the second lens has a positive (+) refractive power, the third lens has a negative (-) refractive power, the fourth lens has a positive (+) refractive power, the fifth lens has a negative (-) refractive power, and the sixth lens has a negative (-) refractive power, wherein the thickness of the third lens among the first to sixth lenses is the smallest along the optical axis, and the first lens may have a meniscus shape that is convex toward the object side along the optical axis.

[0024] The first to third lenses above may be a first lens group having positive (+) refractive power, and the fourth to sixth lenses may be a second lens group having negative (-) refractive power.

[0025] Among the first to sixth lenses, the effective diameter of the first lens may be the largest, and among the first to sixth lenses, the effective diameter of the fourth lens may be the smallest.

[0026] In the above optical axis, the second lens and the third lens may have a meniscus shape that is convex toward the sensor side.

[0027] The following conditional equation may be satisfied. <Conditional Equation> 0.1 < ΣCT / TTL < 1 (In the above conditional equation, TTL is the optical axis distance from the vertex of the object side of the first lens to the top plane of the image sensor, and ΣCT is the sum of the thicknesses of the first to sixth lenses along the optical axis.)

[0028] The following condition can be satisfied. <Condition> 10 < TTL < 20 (In the above condition, TTL is the optical axis distance from the vertex of the object side of the first lens to the top plane of the image sensor.)

[0029] The optical system and camera module according to the present embodiment have various magnifications and can have excellent optical characteristics when providing various magnifications. Specifically, the embodiment can have various magnifications by controlling a lens group having a set number of lenses and refractive power, a plurality of lenses having a set shape and focal length, and a moving distance of a moving lens group, and can provide an autofocus (AF) function for the subject.

[0030] In addition, each of the multiple lens groups can correct aberration characteristics or mutually complement aberration characteristics that change due to movement. Accordingly, the optical system according to the embodiment can minimize or prevent changes in chromatic aberration and aberration characteristics that occur when the magnification changes.

[0031] In addition, the effective focal length (EFL) can be controlled by moving only some of the lens groups among multiple lens groups, and the moving distance of the moving lens groups can be minimized. Accordingly, the embodiment can significantly reduce the moving distance of the lens groups when changing the magnification and minimize the power consumption required when moving the lens groups.

[0032] In addition, the optical system according to the present embodiment has enhanced optical characteristics and can have a large BFL (Back focal length), thereby providing an optical system suitable for a folded camera module.

[0033] FIG. 1 is a diagram showing the configuration of an optical system according to the first embodiment of the present invention operating in a first mode.

[0034] FIG. 2 is a configuration diagram of an optical system according to the first embodiment of the present invention operating in a second mode.

[0035] FIG. 3 is a table showing the aspherical coefficients of the lenses in the optical system according to the first embodiment.

[0036] FIG. 4 is a graph showing data for the diffraction MTF (Modulation Transfer Function) of the optical system according to the first embodiment of the present invention operating in the first mode.

[0037] FIG. 5 is a graph showing data on the diffraction MTF of the optical system according to the first embodiment of the present invention operating in the first mode.

[0038] FIG. 6 is a graph showing data on the aberration characteristics of the optical system according to the first embodiment of the present invention operating in the first mode.

[0039] FIG. 7 is a graph showing data on the aberration characteristics of the optical system according to the first embodiment operating in the second mode.

[0040] FIG. 8 is a graph showing the relative illumination ratio (Relative Illumination Versus Relative Field) of the optical system according to the first embodiment of the present invention operating in the first mode.

[0041] FIG. 9 is a graph showing the ambient light ratio of the optical system according to the first embodiment of the present invention operating in a second mode.

[0042] FIG. 10 is a configuration diagram of an optical system according to the second embodiment of the present invention operating in a first mode.

[0043] FIG. 11 is a diagram showing the configuration of an optical system according to the second embodiment of the present invention operating in a second mode.

[0044] FIG. 12 is a table showing the aspherical coefficients of lenses in an optical system according to the second embodiment.

[0045] FIG. 13 is a graph showing data for the diffraction MTF of the optical system according to the second embodiment of the present invention operating in the first mode.

[0046] FIG. 14 is a graph showing data for the diffraction MTF of the optical system according to the second embodiment of the present invention operating in the first mode.

[0047] FIG. 15 is a graph showing data on the aberration characteristics of the optical system according to the second embodiment of the present invention operating in the first mode.

[0048] FIG. 16 is a graph showing data on the aberration characteristics of the optical system according to the second embodiment of the present invention operating in a second mode.

[0049] FIG. 17 is a graph showing the ambient light ratio of an optical system according to the second embodiment of the present invention operating in the first mode.

[0050] FIG. 18 is a graph showing the ambient light ratio of an optical system according to the second embodiment of the present invention operating in a second mode.

[0051] FIG. 19 is a drawing for explaining the D-cut lens of the present invention.

[0052] FIG. 20 is an example of a portable terminal having an optical system according to the present embodiment.

[0053] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0054] However, the technical concept of the present invention is not limited to the first and second embodiments described herein but can be implemented in various different forms, and within the scope of the technical concept of the present invention, one or more of the components of the first and second embodiments may be selectively combined or substituted.

[0055] In addition, terms used in the first and second embodiments (including technical and scientific terms) may be interpreted in a sense that is generally understood by those skilled in the art to which the first and second embodiments belong, unless explicitly and specifically defined otherwise. Terms that are commonly used, such as terms defined in advance, may be interpreted in consideration of their meaning in the context of the relevant technology.

[0056] Furthermore, the terms used in the first and second embodiments are intended to describe the first and second embodiments and are not intended to limit the invention.

[0057] In this specification, the singular form may include the plural form unless specifically stated otherwise in the text, and when described as "at least one of A and B and C (or more than one)," it may include one or more of all combinations that can be formed from A, B, and C.

[0058] In addition, terms such as first, second, A, B, (a), (b), etc., may be used when describing the components of the first and second embodiments. These terms are used merely to distinguish the components from other components and are not intended to limit the essence, order, or sequence of the components.

[0059] And, where it is stated that a component is 'connected', 'combined', or 'connected' to another component, this may include not only cases where the component is directly 'connected', 'combined', or 'connected' to the other component, but also cases where it is 'connected', 'combined', or 'connected' due to another component located between the component and the other component.

[0060] Furthermore, when described as being formed or placed "above" or "below" each component, "above" or "below" includes not only cases where two components are in direct contact with each other, but also cases where one or more other components are formed or placed between the two components. Additionally, when expressed as "above" or "below," it may include the meaning of a downward direction as well as an upward direction relative to a single component.

[0061] In the description of the invention, "object side" may refer to a surface of the lens facing the object side with respect to the optical axis (OA), and "sensor side" may refer to a surface of the lens facing the imaging surface (image sensor) with respect to the optical axis. "Object side" may be the "object side," and "sensor side" may be the "image side." One surface of the lens being convex may refer to a convex shape in the optical axis or paraxial region, and one surface of the lens being concave may refer to a concave shape in the optical axis or paraxial region. The radius of curvature, center thickness, and optical axis spacing between lenses listed in the lens data table may refer to values ​​(unit, mm) in the optical axis. The vertical direction may refer to a direction perpendicular to the optical axis, and the end of the lens or lens surface may refer to the end of the effective area of ​​the lens through which incident light passes. The size of the effective diameter of the lens surface may have a measurement error of up to ±0.4 mm depending on the measurement method, etc. The above paraxial region refers to a very narrow region near the optical axis, and is a region where the distance of light rays from the optical axis (OA) is almost zero. Hereinafter, the term optical axis may include the center of each lens or a very narrow region near the optical axis.

[0062] The optical axis (OA) may refer to the central axis on the path of light that is bent from the second direction (Y-axis direction) by the first optical path control member (111) to the first direction (X-axis direction) and bent from the first direction (X-axis direction) to the second direction (Y-axis direction) by the first optical path control member (112).

[0063]

[0064] The optical system (1000, 1100) according to the first and second embodiments may include a plurality of lens groups. Specifically, the optical system (1000, 1100) may include a plurality of lens groups, each including at least one lens. For example, the optical system (1000, 1100) may include a first light path control member (111, 211), a first lens group (LG1), a second lens group (LG2), a second light path control member (112, 212), and an image sensor (300) arranged sequentially from the object side toward the image sensor.

[0065] The first and second lens groups (LG1, LG2) may each have a positive (+) or negative (-) refractive power. The first lens group (LG1) and the second lens group (LG2) may have refractive powers of different signs. For example, the first lens group (LG1) may have a positive (+) refractive power, and the second lens group (LG2) may have a negative (-) refractive power.

[0066] At least one of the first lens group (LG1) and the second lens group (LG2) may be provided to be movable in the direction of the optical axis (OA). For example, in the first embodiment, the first lens group (LG1) may be provided to be movable in the direction of the optical axis (OA), and the second lens group (LG2) may be fixed. Additionally, in the second embodiment, the first lens group (LG1) may be fixed, and the second lens group (LG2) may be provided to be movable in the direction of the optical axis (OA).

[0067]

[0068] A first light path control member (111, 211) may be disposed on the object side of the first lens group (LG1). By including the first light path control member (111, 211), the optical system (1000, 1100) can reduce the thickness of the optical system (1000, 1100) in the first direction (X-axis direction) and the second direction (Y-axis direction). If the optical system (1000, 1100) does not include the first light path control member (111, 211), a plurality of lenses within the optical device including the optical system (1000, 1100) may be disposed extending in a direction perpendicular to the surface of the optical device.

[0069] Accordingly, multiple lenses have a high height in a direction perpendicular to the surface of the optical device, and it may be difficult to form the thickness of the optical device into an ultra-thin shape. A prism lens can change light incident in a direction perpendicular to the plane of the optical device into a direction parallel to the surface of the optical device. That is, multiple lenses included in the optical system (1000, 1100) can be arranged to extend in a direction parallel to the surface of the optical device, and the optical device can be formed with a thin thickness.

[0070]

[0071] The first lens group (LG1) may include a plurality of lenses. Specifically, the first lens group (LG1) may include three or more lenses having opposite refractive powers. The number of lenses included in the first lens group (LG1) may be equal to the number of lenses included in the second lens group (LG2). For example, the first lens group (LG1) may include three lenses.

[0072] A plurality of lenses included in the first lens group (LG1) may have a set spacing. Specifically, the spacing between the plurality of lenses included in the first lens group (LG1) may remain constant and not change in the operation mode described later. For example, the spacing between the first lens (101, 201) and the second lens (102, 202), and the spacing between the second lens (102, 202) and the third lens (103, 203) may remain constant and not change according to the operation mode described later.

[0073] The second lens group (LG2) may include multiple lenses. Specifically, the second lens group (LG2) may include three or more lenses having opposite refractive powers. The number of lenses included in the second lens group (LG2) may be equal to the number of lenses included in the first lens group (LG1). For example, the second lens group (LG2) may include three lenses.

[0074] Multiple lenses included in the second lens group (LG2) may have set spacing. Specifically, the spacing between multiple lenses included in the second lens group (LG2) may remain constant and not change in the operation mode described later. For example, the spacing between the fourth lens (104, 204) and the fifth lens (105, 205), and the spacing between the fifth lens (105, 205) and the sixth lens (106, 206) may remain constant and not change according to the operation mode described later.

[0075]

[0076] A second optical path control member (112, 212) may be disposed on the sensor side of the second lens group (LG2). The optical system (1000, 1100) may reduce the thickness of the optical system (1000, 1100) in the first direction (X-axis direction) and the second direction (Y-axis direction) by including the first optical path control member (112, 212). If the optical system (1000, 1100) does not include the first optical path control member (112, 212), a plurality of lenses within the optical device including the optical system (1000, 1100) may be disposed extending in a direction perpendicular to the surface of the optical device.

[0077] Accordingly, multiple lenses have a high height in a direction perpendicular to the surface of the optical device, and it may be difficult to form the thickness of the optical device into an ultra-thin shape. A prism lens can change light incident in a direction perpendicular to the plane of the optical device into a direction parallel to the surface of the optical device. That is, multiple lenses included in the optical system (1000, 1100) can be arranged to extend in a direction parallel to the surface of the optical device, and the optical device can be formed with a thin thickness.

[0078]

[0079] A driving member (not shown) may be connected to an optical path control member. The driving member may include at least one actuator. For example, the driving member may include at least one of a VCM (Voice Coil Motor), a piezo-electric device, a shape memory alloy, or a MEMS device as the actuator. The driving member may move the optical path control member using the driving force of the actuator. For example, the driving member may tilt the optical path control member along a first axis (X-axis) or a second axis (Y-axis). Accordingly, the camera module (1520) can correct shaking.

[0080] It includes a detection unit (not shown) for detecting shaking of the camera module (1520), and the detection unit can detect rotation and position changes applied to the camera module (1520). The detection unit may include at least one of a sensor that detects changes in angular velocity, for example, a gyro sensor, and an acceleration sensor that detects changes in acceleration.

[0081] The camera module (1520) can control the movement of the optical path control member by means of a control signal. Specifically, if shaking occurs in the camera module (1520), information regarding the shaking, such as the degree of rotation and position change of the sensors, can be detected, and correction for the shaking can be performed.

[0082] Accordingly, the camera module (1520) according to the embodiment can effectively correct shaking caused by rotation and shaking caused by changes in position when photographing a subject located at infinity or macro distance. Therefore, the camera module (1520) can have improved optical characteristics.

[0083]

[0084] The optical system (1000, 1100) may include a first light path control member (111, 211), a plurality of lens groups (LG1, LG2), a second light path control member (112, 212), and an image sensor (300) arranged sequentially from the object side toward the sensor. Additionally, the optical system (1000, 1100) may include a plurality of lenses included in the lens groups (LG1, LG2), for example, a first lens (101, 201), a second lens (102, 202), a third lens (103, 203), a fourth lens (104, 204), a fifth lens (105, 205), and a sixth lens (106, 206).

[0085] The first lens group (LG1) may include a first lens (101, 201), a second lens (102, 202), and a third lens (103, 203). The second lens group (LG2) may include a fourth lens (104, 204), a fifth lens (105, 205), and a sixth lens (106, 206). The first to sixth lenses (101 to 106) and the image sensor (300) may be arranged sequentially along the optical axis (OA) of the optical system (1000, 1100).

[0086] Each of the plurality of lenses (100) may include an effective region and a non-effective region. The effective region may be a region through which light incident on each of the first to sixth lenses (101 to 106) passes. That is, the effective region may be a region where the incident light is refracted to realize optical characteristics.

[0087] The non-effective region may be positioned around the perimeter of the effective region. The non-effective region may be an area where light is not incident. In other words, the non-effective region may be an area unrelated to optical properties. Additionally, the non-effective region may be an area fixed to a barrel (not shown) that accommodates the lens.

[0088] Referring to FIG. 19, at least one of the first to sixth lenses (101 to 106) in the optical system (1000, 1100) according to the first and second embodiments may have a D-cut technique applied. When the D-cut technique is applied, the height of the entire optical system may be reduced by cutting off a portion of the lens effective diameter or rib. Here, the height of the entire optical system may refer to the length in a direction perpendicular to the optical axis, rather than the TTL. The D-cut lens may have a non-circular shape, and the length (A) in the first direction (X-axis direction) and the length (B) in the second direction (Y-axis direction) may be different.

[0089]

[0090] The image sensor (300) can detect light. The image sensor (300) can detect light that has passed through a plurality of lenses, for example, the first to sixth lenses (101 to 106) in sequence. The image sensor (300) may include a Charge Coupled Device (CCD) or a Complementary Metal Oxide Semiconductor (CMOS), etc.

[0091] The optical system (1000, 1100) may further include a filter (400). The filter (400) may be placed between a plurality of lenses and an image sensor (300). The filter (400) may be placed between the image sensor (300) and the second lens group (LG2) that is closest to the image sensor (300) among a plurality of lens groups (LG1, LG2). For example, the filter (400) may be placed between the image sensor (300) and the sixth lens (106), which is the last lens of the second lens group (LG2) closest to the image sensor (300) among the plurality of lenses.

[0092] The filter (400) may include at least one of an optical filter, such as an infrared filter or a cover glass. The filter (400) may pass light of a set wavelength band and filter light of a different wavelength band. If the filter (400) includes an infrared filter, it may block radiant heat emitted from external light from being transmitted to the image sensor (300). Additionally, the filter (400) may transmit visible light and reflect infrared light.

[0093] The optical system (1000, 1100) may include an aperture (not shown). The aperture can control the amount of light incident on the optical system (1000, 1100). The aperture may be located in front of the first lens (101, 201) or positioned between two lenses selected from the first to sixth lenses (101 to 106).

[0094]

[0095] The optical system according to the first embodiment of the invention will be described.

[0096] FIG. 1 is a configuration diagram of an optical system according to the first embodiment of the present invention operating in a first mode, FIG. 2 is a configuration diagram of an optical system according to the first embodiment of the present invention operating in a second mode, FIG. 3 is a table showing the aspherical coefficients of lenses in the optical system according to the first embodiment of the present invention, FIG. 4 is a graph showing data on the diffraction MTF (Modulation Transfer Function) of the optical system according to the first embodiment of the present invention operating in a first mode, FIG. 5 is a graph showing data on the diffraction MTF of the optical system according to the first embodiment of the present invention operating in a first mode, FIG. 6 is a graph showing data on the aberration characteristics of the optical system according to the first embodiment of the present invention operating in a first mode, FIG. 7 is a graph showing data on the aberration characteristics of the optical system according to the first embodiment of the present invention operating in a second mode, and FIG. 8 shows the relative illumination ratio (Relative Illumination Versus Relative Field) of the optical system according to the first embodiment of the present invention operating in a first mode. FIG. 9 is a graph showing the ratio of ambient light to light of an optical system according to the first embodiment of the present invention operating in a second mode.

[0097] Referring to FIG. 1, the optical system (1000) includes a lens portion, and the lens portion may include first to sixth lenses (101 to 106). The first to sixth lenses (101 to 106) may be arranged sequentially along the optical axis (OA) of the optical system (1000). Light corresponding to information about an object may pass through the first to sixth lenses (101 to 106) and a filter (400) and be incident on an image sensor (300). The optical axis (OA) may refer to the central axis of light incident from the first lens (101) to the image sensor (300).

[0098]

[0099] The first light path control member (111) may be positioned on the object side of the first lens (101). The first light path control member (111) may include a plastic or glass material. The first light path control member (111) can change the path of light incident from the outside. The first light path control member (111) may include a mirror and a prism.

[0100] The first light path control member (111) can rotate the light path by 90°. The first light path control member (111) includes an incident surface (P1) into which light is incident, a reflective surface (RS1) that reflects the incident light, and an exit surface (P2) that emits the reflected light. The reflective surface (RS1) has an inclination angle of 45° and reflects the main beam of the incident light by 90°, thereby serving to reflect the incident light to the first lens (101). The first light path control member (111) can change the light path to the first direction (X-axis direction) by reflecting the light incident in the second direction (Y-axis direction).

[0101] In addition, to reduce the length in the direction of the first axis (Y-axis) of the optical system, the angle formed by the reflective surface (RS1) and the outgoing surface (P2) in the first optical path control member (111) can be changed from about 45 degrees to about 43 degrees or about 47 degrees. The angle formed by the reflective surface (RS1) and the outgoing surface (P2) in the first optical path control member (111) can be changed to be greater or smaller than about 45 degrees depending on the position where the image sensor is placed.

[0102] For example, if the direction of light incident from the object side of the first light path control member (111) and the direction of light incident on the image sensor are the same direction, the angle formed by the reflective surface (RS1) and the exit surface (P2) in the first light path control member (111) can be changed to approximately 43 degrees. If the direction of light incident on the lens placed on the object side of the first light path control member (111) and the direction of light incident on the image sensor are opposite directions, the angle formed by the reflective surface (RS1) and the exit surface (P2) in the first light path control member (111) can be changed to approximately 47 degrees. Through this, the size of the optical system can be reduced within a range where the change in optical system performance is minimal.

[0103]

[0104] The first lens (101) may be positioned closest to the object side. The first lens (101) may be positioned furthest from the sensor side. The first lens (101) may have a positive (+) refractive power at the optical axis (OA). The first lens (101) may include plastic or glass material. For example, the first lens (101) may be provided with plastic material.

[0105] With respect to the optical axis (OA), the first surface (S1) on the object side of the first lens (101) may be convex, and the second surface (S2) on the sensor side may be concave. The first lens (101) may have a meniscus shape that is convex toward the object side. The first lens (101) may have a meniscus shape that is concave toward the sensor side. The first lens (101) may have an aspherical surface. The aspherical coefficients of the first surface (S1) and the second surface (S2) of the first lens (101) may be provided as L1S1 and L1S2 of FIG. 3. At least one or both of the first surface (S1) and the second surface (S2) of the first lens (101) may be provided without a critical point from the optical axis to the end of the effective area.

[0106]

[0107] The second lens (102) may be positioned second from the object side. The second lens (102) may be positioned fifth from the sensor side. The second lens (102) may be positioned between the first lens (101) and the third lens (103). The second lens (102) may have a positive (+) refractive power. The second lens (102) may include plastic or glass material. For example, the second lens (102) may be provided with plastic material.

[0108] With respect to the optical axis, the object-side third surface (S3) of the second lens (102) may be concave, and the sensor-side fourth surface (S4) may be convex. The second lens (102) may have a meniscus shape in which the object-side is concave at the optical axis (OA). The second lens (102) may have a meniscus shape in which the sensor-side is convex at the optical axis (OA). The second lens (102) may be made of plastic material and may have an aspherical surface. The aspherical coefficients of the third surface (S3) and the fourth surface (S4) may be provided as L2S1 and L2S2 of FIG. 3. At least one or both of the third surface (S3) and the fourth surface (S4) of the second lens (102) may be provided without a critical point from the optical axis to the end of the effective area.

[0109]

[0110] The third lens (103) may be positioned as the third lens from the object side. The third lens (103) may be positioned as the fourth lens from the sensor side. The third lens (103) may be positioned between the second lens (102) and the fourth lens (104). The third lens (103) may have a negative (-) refractive power at the optical axis (OA). The third lens (103) may include plastic or glass material. For example, the third lens (103) may be provided with plastic material.

[0111] With respect to the optical axis, the object-side fifth surface (S5) of the third lens (103) may be concave, and the sensor-side sixth surface (S6) may be convex. The third lens (103) may have a meniscus shape with the object side being concave. The third lens (103) may have a meniscus shape with the sensor side being convex. The third lens (103) may be made of plastic material and may have an aspherical surface. The aspherical coefficients of the fifth surface (S5) and the sixth surface (S6) may be provided as L3S1 and L3S2 of FIG. 3. At least one or both of the fifth surface (S5) and the sixth surface (S6) of the third lens (103) may be provided without a critical point from the optical axis to the end of the effective area.

[0112]

[0113] The fourth lens (104) may be positioned as the fourth lens from the object side. The fourth lens (104) may be positioned as the third lens from the sensor side. The fourth lens (104) may be positioned between the third lens (103) and the fifth lens (105). The fourth lens (104) may have a positive (+) refractive power. The fourth lens (104) may include plastic or glass material. For example, the fourth lens (104) may be provided with plastic material.

[0114] With respect to the optical axis, the object-side 7th surface (S7) of the 4th lens (104) may be convex, and the sensor-side 8th surface (S8) may be convex. The 4th lens (104) may have a shape with both sides convex. The 4th lens (104) may be made of plastic material and may have an aspherical surface. The aspherical coefficients of the 7th surface (S7) and the 8th surface (S8) may be provided as L4S1 and L4S2 of FIG. 3. At least one or both of the 7th surface (S7) and the 8th surface (S8) of the 4th lens (104) may be provided without a threshold point from the optical axis to the end of the effective area.

[0115]

[0116] The fifth lens (105) may be positioned as the fifth lens from the object side. The fifth lens (105) may be positioned as the second lens from the sensor side. The fifth lens (105) may be positioned between the fourth lens (104) and the sixth lens (106). The fifth lens (105) may have a negative (-) refractive power. The fifth lens (105) may include plastic or glass materials. For example, the fifth lens (105) may be provided with a plastic material.

[0117] With respect to the optical axis (OA), the 5th lens (105) may have a concave 9th surface (S9) on the object side and a convex 10th surface (S10) on the sensor side. The 5th lens (105) may have a meniscus shape that is concave on the object side at the optical axis (OA). The 5th lens (105) may have a meniscus shape that is convex on the sensor side at the optical axis (OA). The 5th lens (105) is made of plastic material and may have an aspherical surface. The aspherical coefficients of the 9th surface (S9) and the 10th surface (S10) may be provided as L5S1 and L5S2 of FIG. 3. At least one or both of the 9th surface (S9) and the 10th surface (S10) of the 5th lens (105) may be provided without a critical point from the optical axis to the end of the effective area.

[0118]

[0119] The sixth lens (106) may be positioned furthest from the object side. The sixth lens (106) may be positioned closest to the sensor side. The sixth lens (106) may have negative (-) refractive power. The sixth lens (106) may include plastic or glass material. For example, the sixth lens (106) may be provided with plastic material.

[0120] With respect to the optical axis (OA), the 6th lens (106) may have an object-side 11th surface (S11) that is concave and a sensor-side 12th surface (S12) that is concave. The 6th lens (106) may have a shape with both sides concave. The 6th lens (106) may be made of plastic material and may have an aspherical surface. The aspherical coefficients of the 11th surface (S11) and the 12th surface (S12) may be provided as L6S1 and L6S2 of FIG. 3. At least one or both of the 11th surface (S11) and the 12th surface (S12) of the 6th lens (106) may be provided without a threshold point from the optical axis to the end of the effective area.

[0121]

[0122] The second light path control member (112) may be positioned on the sensor side of the sixth lens (106). The second light path control member (112) may be positioned closest to the sensor side. The second light path control member (112) may be positioned furthest from the object side. The second light path control member (112) can change the path of light incident from the outside. The second light path control member (112) may include a reflector and a prism.

[0123] The second light path control member (112) can rotate the light path by 90°. The second light path control member (112) includes an incident surface (P3) where light is incident, a reflective surface (RS2) that reflects the incident light, and an output surface (P4) that emits the reflected light. The reflective surface (RS2) has an inclination angle of 45° and reflects the main beam of the incident light by 90°, thereby serving to reflect the incident light to the image sensor (300). The second light path control member (112) can change the light path to the second direction (Y-axis direction) by reflecting the light incident in the first direction (X-axis direction).

[0124]

[0125] LensSurfaceRadiusThicknessndvdClearApertureprism1P1infinity8.0001.72329.4993.700 P2infinityVariable(D1) 3.7001S15.2001.4881.53755.7303.050 S211.5061.119 2.8632S3-7504.4331.5001.53463.7632.716 S4-6.3900.100 2.6723S5-6.1991.3601.67321.7522.549 S6-13.511 Variable (D2) 2.3894S724.2791.5001.66822.2632.130 S8-24.4800.518 2.0715S9-12.5851.5001.53463.7632.294 S10-202.4351.000 2.2916S11-9.3421.4971.67321.7982.329 S1222.5650.400 2.978prism2P3infinity6.4001.65233.8423.197 P4infinity0.300 3.999filter 0.210 4.932air 0.300 4.989image 0.000 5.122

[0126] Table 1 shows the surface number, radius of curvature, thickness of the center of each lens or distance between lens surfaces, index, nd, Abbe number (Abbe,vd), clear aperture, and focal length of the lens according to the first embodiment of the present invention. At this time, the units of the radius of curvature and the thickness or distance may be mm.

[0127] In Table 1, the thickness of the first optical path control member (111) and the second optical path control member (112) may refer to the thickness along the optical axis (OA). For example, the thickness of the first optical path control member (111) may refer to the sum of the thickness from the incident surface (P1) to the reflection surface (RS1) along the y-axis and the thickness from the reflection surface (RS1) to the exit surface (P2) along the x-axis. The thickness of the first optical path control member (112) may refer to the sum of the thickness from the incident surface (P1) to the reflection surface (RS1) along the y-axis and the thickness from the reflection surface (RS2) to the exit surface (P4) along the x-axis.

[0128] Additionally, the thickness from the incident surface (P1) to the reflection surface (RS1) along the y-axis of the first light path control member (111) and the thickness from the reflection surface (RS1) to the exit surface (P2) along the x-axis of the first light path control member (111) may be the same. The thickness from the incident surface (P3) to the reflection surface (RS2) along the y-axis of the second light path control member (112) and the thickness from the reflection surface (RS2) to the exit surface (P4) along the x-axis of the second light path control member (112) may be the same.

[0129] According to a modified example, the thickness from the incident surface (P1) to the reflection surface (RS1) along the y-axis of the first light path control member (111) and the thickness from the reflection surface (RS1) to the exit surface (P2) along the x-axis of the first light path control member (111) may be different. The thickness from the incident surface (P3) to the reflection surface (RS2) along the y-axis of the second light path control member (112) and the thickness from the reflection surface (RS2) to the exit surface (P4) along the x-axis of the second light path control member (112) may be different.

[0130]

[0131] 1st Mode 2nd Mode D12.0000.208D20.5002.292

[0132] Table 2 shows the distance between lenses (D1, D2) that varies when operating in either the first mode or the second mode in the optical system according to the first embodiment of the present invention. Here, the first mode refers to the case of photographing an object located at infinity, and the second mode may refer to the case of photographing an object located at a macroscopic distance (e.g., within 100 mm).

[0133] In the optical system according to the first embodiment, the distance between adjacent lens groups may change during the process of changing from a first mode to a second mode. The first lens group (LG1) may move, and the second lens group (LG2) may be fixed. The first lens group (LG1) may be a moving group, and the second lens group (LG2) may be a fixed group.

[0134] When operating from the first mode to the second mode, the distance (D1) between the first light path control member (111) and the first lens group (LG1) may decrease, and the distance (D2) between the first lens group (LG1) and the second lens group (LG2) may increase. When operating from the second mode to the first mode, the distance (D1) between the first light path control member (111) and the first lens group (LG1) may increase, and the distance (D2) between the first lens group (LG1) and the second lens group (LG2) may decrease.

[0135] The stroke length of the first lens group (LG1) can be 1.5 mm to 2.0 mm, and preferably about 1.792 mm. As the first lens group (LG1) moves, the optical performance of the optical system (1000) may change.

[0136]

[0137] EFL(F)17.060Fno2.797BFL_17.610HFOV16.510BFL_27.610EPD6.100f116.319ET10.805f211.96 5ET21.095f3-18.394ET31.646f418.482ET41.284f5-25.176ET51.623f6-9.642ET61.983CA_Max 5.913L_CT_max1.500CA_Min4.200L_CT_min1.360CA_Aver5.055L_CT_aver1.474ΣCG2.737ΣCT8. 846TTL19.692LG1_stroke1.792f_LG112.595TD_LG15.567f_LG2-12.760TD_LG26.015ImgH10.244

[0138] Table 3 relates to the items of the mathematical formulas described above in the optical system (1000) of the first embodiment, including the effective focal length (EFL(F)(mm)) in the first mode of the optical system (1000), the distance from the sensor side of the last lens to the image sensor (BFL(mm)), the horizontal field of view (HFOV(degree)), the focal lengths (f1~f6)(mm) of the first to sixth lenses (101~106), the edge thickness (ET1~ET6), the length of each lens group in the optical axis direction (TD_LG1, TD_LG2), the focal lengths (f_LG1, f_LG2)(mm) of the first to second lens groups (LG1, LG2), the size of the entrance pupil (EPD(mm)), the optical axis distance (TD(mm)) from the first lens (101) to the sixth lens (106), the brightness (Fno) of the optical system (1000), and the stroke of the first lens group (LG1). This relates to the length (LG1_stroke), the total optical axis distance of the optical system (1000) TTL (mm), ImgH (mm), the maximum effective diameter (CA_Max), the minimum effective diameter (CA_Min), the average effective diameter (CA_Aver), the maximum center thickness (L_CT_max), the minimum center thickness (L_CT_min), the average center thickness (L_CT_aver), etc., among the first to sixth lenses (101~106).

[0139]

[0140] In the following, the center thickness of the first to sixth lenses (101 to 106) is denoted as CT1 to CT6, the edge thickness of the effective area of ​​each lens is denoted as ET1 to ET6, and the center gap between two adjacent lenses is denoted as CG1 to CG5. BFL (Back focal length) is the optical axis distance from the image sensor (300) to the center of the last lens. TTL is the optical axis distance from the center of the first surface (S1) of the first lens (101) to the top surface of the image sensor (300). In the following, the description of the relationship between the first optical path control member (111) and the second optical path control member (112) is partially omitted.

[0141]

[0142] When comparing the absolute values ​​of the radius of curvature of each lens, the radius of curvature of the third surface (S3) of the second lens (102) at the optical axis (OA) may be the maximum among the lenses, and the radius of curvature of the first surface (S1) of the first lens (101) may be the minimum among the lenses. The absolute value of the radius of curvature of the first surface (S1) of the first lens (101) may be smaller than the absolute value of the radius of curvature of the second surface (S2). The absolute value of the radius of curvature of the third surface (S3) of the second lens (102) may be larger than the absolute value of the radius of curvature of the fourth surface (S4). The absolute value of the radius of curvature of the fifth surface (S5) of the third lens (103) may be smaller than the absolute value of the radius of curvature of the sixth surface (S6). The absolute value of the radius of curvature of the 7th surface (S7) of the 4th lens (104) may be smaller than the absolute value of the radius of curvature of the 8th surface (S8). The absolute value of the radius of curvature of the 9th surface (S9) of the 5th lens (105) may be smaller than the absolute value of the radius of curvature of the 10th surface (S10). The absolute value of the radius of curvature of the 11th surface (S11) of the 6th lens (106) may be smaller than the absolute value of the radius of curvature of the 12th surface (S12).

[0143] The ratio of the radius of curvature of each lens can satisfy the following conditions.

[0144] Condition 1: 0.1 < |L1R1 / L1R2| < 0.5

[0145] Condition 2: 1000 < |L2R1 / L2R2| < 1200

[0146] Condition 3: 0.1 < |L3R1 / L3R2| < 0.5

[0147] Condition 4: 0.5 < |L4R1 / L4R2| < 1

[0148] Condition 5: 0.01 < |L5R1 / L5R2| < 0.1

[0149] Condition 6: 0.1 < |L6R1 / L6R2| < 0.5

[0150]

[0151] When describing the center thickness of the lenses based on the optical axis, the center thicknesses (CT2, CT4, CT5) of the second lens (102), the fourth lens (104), and the fifth lens (105) are the largest among the lenses, and the center thickness (CT3) of the third lens (103) is the smallest among the lenses. The difference between the maximum center thickness and the minimum center thickness among the lenses may be in the range of 0.1 mm or more and 0.3 mm or less.

[0152] The center thickness of each lens can satisfy any one of the following conditions.

[0153] Condition 1: CT2, CT4, CT5, CT6 > CT1 > CT3

[0154] Condition 2: CT2 = CT4 = CT5 > CT1, CT3, CT6

[0155] Condition 3: CT1, CT2, CT4, CT5, CT6 > CT3

[0156] Condition 4: CT2, CT4, CT5 > CT6 > CT1, CT3

[0157]

[0158] When zooming, the gap (CG1) between the first lens (101) and the second lens (102), the gap (CG2) between the second lens (102) and the third lens (103), the gap (CG4) between the fourth lens (104) and the fifth lens (105), and the gap (CG5) between the fifth lens (105) and the sixth lens (106) do not change, while the gap (CG3) between the third lens (103) and the fourth lens (104) may change. Among the center gaps between the lenses that do not change, the gap (CG1) between the first lens (101) and the second lens (102) may be maximum, and the gap (CG2) between the second lens (102) and the third lens (103) may be minimum. Among the gaps between the lenses, the difference between the maximum center gap and the minimum center gap may be 1.0 mm or more, for example, in the range of 1.0 mm to 1.5 mm.

[0159] The center spacing between each lens can satisfy the following conditions.

[0160] Condition 1: CG1 > CG2, CG4, CG5

[0161] Condition 2: CG1, CG4, CG5 > CG2

[0162] Condition 3: CG1, CG5 > CG4 > CG2

[0163] Condition 4: CG1 > CG5 > CG2, CG4

[0164]

[0165] Regarding the effective aperture, the lens having the maximum effective aperture may be the first lens (101). Here, the effective aperture is the average of the effective aperture on the object side and the effective aperture on the sensor side of each lens. The lens surface having the maximum effective aperture may be the first surface (S1) of the first lens (101). The lens having the minimum effective aperture may be the fourth lens (104). The lens surface having the minimum effective aperture may be the eighth surface (S8) of the fourth lens (104). The effective apertures of the first to sixth lenses (101-106) may be larger than the diagonal length of the image sensor (300).

[0166] The effective diameter of each lens can satisfy any one of the following conditions.

[0167] Condition 1: CA_L1 > CA_L2, CA_L3, CA_L4, CA_L5, CA_L6

[0168] Condition 2: CA_L1 > CA_L2 > CA_L3, CA_L4, CA_L5, CA_L6

[0169] Condition 3: CA_L1, CA_L2, CA_L6 > CA_L3 > CA_L4, CA_L5

[0170] Condition 4: CA_L1, CA_L2, CA_L3, CA_L5, CA_L6 > CA_L4

[0171] Condition 5: CA_L1, CA_L2, CA_L3, CA_L6 > CA_L5 > CA_L4

[0172] Condition 6: CA_L1, CA_L2 > CA_L6 > CA_L3, CA_L4, CA_L5

[0173]

[0174] Regarding the refractive index, the refractive index of the third lens (103) and the sixth lens (106) is the maximum among the lenses and may be greater than 1.6, for example, greater than 1.65. Either of the second lens (102) and the fifth lens (105) may have the minimum refractive index among the lenses. For example, the refractive index of either the second lens (102) or the fifth lens (105) may be the minimum among the lenses and may be less than 1.6, for example, less than 1.55. The difference between the maximum refractive index and the minimum refractive index may be 0.1 or greater.

[0175] The refractive index of each lens can satisfy any one of the following conditions.

[0176] Condition 1: n3, n4, n6 > n1 > n2, n5

[0177] Condition 2: n1, n3, n4, n6 > n2 = n5

[0178] Condition 3: n3 = n6 > n1, n2, n4, n5

[0179] Condition 4: n3, n6 > n4 > n1, n2, n5

[0180]

[0181] When comparing the Abbe numbers, the Abbe numbers of the second lens (102) and the fifth lens (105) are the maximum among the lenses and may be 50 or more. The Abbe numbers of the third lens (103) and the sixth lens (106) are the minimum among the lenses and may be 30 or less. The difference between the maximum refractive index and the minimum Abbe number may be 30 or more.

[0182] The Abbe number of each lens can satisfy any one of the following conditions.

[0183] Condition 1: v2, v5 > v1 > v3, v4, v6

[0184] Condition 2: v2 = v5 > v1, v3, v4, v6

[0185] Condition 3: v1, v2, v4, v5 > v6 = v3

[0186] Condition 4: v1, v2, v5 > v4 > v3, v6

[0187]

[0188] The focal lengths (F1, F2, F4) of the first, second, and fourth lenses (101, 102, 104) may have a positive (+) sign. The first, second, and fourth lenses (101, 102, 104) may have a positive (+) refractive power. The focal lengths (F3, F5, F6) of the third, fifth, and sixth lenses (103, 105, 106) may have a negative (-) sign. The third, fifth, and sixth lenses (103, 105, 106) may have a negative (-) refractive power.

[0189] When comparing the absolute values ​​of the focal lengths, the focal length of the fifth lens (105) is the maximum among the lenses and may be 20 or more and 30 or less. The focal length of the sixth lens (106) is the minimum among the lenses, and the absolute value of the focal length of the sixth lens (106) may be 5 or more and 10 or less.

[0190] The absolute value of the focal length of each lens can satisfy any one of the following conditions.

[0191] Condition 1: |f3|, |f4|, |f5| > |f1| > |f2|, |f6|

[0192] Condition 2: |f1|, |f3|, |f4|, |f5| > |f2| > |f6|

[0193] Condition 3: |f4|, |f5| > |f3| > |f1|, |f2|, |f6|

[0194] Condition 4: |f5| > |f4| > |f1|, |f2|, |f3|, |f6|

[0195] Condition 5: |f5| > |f1|, |f2|, |f3|, |f4|, |f6|

[0196] Condition 6: |f1|, |f2|, |f3|, |f4|, |f5| > |f6|

[0197]

[0198] The combined focal length (f_LG1) of the first lens group (LG1) can have a positive (+) sign. The first lens group (LG1) can have a positive (+) combined refractive power. The combined focal length (f_LG2) of the second lens group (LG2) can have a negative (-) sign. The second lens group (LG2) can have a negative (-) combined refractive power. Through this, light incident from the object side can move away from the optical axis direction and then converge back towards the optical axis direction, thereby forming a stable optical path.

[0199] When comparing the combined focal lengths of the first and second lens groups (LG1, LG2) in absolute terms, the combined focal length of the second lens group (LG2) may be the largest, and the combined focal length of the first lens group (LG1) may be the smallest. The relationship between the combined focal lengths of the first and second lens groups (LG1, LG2) may satisfy |f_LG2| > |f_LG1|.

[0200]

[0201] The thickness (CT1) of the first lens (101) may have a difference between the maximum and minimum thickness of at least 1.5 times, for example, in the range of 1.5 to 2 times, with the center thickness (CT1) being maximum and the edge thickness (ET1) being minimum. The thickness (T2) of the second lens (102) may be minimum at the center and maximum at the edge, with the maximum thickness being in the range of 1 to 1.5 times the minimum thickness. The thickness (T3) of the third lens (103) may be minimum at the center and maximum at the edge, with the maximum thickness being in the range of 1 to 1.5 times the minimum thickness. The thickness (T4) of the fourth lens (104) may be maximum at the center and minimum at the edge, with the maximum thickness being in the range of 1 to 1.5 times the minimum thickness. The thickness (T5) of the fifth lens (105) may be minimum at the center and maximum at the edge, and the maximum thickness is in the range of 1 to 1.5 times the minimum thickness. The thickness (T6) of the sixth lens (106) may be minimum at the center and maximum at the edge, and the maximum thickness is in the range of 1 to 1.5 times the minimum thickness.

[0202]

[0203] The thickness of each lens can satisfy any one of the following conditions.

[0204] Condition 1: 1.5 < CT1 / ET1 < 2, 0.5 < ET1 / CT1 < 1

[0205] Condition 2: 1 < CT2 / ET2 < 1.5, 0.5 < ET2 / CT2 < 1

[0206] Condition 3: 0.5 < CT3 / ET3 < 1, 1 < ET3 / CT3 < 1.5

[0207] Condition 4: 1 < CT4 / ET4 < 1.5, 0.5 < ET4 / CT4 < 1

[0208] Condition 5: 0.5 < CT5 / ET5 < 1, 1 < ET5 / CT5 < 1.5

[0209] Condition 6: 0.5 < CT6 / ET6 < 1, 1 < ET6 / CT6 < 1.5

[0210] Condition 7: 1 < ΣCT / ΣET < 1.5, 0.5 < ΣET / ΣCT < 1

[0211]

[0212] Among the gaps between lenses (G1, G2, G3, G4, G5) having gaps between adjacent lenses, the gap (LG1) between the first and second lenses (101, 102) may have a maximum center and a minimum edge. The gap (LG2) between the second and third lenses (102, 103) may have a minimum center and a maximum edge. The gap (LG3) between the third and fourth lenses (103, 104) may have a minimum center and a maximum edge. The gap (G4) between the fourth and fifth lenses (104, 105) may have a maximum edge and a minimum center. The fifth gap (G5) between the fifth and sixth lenses (105, 106) may have a maximum center and a minimum edge.

[0213]

[0214] FIG. 6 is a graph showing the aberration characteristics in the first mode of the optical system according to the first embodiment of the present invention, and FIG. 7 is a graph showing the aberration characteristics in the second mode of the optical system according to the first embodiment of the present invention. The aberration graphs in FIG. 6 and FIG. 7 show the measurement of longitudinal spherical aberration, astigmatic field curves, and distortion from left to right. In FIG. 6 and FIG. 7, the X-axis may represent focal length (mm) and distortion (%), and the Y-axis may represent the height of the image. Additionally, the graph for longitudinal spherical aberration is for light in the wavelength bands of approximately 435 nm, approximately 486 nm, approximately 546 nm, approximately 587 nm, and approximately 656.3 nm, and the graphs for astigmatic field curves and distortion are for light in the wavelength band of approximately 546 nm. In the aberration diagrams of FIGS. 6 and 7, it can be interpreted that the closer each curve is to the Y-axis, the better the aberration correction function is. In the optical system (1000) according to the first embodiment, it can be seen that the measured values ​​are adjacent to the Y-axis in almost all areas. That is, the optical system (1000) according to the first embodiment has improved resolution and can have good optical performance not only in the center of the field of view (FOV) but also in the periphery.

[0215]

[0216] FIG. 8 is a graph showing the relative illumination ratio (Relative Illumination Versus Relative Field) of an optical system according to the first embodiment of the present invention operating in a first mode, and FIG. 9 is a graph showing the relative illumination ratio of an optical system according to the first embodiment of the present invention operating in a second mode. FIG. 8 and FIG. 9 are graphs showing the relative illumination ratio or relative illumination (RI) from the center of the image sensor in the optical system to the image height, i.e., from 0 to the maximum height (MaxF = 1F). It can be seen that a relative illumination ratio of 30% or more, for example, exceeding 40%, appears from the center of the image sensor to the diagonal end (1.0F). That is, it can be seen that there is almost no difference in the relative illumination between the first mode and the second mode of the first embodiment of the present invention from the optical axis to the end of the effective area. Accordingly, since the minimum illumination exceeds 40% from the center of the image sensor to the end, more accurate sensing values ​​can be obtained across the entire area of ​​the image sensor.

[0217]

[0218] The optical system according to the second embodiment of the invention will be described.

[0219] FIG. 10 is a configuration diagram of an optical system according to the second embodiment of the present invention operating in a first mode, FIG. 11 is a configuration diagram of an optical system according to the second embodiment of the present invention operating in a second mode, FIG. 12 is a table showing the aspherical coefficients of lenses in the optical system according to the second embodiment of the present invention, FIG. 13 is a graph showing data on the diffraction MTF of the optical system according to the second embodiment of the present invention operating in a first mode, FIG. 14 is a graph showing data on the diffraction MTF of the optical system according to the second embodiment of the present invention operating in a first mode, FIG. 15 is a graph showing data on the aberration characteristics of the optical system according to the second embodiment of the present invention operating in a first mode, FIG. 16 is a graph showing data on the aberration characteristics of the optical system according to the second embodiment of the present invention operating in a second mode, FIG. 17 is a graph showing the peripheral light intensity ratio of the optical system according to the second embodiment of the present invention operating in a first mode, and FIG. 18 is the second embodiment of the This is a graph showing the ambient light ratio of an optical system according to the second embodiment.

[0220] Referring to FIG. 10, the optical system (1100) includes a lens portion, and the lens portion may include first to sixth lenses (201 to 206). The first to sixth lenses (201 to 206) may be arranged sequentially along the optical axis (OA) of the optical system (1100). Light corresponding to information about an object may pass through the first to sixth lenses (201 to 206) and a filter (400) and be incident on an image sensor (300). The optical axis (OA) may refer to the central axis of light incident from the first lens (201) to the image sensor (300).

[0221]

[0222] The first light path control member (211) may be positioned on the object side of the first lens (201). The first light path control member (211) may include a plastic or glass material. The first light path control member (211) can change the path of light incident from the outside. The first light path control member (211) may include a mirror and a prism.

[0223] The first light path control member (211) can rotate the light path by 90°. The first light path control member (211) includes an incident surface (P1) into which light is incident, a reflective surface (RS1) that reflects the incident light, and an exit surface (P2) that emits the reflected light. The reflective surface (RS1) has an inclination angle of 45° and reflects the main beam of the incident light by 90°, thereby serving to reflect the incident light to the first lens (201). The first light path control member (211) can change the light path to the first direction (X-axis direction) by reflecting the light incident in the second direction (Y-axis direction).

[0224] In addition, to reduce the length in the direction of the first axis (Y-axis) of the optical system, the angle formed by the reflective surface (RS1) and the outgoing surface (P2) in the first optical path control member (211) can be changed from about 45 degrees to about 43 degrees or about 47 degrees. The angle formed by the reflective surface (RS1) and the outgoing surface (P2) in the first optical path control member (211) can be changed to be greater or smaller than about 45 degrees depending on the position where the image sensor is placed.

[0225] For example, if the direction of light incident from the object side of the first light path control member (211) and the direction of light incident on the image sensor are the same direction, the angle formed by the reflective surface (RS1) and the exit surface (P2) in the first light path control member (211) can be changed to approximately 43 degrees. If the direction of light incident on the lens placed on the object side of the first light path control member (211) and the direction of light incident on the image sensor are opposite directions, the angle formed by the reflective surface (RS1) and the exit surface (P2) in the first light path control member (211) can be changed to approximately 47 degrees. Through this, the size of the optical system can be reduced within a range where the change in optical system performance is minimal.

[0226]

[0227] The first lens (201) may be positioned closest to the object side. The first lens (201) may be positioned furthest from the sensor side. The first lens (201) may have a positive (+) refractive power at the optical axis (OA). The first lens (201) may include plastic or glass material. For example, the first lens (201) may be provided with plastic material.

[0228] With respect to the optical axis (OA), the first surface (S1) on the object side of the first lens (201) may be convex, and the second surface (S2) on the sensor side may be concave. The first lens (201) may have a meniscus shape that is convex toward the object side. The first lens (201) may have a meniscus shape that is concave toward the sensor side. The first lens (201) may have an aspherical surface. The aspherical coefficients of the first surface (S1) and the second surface (S2) of the first lens (101) may be provided as L1S1 and L1S2 of FIG. 12. At least one or both of the first surface (S1) and the second surface (S2) of the first lens (201) may be provided without a critical point from the optical axis to the end of the effective area.

[0229]

[0230] The second lens (202) may be positioned second from the object side. The second lens (202) may be positioned fifth from the sensor side. The second lens (202) may be positioned between the first lens (201) and the third lens (203). The second lens (202) may have a positive (+) refractive power. The second lens (202) may include plastic or glass material. For example, the second lens (202) may be provided with plastic material.

[0231] With respect to the optical axis, the object-side third surface (S3) of the second lens (202) may be convex, and the sensor-side fourth surface (S4) may be convex. The second lens (202) may have a shape with both sides convex. The second lens (202) may be made of plastic material and may have an aspherical surface. The aspherical coefficients of the third surface (S3) and the fourth surface (S4) may be provided as L2S1 and L2S2 of FIG. 12. At least one or both of the third surface (S3) and the fourth surface (S4) of the second lens (202) may be provided without a threshold point from the optical axis to the end of the effective area.

[0232]

[0233] The third lens (203) may be positioned as the third lens from the object side. The third lens (203) may be positioned as the fourth lens from the sensor side. The third lens (203) may be positioned between the second lens (202) and the fourth lens (204). The third lens (203) may have a negative (-) refractive power at the optical axis (OA). The third lens (203) may include plastic or glass material. For example, the third lens (203) may be provided with plastic material.

[0234] With respect to the optical axis, the object-side fifth surface (S5) of the third lens (203) may be concave, and the sensor-side sixth surface (S6) may be convex. The third lens (203) may have a meniscus shape with the object side being concave. The third lens (203) may have a meniscus shape with the sensor side being convex. The third lens (203) may be made of plastic material and may have an aspherical surface. The aspherical coefficients of the fifth surface (S5) and the sixth surface (S6) may be provided as L3S1 and L3S2 of FIG. 12. At least one or both of the fifth surface (S5) and the sixth surface (S6) of the third lens (203) may be provided without a critical point from the optical axis to the end of the effective area.

[0235]

[0236] The fourth lens (204) may be positioned as the fourth lens from the object side. The fourth lens (204) may be positioned as the third lens from the sensor side. The fourth lens (204) may be positioned between the third lens (203) and the fifth lens (205). The fourth lens (204) may have a negative (-) refractive power. The fourth lens (204) may include plastic or glass materials. For example, the fourth lens (204) may be provided with a plastic material.

[0237] With respect to the optical axis, the object-side 7th surface (S7) of the 4th lens (204) may be convex, and the sensor-side 8th surface (S8) may be concave. The 4th lens (204) may have a meniscus shape with the object side being convex. The 4th lens (204) may have a meniscus shape with the sensor side being concave. The 4th lens (204) may be made of plastic material and may have an aspherical surface. The aspherical coefficients of the 7th surface (S7) and the 8th surface (S8) may be provided as L4S1 and L4S2 of FIG. 12. At least one or both of the 7th surface (S7) and the 8th surface (S8) of the 4th lens (204) may be provided without a critical point from the optical axis to the end of the effective area.

[0238]

[0239] The fifth lens (205) may be positioned as the fifth lens from the object side. The fifth lens (205) may be positioned as the second lens from the sensor side. The fifth lens (205) may be positioned between the fourth lens (204) and the sixth lens (206). The fifth lens (205) may have a positive (+) refractive power. The fifth lens (205) may include plastic or glass materials. For example, the fifth lens (205) may be provided with a plastic material.

[0240] With respect to the optical axis (OA), the fifth lens (205) may have a convex ninth surface (S9) on the object side and a concave tenth surface (S10) on the sensor side. The fifth lens (205) may have a meniscus shape that is convex on the object side at the optical axis (OA). The fifth lens (205) may have a meniscus shape that is concave on the sensor side at the optical axis (OA). The fifth lens (205) is made of plastic material and may have an aspherical surface. The aspherical coefficients of the ninth surface (S9) and the tenth surface (S10) may be provided as L5S1 and L5S2 of FIG. 12. At least one or both of the ninth surface (S9) and the tenth surface (S10) of the fifth lens (205) may be provided without a threshold point from the optical axis to the end of the effective area.

[0241]

[0242] The sixth lens (206) may be positioned furthest from the object side. The sixth lens (206) may be positioned closest to the sensor side. The sixth lens (206) may have negative (-) refractive power. The sixth lens (206) may include plastic or glass material. For example, the sixth lens (206) may be provided with plastic material.

[0243] With respect to the optical axis (OA), the 6th lens (206) may have an object-side 11th surface (S11) that is convex and a sensor-side 12th surface (S12) that is concave. The 6th lens (206) may have a meniscus shape with the object side being convex. The 6th lens (206) may have a meniscus shape with the sensor side being concave. The 6th lens (206) is made of plastic material and may have an aspherical surface. The aspherical coefficients of the 11th surface (S11) and the 12th surface (S12) may be provided as L6S1 and L6S2 of FIG. 12. At least one or both of the 11th surface (S11) and the 12th surface (S12) of the 6th lens (206) may be provided without a critical point from the optical axis to the end of the effective area.

[0244]

[0245] The second light path control member (212) may be positioned on the sensor side of the sixth lens (206). The second light path control member (212) may be positioned closest to the sensor side. The second light path control member (212) may be positioned furthest from the object side. The second light path control member (212) can change the path of light incident from the outside. The second light path control member (212) may include a reflector and a prism.

[0246] The second light path control member (212) can rotate the light path by 90°. The second light path control member (212) includes an incident surface (P3) where light is incident, a reflective surface (RS2) that reflects the incident light, and an output surface (P4) that emits the reflected light. The reflective surface (RS2) has an inclination angle of 45° and reflects the main beam of the incident light by 90°, thereby serving to reflect the incident light to the image sensor (300). The second light path control member (212) can change the light path to the second direction (Y-axis direction) by reflecting the light incident in the first direction (X-axis direction).

[0247]

[0248] LensSurfaceRadiusThicknessndvdClearApertureprism1P1infinity8.0001.72329.4994.777 P2infinity0.400 4.0861S15.2001.5001.53755.7303.050 S212.4140.602 2.9982S317.1041.5001.53463.7632.907 S4-6.2990.259 2.7813S5-4.6350.6881.64723.9192.504 S6-9.677Variable (D1) 2.2754S712.7030.6431.53463.7632.020 S83.3290.262 2.1085S96.0451.5001.55349.7562.121 S1017.6801.229 2.2576S1110.3970.5001.54750.9562.467 S126.011 Variable (D2) 2.807prism2P3infinity6.4001.65233.8423.632 P4infinity0.300 4.329filter 0.210 5.138air 0.300 5.187image 0.000 5.318

[0249] Table 4 shows the surface number, radius of curvature, thickness of the center of each lens or distance between lens surfaces, index, nd, Abbe number (Abbe,vd), clear aperture, and focal length of the lens according to the second embodiment of the present invention. At this time, the units of the radius of curvature and the thickness or distance may be mm.

[0250] In Table 4, the thickness of the first optical path control member (211) and the second optical path control member (212) may refer to the thickness along the optical axis (OA). For example, the thickness of the first optical path control member (211) may refer to the sum of the thickness from the incident surface (P1) to the reflection surface (RS1) along the y-axis and the thickness from the reflection surface (RS1) to the exit surface (P2) along the x-axis. The thickness of the first optical path control member (212) may refer to the sum of the thickness from the incident surface (P1) to the reflection surface (RS1) along the y-axis and the thickness from the reflection surface (RS2) to the exit surface (P4) along the x-axis.

[0251] Additionally, the thickness from the incident surface (P1) to the reflection surface (RS1) along the y-axis of the first light path control member (211) and the thickness from the reflection surface (RS1) to the exit surface (P2) along the x-axis of the first light path control member (211) may be the same. The thickness from the incident surface (P3) to the reflection surface (RS2) along the y-axis of the second light path control member (212) and the thickness from the reflection surface (RS2) to the exit surface (P4) along the x-axis of the second light path control member (212) may be the same.

[0252] According to a modified example, the thickness from the incident surface (P1) to the reflection surface (RS1) along the y-axis of the first light path control member (211) and the thickness from the reflection surface (RS1) to the exit surface (P2) along the x-axis of the first light path control member (211) may be different. The thickness from the incident surface (P3) to the reflection surface (RS2) along the y-axis of the second light path control member (212) and the thickness from the reflection surface (RS2) to the exit surface (P4) along the x-axis of the second light path control member (212) may be different.

[0253]

[0254] 1st mode 2nd mode D10.5772.237D21.9270.266

[0255] Table 5 shows the distance between lenses (D1, D2) that varies when operating in either the first mode or the second mode in the optical system according to the second embodiment of the present invention. Here, the first mode refers to the case of photographing an object located at infinity, and the second mode may refer to the case of photographing an object located at a macroscopic distance (e.g., within 100 mm).

[0256] In the optical system according to the second embodiment, the distance between adjacent lens groups may change during the process of changing from the first mode to the second mode. The first lens group (LG1) may be fixed, and the second lens group (LG2) may be movable. The first lens group (LG1) may be a fixed group, and the second lens group (LG2) may be a movable group.

[0257] When operating from the first mode to the second mode, the distance (D1) between the first lens group (LG1) and the second lens group (LG2) may increase, and the distance (D2) between the second lens group (LG2) and the second light path control member (212) may decrease. When operating from the second mode to the first mode, the distance (D1) between the first lens group (LG1) and the second lens group (LG2) may decrease, and the distance (D2) between the second lens group (LG2) and the second light path control member (212) may increase. The stroke length of the second lens group (LG2) may satisfy 1.5 mm to 2.0 mm, and preferably, about 1.660 mm. As the second lens group (LG2) moves, the optical performance of the optical system (1100) may change.

[0258]

[0259] EFL(F)17.060Fno2.797BFL_19.137HFOV16.522BFL_27.476EPD6.100f115.532ET10.825f28.81 0ET20.855f3-14.523ET31.006f4-8.646ET40.978f515.882ET51.389f6-27.122ET60.669CA_Max 6.048L_CT_max1.500CA_Min4.128L_CT_min0.500CA_Aver5.049L_CT_aver1.055ΣCG2.352ΣCT6. 331TTL18.396LG2_stroke1.660f_LG19.801TD_LG14.549f_LG2-10.236TD_LG24.134ImgH10.636

[0260] Table 6 relates to the items of the mathematical formulas described above in the optical system (1100) of the second embodiment, including the effective focal length (EFL(F)(mm)) in the first mode of the optical system (1100), the distance from the sensor side of the last lens to the image sensor (BFL(mm)), the horizontal field of view (HFOV(degree)), the focal lengths (f1~f6)(mm) of the first to sixth lenses (201~206), the edge thickness (ET1~ET6), the length of each lens group in the optical axis direction (TD_LG1, TD_LG2), the focal lengths (f_LG1, f_LG2)(mm) of the first to second lens groups (LG1, LG2), the size of the entrance pupil (EPD(mm)), the optical axis distance (TD(mm)) from the first lens (201) to the sixth lens (206), the brightness (Fno) of the optical system (1100), and the stroke of the second lens group (LG2). This relates to the length (LG2_stroke), the total optical axis distance of the optical system (1100) TTL (mm), ImgH (mm), the maximum effective diameter (CA_Max), the minimum effective diameter (CA_Min), the average effective diameter (CA_Aver), the maximum center thickness (L_CT_max), the minimum center thickness (L_CT_min), the average center thickness (L_CT_aver), etc., among the first to sixth lenses (201~206).

[0261]

[0262] In the following, the center thickness of the first to sixth lenses (201 to 206) is denoted as CT1 to CT6, the edge thickness of the end of the effective area of ​​each lens is denoted as ET1 to ET6, and the center gap between two adjacent lenses is denoted as CG1 to CG5. BFL (Back focal length) is the optical axis distance from the image sensor (300) to the center of the last lens. TTL is the optical axis distance from the center of the first surface (S1) of the first lens (201) to the top surface of the image sensor (300). In the following, the description of the relationship between the first optical path control member (211) and the second optical path control member (212) is partially omitted.

[0263]

[0264] When comparing the absolute values ​​of the radius of curvature of each lens, the radius of curvature of the 10th surface (S10) of the 5th lens (205) at the optical axis (OA) may be the maximum among the lenses, and the radius of curvature of the 8th surface (S8) of the 4th lens (204) may be the minimum among the lenses. The absolute value of the radius of curvature of the 1st surface (S1) of the 1st lens (201) may be smaller than the absolute value of the radius of curvature of the 2nd surface (S2). The absolute value of the radius of curvature of the 3rd surface (S3) of the 2nd lens (202) may be larger than the absolute value of the radius of curvature of the 4th surface (S4). The absolute value of the radius of curvature of the 5th surface (S5) of the 3rd lens (203) may be smaller than the absolute value of the radius of curvature of the 6th surface (S6). The absolute value of the radius of curvature of the 7th surface (S7) of the 4th lens (204) may be greater than the absolute value of the radius of curvature of the 8th surface (S8). The absolute value of the radius of curvature of the 9th surface (S9) of the 5th lens (205) may be smaller than the absolute value of the radius of curvature of the 10th surface (S10). The absolute value of the radius of curvature of the 11th surface (S11) of the 6th lens (206) may be greater than the absolute value of the radius of curvature of the 12th surface (S12).

[0265] The ratio of the radius of curvature of each lens can satisfy the following conditions.

[0266] Condition 1: 0.1 < |L1R1 / L1R2| < 0.5

[0267] Condition 2: 2.5 < |L2R1 / L2R2| < 3

[0268] Condition 3: 0.1 < |L3R1 / L3R2| < 0.5

[0269] Condition 4: 3.5 < |L4R1 / L4R2| < 4

[0270] Condition 5: 0.1 < |L5R1 / L5R2| < 0.5

[0271] Condition 6: 1.5 < |L6R1 / L6R2| < 2

[0272]

[0273] When describing the center thickness of the lenses based on the optical axis, the center thickness (CT1, CT2, CT5) of the first lens (201), the second lens (202), and the fifth lens (205) is the maximum among the lenses, and the center thickness (CT6) of the sixth lens (206) is the minimum among the lenses. The difference between the maximum center thickness and the minimum center thickness among the lenses may be in the range of 0.8 mm or more and 1.3 mm or less.

[0274] The center thickness of each lens can satisfy any one of the following conditions.

[0275] Condition 1: CT1 = CT2 = CT5 > CT3, CT4, CT6

[0276] Condition 2: CT1, CT2, CT5 > CT3 > CT4, CT6

[0277] Condition 3: CT1, CT2, CT3, CT5 > CT4 > CT6

[0278] Condition 4: CT1, CT2, CT3, CT4, CT5 > CT6

[0279]

[0280] When zooming, the gap (CG1) between the first lens (201) and the second lens (202), the gap (CG2) between the second lens (202) and the third lens (203), the gap (CG4) between the fourth lens (204) and the fifth lens (205), and the gap (CG5) between the fifth lens (205) and the sixth lens (206) do not change, while the gap (CG3) between the third lens (203) and the fourth lens (204) may change. Among the center gaps between the lenses that do not change, the gap (CG5) between the fifth lens (205) and the sixth lens (206) may be maximum, and the gap (CG2) between the second lens (202) and the third lens (203) may be minimum. Among the gaps between the lenses, the difference between the maximum center gap and the minimum center gap may be 0.5 mm or more, for example, in the range of 0.5 mm to 1.0 mm.

[0281] The center spacing between each lens can satisfy the following conditions.

[0282] Condition 1: CG5 > CG1 > CG2, CG4

[0283] Condition 2: CG1, CG4, CG5 > CG2

[0284] Condition 3: CG1, CG5 > CG4 > CG2

[0285] Condition 4: CG5 > CG1, CG2, CG4

[0286]

[0287] Regarding the effective aperture, the lens having the maximum effective aperture may be the first lens (201). Here, the effective aperture is the average of the effective aperture on the object side and the effective aperture on the sensor side of each lens. The lens surface having the maximum effective aperture may be the first surface (S1) of the first lens (201). The lens having the minimum effective aperture may be the fourth lens (204). The lens surface having the minimum effective aperture may be the seventh surface (S7) of the fourth lens (204). The effective apertures of the first to sixth lenses (201-206) may be larger than the diagonal length of the image sensor (300).

[0288] The effective diameter of each lens can satisfy any one of the following conditions.

[0289] Condition 1: CA_L1 > CA_L2, CA_L3, CA_L4, CA_L5, CA_L6

[0290] Condition 2: CA_L1 > CA_L2 > CA_L3, CA_L4, CA_L5, CA_L6

[0291] Condition 3: CA_L1, CA_L2, CA_L6 > CA_L3 > CA_L4, CA_L5

[0292] Condition 4: CA_L1, CA_L2, CA_L3, CA_L5, CA_L6 > CA_L4

[0293] Condition 5: CA_L1, CA_L2, CA_L3, CA_L6 > CA_L5 > CA_L4

[0294] Condition 6: CA_L1, CA_L2 > CA_L6 > CA_L3, CA_L4, CA_L5

[0295]

[0296] Regarding the refractive index, the refractive index of the third lens (203) is the maximum among the lenses and may be greater than 1.6, for example, greater than 1.63. Either the second lens (202) or the fourth lens (204) may have the minimum refractive index among the lenses. For example, the refractive index of either the second lens (202) or the fourth lens (204) may be the minimum among the lenses and may be less than 1.6, for example, less than 1.55. The difference between the maximum refractive index and the minimum refractive index may be 0.1 or greater.

[0297] The refractive index of each lens can satisfy any one of the following conditions.

[0298] Condition 1: n3, n5, n6 > n1 > n2, n4

[0299] Condition 2: n1, n3, n5, n6 > n2 = n4

[0300] Condition 3: n3 > n1, n2, n4, n5, n6

[0301] Condition 4: n3 > n5 > n1, n2, n4, n6

[0302] Condition 5: n3, n5 > n6 > n1, n2, n4

[0303]

[0304] When comparing the Abbe numbers, the Abbe numbers of the second lens (202) and the fourth lens (204) are the maximum among the lenses and may be 50 or more. The Abbe number of the third lens (203) is the minimum among the lenses and may be 30 or less. The difference between the maximum refractive index and the minimum Abbe number may be 30 or more.

[0305] The Abbe number of each lens can satisfy any one of the following conditions.

[0306] Condition 1: v2, v4 > v1 > v3, v5, v6

[0307] Condition 2: v2 = v4 > v1, v3, v5, v6

[0308] Condition 3: v1, v2, v4, v5, v6 > v3

[0309] Condition 4: v1, v2, v4, v6 > v5 > v3

[0310] Condition 5: v1, v2, v4 > v6 > v3, v5

[0311]

[0312] The focal lengths (F1, F2, F5) of the first, second, and fifth lenses (201, 202, 205) may have a positive (+) sign. The first, second, and fifth lenses (201, 202, 205) may have a positive (+) refractive power. The focal lengths (F3, F4, F6) of the third, fourth, and sixth lenses (203, 204, 206) may have a negative (-) sign. The third, fourth, and sixth lenses (203, 204, 206) may have a negative (-) refractive power.

[0313] When comparing the focal lengths in absolute values, the focal length of the sixth lens (206) is the maximum among the lenses and may be 20 or more and 30 or less. The focal length of the fourth lens (204) is the minimum among the lenses, and the absolute value of the focal length of the fourth lens (204) may be 5 or more and 10 or less.

[0314] The absolute value of the focal length of each lens can satisfy any one of the following conditions.

[0315] Condition 1: |f5|, |f6| > |f1| > |f2|, |f3|, |f4|

[0316] Condition 2: |f1|, |f3|, |f5|, |f6| > |f2| > |f4|

[0317] Condition 3: |f1|, |f5|, |f6| > |f3| > |f2|, |f4|

[0318] Condition 4: |f1|, |f3|, |f5|, |f6|, |f2| > |f4|

[0319] Condition 5: |f6| > |f5| > |f1|, |f2|, |f3|, |f4|

[0320] Condition 6: |f6| > |f1|, |f2|, |f3|, |f4|, |f5|

[0321]

[0322] The combined focal length (f_LG1) of the first lens group (LG1) can have a positive (+) sign. The first lens group (LG1) can have a positive (+) combined refractive power. The combined focal length (f_LG2) of the second lens group (LG2) can have a negative (-) sign. The second lens group (LG2) can have a negative (-) combined refractive power. Through this, light incident from the object side can move away from the optical axis direction and then converge back towards the optical axis direction, thereby forming a stable optical path.

[0323] When comparing the combined focal lengths of the first and second lens groups (LG1, LG2) in absolute terms, the combined focal length of the second lens group (LG2) may be the largest, and the combined focal length of the first lens group (LG1) may be the smallest. The relationship between the combined focal lengths of the first and second lens groups (LG1, LG2) may satisfy |f_LG2| > |f_LG1|.

[0324]

[0325] The thickness (CT1) of the first lens (201) may have a difference between the maximum and minimum thickness of at least 1.5 times, for example, in the range of 1.5 to 2 times, with the center thickness (CT1) being maximum and the edge thickness (ET1) being minimum. The thickness (T2) of the second lens (202) may be maximum at the center and minimum at the edge, with the maximum thickness being in the range of 1.5 to 2 times the minimum thickness. The thickness (T3) of the third lens (203) may be minimum at the center and maximum at the edge, with the maximum thickness being in the range of 1 to 1.5 times the minimum thickness. The thickness (T4) of the fourth lens (204) may be minimum at the center and maximum at the edge, with the maximum thickness being in the range of 1.5 to 2 times the minimum thickness. The thickness (T5) of the fifth lens (205) may be maximum at the center and minimum at the edge, and the maximum thickness is in the range of 1 to 1.5 times the minimum thickness. The thickness (T6) of the sixth lens (206) may be minimum at the center and maximum at the edge, and the maximum thickness is in the range of 1 to 1.5 times the minimum thickness.

[0326]

[0327] The thickness of each lens can satisfy any one of the following conditions.

[0328] Condition 1: 1.5 < CT1 / ET1 < 2, 0.5 < ET1 / CT1 < 1

[0329] Condition 2: 1.5 < CT2 / ET2 < 2, 0.5 < ET2 / CT2 < 1

[0330] Condition 3: 0.5 < CT3 / ET3 < 1, 1 < ET3 / CT3 < 1.5

[0331] Condition 4: 0.5 < CT4 / ET4 < 1, 1.5 < ET4 / CT4 < 2

[0332] Condition 5: 1 < CT5 / ET5 < 1.5, 0.5 < ET5 / CT5 < 1

[0333] Condition 6: 0.5 < CT6 / ET6 < 1, 1 < ET6 / CT6 < 1.5

[0334] Condition 7: 1 < ΣCT / ΣET < 1.5, 0.5 < ΣET / ΣCT < 1

[0335]

[0336] Among the gaps between lenses (G1, G2, G3, G4, G5) having gaps between adjacent lenses, the gap (LG1) between the first and second lenses (201, 202) may have a maximum center and a minimum edge. The gap (LG2) between the second and third lenses (202, 203) may have a minimum center and a maximum edge. The gap (LG3) between the third and fourth lenses (203, 204) may have a minimum center and a maximum edge. The gap (G4) between the fourth and fifth lenses (204, 205) may have a minimum edge and a maximum center. The fifth gap (G5) between the fifth and sixth lenses (205, 206) may have a maximum center and a minimum edge.

[0337]

[0338] FIG. 15 is a graph showing the aberration characteristics in the first mode of the optical system according to the second embodiment of the present invention, and FIG. 16 is a graph showing the aberration characteristics in the second mode of the optical system according to the second embodiment of the present invention. The aberration graphs in FIG. 15 and FIG. 16 show the longitudinal spherical aberration, astigmatic field curves, and distortion measured from left to right. In FIG. 15 and FIG. 16, the X-axis may represent the focal length (mm) and distortion (%), and the Y-axis may represent the height of the image. Additionally, the graph for longitudinal spherical aberration is for light in the wavelength bands of approximately 435 nm, approximately 486 nm, approximately 546 nm, approximately 587 nm, and approximately 656.3 nm, and the graphs for astigmatic field curves and distortion are for light in the wavelength band of approximately 546 nm. In the aberration diagrams of FIGS. 15 and 16, it can be interpreted that the closer each curve is to the Y-axis, the better the aberration correction function is. In the optical system (1100) according to the second embodiment, it can be seen that the measured values ​​are adjacent to the Y-axis in almost all areas. That is, the optical system (1100) according to the second embodiment has improved resolution and can have good optical performance not only in the center of the field of view (FOV) but also in the periphery.

[0339]

[0340] FIG. 17 is a graph showing the relative illumination ratio (Relative Illumination Versus Relative Field) of an optical system according to the second embodiment of the present invention operating in a first mode, and FIG. 18 is a graph showing the relative illumination ratio of an optical system according to the second embodiment of the present invention operating in a second mode. FIG. 17 and FIG. 18 are graphs showing the relative illumination ratio or relative illumination (RI) from the center of the image sensor in the optical system to the image height, i.e., from 0 to the maximum height (MaxF = 1F). It can be seen that a relative illumination ratio of 20% or more, for example, exceeding 30%, appears from the center of the image sensor to the diagonal end (1.0F). That is, it can be seen that there is almost no difference in the relative illumination between the first mode and the second mode of the present embodiment of the present invention from the optical axis to the end of the effective area. Accordingly, since the minimum light intensity from the center to the end of the image sensor exceeds 30%, more accurate sensing values ​​can be obtained across the entire area of ​​the image sensor.

[0341]

[0342] The optical system (1000, 1100) according to the first and second embodiments disclosed above may satisfy at least one or two of the mathematical formulas described below. Accordingly, the optical system (1000, 1100) according to the first and second embodiments may have improved optical characteristics. For example, if the optical system (1000, 1100) satisfies at least one mathematical formula, the optical system (1000, 1100) can effectively control aberration characteristics such as chromatic aberration and distortion aberration, and may have good optical performance not only at the center of the field of view (FOV) but also at the periphery. In addition, the optical system (1000, 1100) may have improved resolution. Furthermore, regarding the meaning of the thickness of the lens at the optical axis (OA) and the spacing of adjacent lenses at the optical axis (OA) described in the mathematical formulas, one may refer to the first and second embodiments disclosed above.

[0343]

[0344] [Mathematical Formula 1]

[0345] 0.5 < TD_LG1 / TD_LG2 < 1.5

[0346] Equation 1 can establish the relationship between the length of the first lens group (LG1) (TD_LG1) and the length of the second lens group (LG2) (TD_LG2) in the direction of the optical axis. Equation 1 is a condition for reducing aberrations and improving optical performance.

[0347] The first lens group (LG1) and the second lens group (LG2) satisfying Equation 1 can appropriately correct astigmatism aberration and coma aberration. In addition, the overall length of the zoom optical system having an appropriate AF correction function can be reduced. In the first and second embodiments of the present invention, Equation 1 can preferably satisfy 0.8 < TD_LG1 / TD_LG2 < 1.2.

[0348]

[0349] [Mathematical Formula 2]

[0350] 15 < EFL(F) < 18

[0351] In Equation 2, EFL(F) is the total focal length of the optical system (1000, 1100). Equation 2 is a condition for limiting zoom optical performance. If the upper limit of Equation 2 is exceeded, it is difficult to secure optical performance due to chromatic aberration, and the amount of movement of each lens group increases significantly during AF correction, making mechanical miniaturization difficult. If it is below the lower limit of Equation 2, there is a problem that the sensitivity of the entire optical system increases. A zoom optical system satisfying Equation 2 can secure substantially useful optical performance. In the first and second embodiments of this invention, Equation 2 can preferably satisfy 16.5 < EFL(F) < 17.5.

[0352]

[0353] [Mathematical Formula 3]

[0354] 5 < BFL_1 < 10

[0355] In Equation 3, BFL is the optical axis distance from the image sensor (300) to the center of the sensor side of the last lens in the first mode. If Equation 3 is satisfied, installation space for the filter (400) and cover glass can be secured, and the assembly of components and coupling reliability can be improved through the gap between the image sensor (300) and the last lens. In the first and second embodiments, Equation 3 can preferably satisfy 7 < BFL_1 < 9.5. If BFL is less than the range of Equation 3, some light proceeding to the image sensor may not be transmitted to the image sensor, which may cause a decrease in resolution. If BFL exceeds the range of Equation 3, stray light may be introduced, and the aberration characteristics of the optical system may be degraded.

[0356]

[0357] [Mathematical Formula 4]

[0358] 40 < Ave_ABV < 60

[0359] In Equation 4, Ave_ABV is the average of the Abbe numbers of the lenses included in the optical system (1000, 1100). When Equation 4 is satisfied, optical performance can be improved by appropriately setting the factors affecting chromatic aberration. In the first and second embodiments, Equation 4 can preferably satisfy 40 < Ave_ABV < 55.

[0360]

[0361] [Mathematical Formula 5]

[0362] 1.5 < Ave_Ind < 1.65

[0363] In Equation 5, Ave_Ind is the average of the refractive indices of the lenses included in the optical system (1000, 1100). If Equation 5 is satisfied, optical performance can be improved by appropriately setting the factors affecting chromatic aberration. In the first and second embodiments, Equation 4 can preferably satisfy 1.54 < Ave_Ind < 1.62.

[0364]

[0365] [Mathematical Formula 6]

[0366] 0.1 < |f_LG1 / f_LG2| < 1

[0367] Equation 6 can establish the relationship between the focal length (f_LG1) of the first lens group (LG1) and the focal length (f_LG2) of the second lens group (LG2). Equation 6 is a condition for reducing aberrations and improving optical performance. The first lens group (LG1) and the second lens group (LG2) satisfying Equation 6 can appropriately correct astigmatism aberration and coma aberration. In the first and second embodiments of the present invention, Equation 6 can preferably satisfy 0.8 < |f_LG1 / f_LG2| < 1.

[0368]

[0369] [Mathematical Formula 7]

[0370] (1st Embodiment) 1 < LG1_stroke < 2

[0371] (Second Embodiment) 1 < LG2_stroke < 2

[0372] Equation 7 can set the range of stroke lengths of the moving lens group. Specifically, in the first embodiment, the range of stroke lengths (LG1_stroke) of the first lens group (LG1) of the moving group can be set, and in the second embodiment, the range of stroke lengths (LG2_stroke) of the second lens group (LG2) can be set. If the upper limit of Equation 7 is exceeded, the stroke length of the moving lens group increases during AF correction, making it difficult to miniaturize the optical system. If the lower limit of Equation 7 is not met, the AF correction performance of the optical system may be degraded. In the first embodiment, Equation 7 can preferably satisfy 1.5 < LG1_stroke < 2, and in the second embodiment, it can preferably satisfy 1.5 < LG2_stroke < 2.

[0373]

[0374] [Mathematical Formula 8]

[0375] 1 < CA_L1 / CA_L4 < 2

[0376] In Equation 8, CA_L1 is the size of the effective aperture of the first lens (101, 201), and CA_L4 is the size of the effective aperture of the fourth lens (104, 204). Here, the size of the effective aperture of the lens is the average of the effective aperture value on the object side of the lens and the effective aperture value on the sensor side of the lens. The first lens (101, 201) is the lens positioned closest to the object side in the first lens group (LG1), and the fourth lens (104, 204) is the lens positioned closest to the object side in the second lens group (LG2). When Equation 8 is satisfied, the light path incident on the first lens group (LG1) and the second lens group (LG2) can be appropriately set to improve aberrations and improve optical performance. In the first and second embodiments, Equation 8 can preferably satisfy 1 < CA_L1 / CA_L4 < 1.5.

[0377]

[0378] [Mathematical Formula 9]

[0379] 1 < EFL(F) / F1 < 1.5

[0380] In Equation 9, EFL(F) is the total effective focal length of the optical system (1000, 1100), and F1 is the focal length of the first lens (101, 201). When Equation 9 is satisfied, the optical system (1000, 1100) can have a set angle of view and an appropriate focal length, and the angle of view can be set large within an appropriate TTL range. If it is below the lower limit of Equation 9, the effective aperture or TTL of the lenses becomes longer, which may cause a problem where the imaging lens system becomes large. If it exceeds the upper limit of Equation 9, the influence of the first lens (101, 201) in the entire optical system decreases, and it is necessary to increase the refractive power of the lenses, which makes it difficult to correct spherical aberration or distortion aberration. In the first and second embodiments, Equation 9 can preferably satisfy 1 < EFL(F) / F1 < 1.2.

[0381]

[0382] [Mathematical Formula 10]

[0383] 1 < TTL / F1 < 1.5

[0384] In Equation 10, F1 is the focal length of the first lens (101, 201), and TTL (Total track length) is the distance (mm) from the center of the first surface (S1) of the first lens (101, 201) to the top surface of the image sensor (300) along the optical axis (OA). When Equation 10 is satisfied, the optical system (1000, 1100) can have a set angle of view and an appropriate focal length. If it is less than the lower limit of Equation 10, the effective aperture or TTL of the lenses becomes longer, which may cause a problem where the imaging lens system becomes larger. If it exceeds the upper limit of Equation 10, the influence of the first lens (101, 201) in the entire optical system decreases, and it is necessary to increase the refractive power of the lenses, which makes it difficult to correct spherical aberration or distortion aberration. In the first to third embodiments, mathematical formula 10 can preferably satisfy 1 < TTL / F1 < 1.3.

[0385]

[0386] [Mathematical Formula 11]

[0387] 10 < TTL < 20

[0388] In Equation 11, TTL (Total track length) refers to the distance (mm) along the optical axis (OA) from the center of the first surface (S1) of the first lens (101) to the top surface of the image sensor (300). In the first and second embodiments, Equation 11 can preferably satisfy 15 < TTL < 20.

[0389]

[0390] [Mathematical Formula 12]

[0391] 8 < ImgH < 12

[0392] In Equation 12, ImgH represents the maximum diagonal length of the image sensor (300). Equation 12 can set the diagonal size (ImgH) of the image sensor (300) and can provide an optical system having a large mobile image sensor size. In the first and second embodiments, Equation 12 can preferably satisfy 9 < ImgH < 11.

[0393]

[0394] [Mathematical Formula 13]

[0395] 2 < Fno < 3

[0396] Equation 13 can set the range of Fno of the optical system (1000, 1100). When Equation 13 is satisfied, an image of appropriate brightness can be provided, and a large amount of light can be received by the image sensor. In the first and second embodiments, Equation 13 can preferably satisfy 2.5 < Fno < 3.

[0397]

[0398] [Mathematical Formula 14]

[0399] 2 < f1 / |L1R1| < 4

[0400] In Equation 24, f1 is the focal length of the first lens (101, 201), and L1R1 is the radius of curvature of the object side of the first lens (101, 201). Equation 24 is a condition for OIS correction by tilting the prism lens; if it is below the lower limit, there is a problem of significant reduction in resolution when correcting OIS through prism lens tilting, and if it exceeds the upper limit, there is a problem of Fno becoming larger. In the first and second embodiments, Equation 24 can preferably satisfy 2.5 < f1 / |L1R1| < 3.5.

[0401]

[0402] [Mathematical Formula 15]

[0403] 2 < TTL / CA_max < 5

[0404] In Equation 15, CA_max represents the largest effective diameter (mm) among the object side and sensor side of the plurality of lenses, and TTL (Total track length) represents the distance (mm) along the optical axis (OA) from the vertex of the first surface (S1) of the first lens (101, 201) to the top surface of the image sensor (300). Equation 15 establishes the relationship between the total optical axis length of the optical system and the maximum effective diameter, thereby providing an improved mobile optical system. In the first and second embodiments, Equation 15 preferably satisfies 2.5 < TTL / CA_max < 3.5.

[0405]

[0406] [Mathematical Formula 16]

[0407] 1 < TTL / ImgH < 2

[0408] In Equation 16, TTL (Total track length) refers to the distance (mm) along the optical axis (OA) from the vertex of the first surface (S1) of the first lens (101, 201) to the top surface of the image sensor (300), and ImgH refers to the maximum diagonal length of the image sensor (300). When Equation 16 is satisfied, the optical system (1000, 1100) can have a TTL for application to the mobile image sensor (300), thereby providing improved image quality. If it is below the lower limit of Equation 2, it is necessary to increase the refractive power of the lenses, making it difficult to correct spherical aberration or distortion aberration; if it exceeds the upper limit of Equation 2, the effective aperture or TTL of the lenses becomes longer, which may cause a problem where the imaging lens system becomes larger. In the first and second embodiments, mathematical formula 16 can preferably satisfy 1.5 < TTL / ImgH < 2.

[0409]

[0410] [Mathematical Formula 17]

[0411] 1 < EFL(F) / ImgH < 2

[0412] In Equation 17, EFL(F) is the total effective focal length of the optical system (1000, 1100), and ImgH represents the maximum diagonal length of the image sensor (300). If Equation 17 is satisfied, the mobile image sensor (300) may have improved aberration characteristics in terms of size. In the first and second embodiments, Equation 17 preferably satisfies 1.5 < EFL(F) / ImgH < 2.

[0413]

[0414] [Mathematical Formula 18]

[0415] 0.1 < ΣCT / TTL < 1

[0416] Equation 18 can establish a relationship between the sum of the center thicknesses of the lenses (ΣCT) and the distance (TTL) from the vertex of the first surface (S1) of the first lens (101, 201) to the top surface of the image sensor (300) along the optical axis (OA). If the upper limit of Equation 18 is exceeded, the number of lenses increases, and the movement of the moving lens group in the optical system may become disadvantageous. If the lower limit of Equation 18 is not met, the AF correction performance of the optical system may be degraded. In the first and second embodiments, Equation 18 preferably satisfies 0.1 < ΣCT / TTL < 0.5.

[0417]

[0418] [Mathematical Formula 19]

[0419] 0.1 < ΣCG / TTL < 1

[0420] Equation 19 can establish a relationship between the sum of the gaps between adjacent lenses (ΣCG) and the distance (TTL) from the vertex of the first surface (S1) of the first lens to the upper surface of the image sensor (300) along the optical axis (OA). If the upper limit of Equation 19 is exceeded, the movement distance of the moving lens group in the lens optical system increases, and consequently, the current consumption during AF correction operation may increase. If the lower limit of Equation 19 is not met, the AF correction performance of the optical system may be degraded. In the first and second embodiments, Equation 19 preferably satisfies 0.1 < ΣCG / TTL < 0.5.

[0421]

[0422] [Mathematical Formula 20]

[0423] 2 < ΣCT / ΣCG < 4

[0424] Equation 20 can establish a relationship between the sum of the center thicknesses of the lenses (ΣCT) and the sum of the spacing between adjacent lenses (ΣCT). If the upper limit of Equation 20 is exceeded, the number of lenses increases, and the movement of the moving lens group in the optical system may become disadvantageous. If the lower limit of Equation 20 is not met, AF correction performance may be degraded. In the first and second embodiments, Equation 20 preferably satisfies 2.5 < ΣCT / ΣCG < 3.5.

[0425]

[0426] [Mathematical Formula 21]

[0427] 1 < CA_max / CA_min < 2

[0428] In Equation 21, CA_max represents the maximum effective diameter among the object sides and sensor sides of the lenses, and CA_min represents the minimum effective diameter among the object sides and sensor sides of the lenses. When Equation 21 is satisfied, the optical system can set a size for a slim and compact structure while maintaining optical performance. In the first and second embodiments, Equation 21 preferably satisfies 1 < CA_max / CA_min < 1.5.

[0429]

[0430] [Mathematical Formula 22]

[0431] 0.1 < CA_max / ImgH < 1

[0432] In Equation 22, CA_max represents the maximum effective diameter among the object sides and sensor sides of the lenses, and ImgH represents the maximum diagonal length of the image sensor (300). When Equation 22 is satisfied, the optical system can maintain good optical performance and set a size for a slim and compact structure. In the first and second embodiments, Equation 22 can preferably satisfy 0.3 < CA_max / ImgH < 0.7.

[0433]

[0434] [Mathematical Formula 23]

[0435] 0.1 < CA_min / ImgH < 1

[0436] In Equation 23, CA_min represents the minimum effective diameter among the object sides and sensor sides of the lenses, and ImgH represents the maximum diagonal length of the image sensor (300). When Equation 23 is satisfied, the optical system can maintain good optical performance and set a size for a slim and compact structure. In the first and second embodiments, Equation 23 preferably satisfies 0.1 < CA_min / ImgH < 0.5.

[0437]

[0438] [Mathematical Formula 24]

[0439] 1 < PT1 / PT2 < 1.5

[0440] In Equation 24, PT1 is the thickness on the optical axis (OA) of the first optical path control member (111, 211), and PT2 is the thickness on the optical axis (OA) of the second optical path control member (112, 212). If the value is less than the lower limit of Equation 24, there is a problem of the size of the entire optical system increasing, and if the value exceeds the upper limit, there is a problem of vignetting occurring and the resolution decreasing. In the first and second embodiments, Equation 24 can preferably satisfy 1.2 < PT1 / PT2 < 1.3.

[0441]

[0442] [Mathematical Formula 25]

[0443]

[0444] In Equation 25, Z represents Sag, which can mean the distance in the direction of the optical axis from any position on the aspherical surface to the vertex of the aspherical surface. Y represents the distance in the direction perpendicular to the optical axis from any position on the aspherical surface to the optical axis. c can represent the curvature of the lens, and K can represent the conic constant. Additionally, A, B, C, D, E, and F can represent the aspheric constants.

[0445]

[0446] The optical system (1000, 1100) according to the first and second embodiments may satisfy at least one or two of the mathematical formulas 1 to 25. In this case, the optical system (1000, 1100) may have improved optical characteristics. Specifically, when the optical system (1000, 1100) satisfies at least one or two of the mathematical formulas 1 to 25, the optical system (1000, 1100) may have improved resolution and may improve aberration and distortion characteristics. In addition, the optical system (1000, 1100) may secure a Back Focal Length (BFL) for applying the image sensor (300), compensate for the degradation of optical characteristics due to temperature changes, and minimize the gap between the last lens and the image sensor (300), thereby having good optical performance in the center and periphery of the field of view (FOV).

[0447]

[0448] Mathematical Formula Example 1 Example 2 Example 1 0.5 < TD_LG1 / TD_LG2 < 1.50.9261.101215 < EFL(F) < 1817.06017.06035 < BFL_1 < 107.6109.137440 < Ave_ABV < 6041.51251.31551.5 < Ave_Ind < 1.651.6031.55960.1 < |f_LG1 / f_LG2| < 10.9870.9587(1st Example)1 < LG1_stroke < 2(2nd Example)1 < LG2_stroke < 21.7921.66081 < CA_L1 / CA_L4 < 21.4081.46591 < EFL(F) / F1 < 1.51.0451.098101 < TTL / F1 < 1.51.2071.1841110 < TTL < 2019.69218.396128 < ImgH < 1210.24410.636132 < Fno < 32.7972.797142 < f1 / |L1R1| < 43.1382.987152 < TTL / CA_max < 53.3303.042161 < TTL / ImgH < 21.9221.730171 < EFL(F) / ImgH < 21.6651.604180.1 < ΣCT / TTL < 10.4490.344190.1 < ΣCG / TTL < 10.1390.128202 < ΣCT / ΣCG < 43.2322.692211 < CA_max / CA_min < 21.4081.465220.1 < CA_max / ImgH < 10.5770.569230.1 < CA_min / ImgH < 10.4100.388241 < PT1 / PT2 < 1.51.2501.250

[0449] Table 7 shows the result values ​​for the above-described Equations 1 to 24 in the optical system (1000, 1100) of the embodiment. Referring to Table 7, it can be seen that the optical system (1000, 1100) satisfies at least one, two or more, or three or more of Equations 1 to 24. Specifically, it can be seen that the optical system (1000, 1100) according to the embodiment satisfies all of Equations 1 to 24. Accordingly, the optical system (1000, 1100) can have good optical performance and excellent optical characteristics at the center and periphery of the field of view (FOV).

[0450]

[0451] FIG. 20 is an example of a portable terminal having an optical system according to the present embodiment. As illustrated in FIG. 20, the portable terminal (1500) may include a camera module (1520), a flash module (1530), and an autofocus device (1510) provided on one side or the rear side. Here, the autofocus device (1510) may include a surface-emitting laser element and a light receiver disclosed above as a light-emitting layer.

[0452] The flash module (1530) may include an emitter that emits light inside it. The flash module (1530) may be operated by the camera operation of the mobile terminal or by the control of the user. The camera module (1520) may include an image capturing function and an autofocus function. For example, the camera module (1520) may include an autofocus function using an image.

[0453] The autofocus device (1510) may include an autofocus function using a laser. The autofocus device (1510) may be primarily used under conditions where the autofocus function using the image of the camera module (1520) is degraded. Additionally, although not shown in the drawing, at least one additional camera module may be disposed on the front of the mobile terminal (1500). At least one of the camera modules within the mobile terminal may have the tele-type folded optical system disclosed above.

[0454] An optical system or camera module according to an embodiment of the invention, and a lens assembly according to various embodiments, may be applied to an electronic device employing an image sensor, for example. A lens assembly according to an exemplary embodiment may be applied to various electronic devices such as digital cameras, interchangeable lens cameras, video cameras, mobile phone cameras, cameras for small mobile devices, VR, AR, drones, or manned / unmanned aircraft.

[0455] The features, structures, effects, etc. described in the embodiments above are included in at least one embodiment of the present invention and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, etc. exemplified in each embodiment may be combined or modified and implemented in other embodiments by a person skilled in the art to which the embodiments belong. Therefore, details regarding such combinations and modifications should be interpreted as being included within the scope of the present invention.

[0456] Furthermore, although the invention has been described above with reference to embodiments, this is merely illustrative and does not limit the invention. Those skilled in the art will understand that various modifications and applications not exemplified above are possible within the scope of the essential characteristics of the embodiments. For example, each component specifically shown in the embodiments may be modified and implemented. Differences related to such modifications and applications should be interpreted as being included within the scope of the invention as defined in the appended claims.

Claims

1. Includes first and second lens groups arranged along the optical axis, The above first lens group has a positive (+) refractive power, and The above second lens group has negative (-) refractive power, and An optical system in which the lens positioned closest to the object in the first lens group above has the largest effective aperture.

2. In Paragraph 1, An optical system in which the object side of the lens positioned closest to the object side in the first lens group at the above optical axis has a convex shape.

3. In Paragraph 1, It includes a first light path control member disposed on the object side of the first lens group, and An optical system comprising a second optical path control member disposed on the sensor side of the second lens group.

4. In Paragraph 1, The above first lens group is an optical system comprising a first lens having a positive (+) refractive power, a second lens having a positive (+) refractive power, and a third lens having a negative (-) refractive power.

5. In Paragraph 1, The above second lens group is an optical system comprising a fourth lens having positive (+) refractive power, a fifth lens having negative (-) refractive power, and a sixth lens having positive (+) refractive power.

6. In Paragraph 4, An optical system in which the second lens and the third lens on the above optical axis have a meniscus shape convex toward the sensor side.

7. In Paragraph 4, In the above optical axis, the fourth lens has a shape with both sides convex, and The optical system in which the fifth lens on the above optical axis has a meniscus shape that is convex toward the sensor side.

8. In Paragraph 1, An optical system satisfying the following condition. <Condition> 0.5 < TD_LG1 / TD_LG2 < 1.5 (In the above conditional equation, TD_LG1 is the length of the first lens group in the optical axis direction, and TD_LG2 is the length of the second lens group in the optical axis direction.) 9. In Paragraph 1, An optical system satisfying the following condition. <Condition> 1 < TTL / ImgH < 2 (In the above conditional equation, TTL is the optical axis distance from the vertex of the object side of the first lens to the top plane of the image sensor, and ImgH is the maximum diagonal length of the image sensor.) 10. Includes first to sixth lenses arranged along the optical axis, and The first lens above has a positive (+) refractive power, and The second lens above has a positive (+) refractive power, and The above third lens has a negative (-) refractive power, and The above-mentioned fourth lens has a positive (+) refractive power, and The above fifth lens has a negative (-) refractive power, and The above-mentioned sixth lens has a negative (-) refractive power, and Among the first to sixth lenses on the above optical axis, the thickness of the third lens is the smallest, and An optical system in which the first lens on the above optical axis has a meniscus shape that is convex toward the object.

Images