Optical system and camera module comprising same

Abstract

An optical system according to an embodiment of the present invention comprises: a first lens having positive (+) refractive power; a second lens; and a third lens having negative (-) refractive power, wherein the first to third lenses are sequentially disposed from an object side to an image side and include an aperture disposed between the first lens and the second lens, and the distance between the first lens and the second lens on an optical axis is greater than the thickness of the third lens.

Description

Optical system and camera module including the same

[0001] The present embodiment relates to an optical system having improved optical performance and a camera module including the same.

[0002] ADAS (Advanced Driving Assistance System) is an advanced driver assistance system that assists the driver in driving. It consists of sensing the situation ahead, judging the situation based on the sensed results, and controlling the vehicle's behavior based on the situation judgment. For example, ADAS sensor devices detect a vehicle ahead and recognize lanes. After the target lane, target speed, and forward target are determined, the vehicle's ESC (Electrical Stability Control), EMS (Engine Management System), and MDPS (Motor Driven Power Steering) are controlled. Representative examples of ADAS can be implemented as automatic parking systems, low-speed city driving assistance systems, and blind spot warning systems.

[0003] Sensor devices for detecting the situation ahead in ADAS include GPS sensors, laser scanners, forward radar, Lidar, etc., and the most representative one is a camera for taking pictures of the front, rear, and sides of the vehicle.

[0004] These cameras can be placed outside or inside a vehicle to detect the vehicle's surroundings. Furthermore, the cameras can be placed inside the vehicle to detect the driver and passengers. For example, the camera can photograph the driver from a position adjacent to the driver and detect the driver's health, drowsiness, and drinking status. Furthermore, the camera can photograph the passenger from a position adjacent to the passenger and detect the passenger's sleepiness, health, and other conditions, and provide the driver with information about the passenger.

[0005] In particular, the most crucial element for capturing an image from a camera is the imaging lens that forms the image. Recently, interest in high-performance features such as high image quality and high resolution has been increasing, and research is being conducted on optical systems comprising multiple lenses to achieve these features. However, there is a problem in that the characteristics of the optical system change when the camera is exposed to harsh environments, such as high temperature, low temperature, moisture, or high humidity, either inside or outside the vehicle. In this case, the camera faces the problem of difficulty in uniformly achieving excellent optical and aberration characteristics.

[0006] Furthermore, because vehicle camera modules are exposed to the outside world, image quality can deteriorate due to moisture and temperature. In particular, camera modules have the problem of their optical characteristics changing depending on ambient temperature and lens material.

[0007] Therefore, a new optical system and camera that can solve the above-described problems are required.

[0008] The present embodiment seeks to provide an optical system and camera module with improved optical characteristics.

[0009] In addition, the present embodiment seeks to provide an optical system and camera module capable of providing excellent optical characteristics in low-temperature or high-temperature environments.

[0010] Additionally, the present embodiment seeks to provide an optical system and camera module capable of preventing or minimizing changes in optical properties over a variety of temperature ranges.

[0011] Additionally, the present embodiment can provide a camera system capable of predicting and compensating for changes in the focal length of a lens within a camera module.

[0012] Additionally, the present embodiment can provide a camera system capable of predicting a temperature change of at least one lens within a camera module and adjusting an optical axis distance.

[0013] Additionally, the present embodiment can provide a control system for controlling a camera module applied to a device or structure subject to large temperature changes.

[0014] In order to solve the above technical problem, an optical system according to the present embodiment includes a first lens having positive (+) refractive power; a second lens; and a third lens having negative (-) refractive power, wherein the first to third lenses are sequentially arranged from an object side to an image side, and an aperture is arranged between the first lens and the second lens, and a distance between the first lens and the second lens on the optical axis is greater than a thickness of the third lens.

[0015] In order to solve the above technical problem, an optical system according to another embodiment of the present invention includes a first lens having positive (+) refractive power; a second lens having negative (-) refractive power; and a third lens having positive (+) refractive power, wherein the first to third lenses are sequentially arranged from an object side to an image side, and an aperture is arranged between the first lens and the second lens, and a thickness of the third lens on the optical axis is greater than a thickness of the first lens.

[0016] In the above optical axis, the third lens may have a meniscus shape convex toward the object side.

[0017] In the above optical axis, the second lens may have a convex meniscus shape toward the sensor.

[0018] The distance between the first lens and the second lens on the optical axis may be greater than the distance between the second lens and the third lens.

[0019] The thickness of the second lens on the optical axis may be greater than the gap between the second lens and the third lens.

[0020] The following condition can be satisfied. <Condition> 3 < f < 5 (In the above condition, f means the total focal length of the optical system.)

[0021] The following condition can be satisfied. <Condition> 1.8 < Fno < 2.2 (In the above condition, Fno means the F-number of the optical system.)

[0022] The following condition can be satisfied. <Condition> 1.5 < n1 < 1.6 (In the above condition, n1 means the refractive index of the first lens.)

[0023] The following condition can be satisfied. <Condition> 20 < v1 < 30 (In the above condition, v1 means the Abbe number of the first lens.)

[0024] The following condition can be satisfied. <Condition> 0.1 < |f1 / f2| < 1.5 (In the above condition, f1 is the focal length of the first lens, and f2 is the focal length of the second lens.)

[0025] The following condition can be satisfied. <Condition> 5 < TTL < 6 (In the above condition, TTL means the optical axis distance from the object side of the first lens to the image sensor.)

[0026] The following condition can be satisfied. <Condition> 40 < FOV < 60 (In the above condition, FOV means the angle of view in the optical system.)

[0027] The optical system and camera module according to the present embodiment can have improved optical characteristics.

[0028] In detail, in the optical system according to the present embodiment, the plurality of lenses may have set shapes, refractive powers, focal lengths, thicknesses, etc., and thus may have improved distortion and aberration characteristics. Accordingly, the optical system and camera module according to the embodiment may provide high-resolution, high-quality images within a set angle of view range.

[0029] In addition, the optical system and camera module according to the present embodiment can operate in various temperature ranges. Specifically, the optical system can include first to third lenses made of a plastic material. In this case, each of the first to third lenses can have a set refractive power. Accordingly, even when the focal length of each lens changes due to a change in refractive index according to a change in temperature, the first to third lenses can compensate for each other. That is, the optical system can effectively perform refractive power distribution in a temperature range of low temperature (about -40°C) to high temperature (about 85°C), and can prevent or minimize changes in optical characteristics in a temperature range of low temperature (about -40°C) to high temperature (85°C). Therefore, the optical system and camera module according to the present embodiment can maintain improved optical characteristics in various temperature ranges.

[0030] Additionally, it is possible to compensate for changes in the back focal length (BFL) within the camera module. Furthermore, by shifting at least one lens along the optical axis in response to temperature changes, performance changes can be minimized. Furthermore, ambient temperature information for the camera module can be detected from internal or external devices within the vehicle, and the distance between at least one lens and the sensor can be adjusted within a predictable range for each temperature. Consequently, performance changes due to temperature changes in the camera module can be minimized.

[0031] Furthermore, the optical system and camera module according to the present embodiment can achieve excellent optical characteristics while satisfying the minimum angle of view set by the lens. This allows the optical system to be provided with a slimmer and more compact structure. Accordingly, the optical system and camera module can be used in various applications and devices, and can exhibit excellent optical characteristics even in harsh temperature environments, such as high-temperature vehicle interiors during the summer.

[0032] FIG. 1 is a drawing showing a plan view of a vehicle to which a camera module or optical system according to the present embodiment is applied.

[0033] FIG. 2 and FIG. 3 are drawings illustrating the interior of a vehicle to which a camera module or optical system according to the present embodiment is applied.

[0034] Figure 4 is a configuration diagram of an optical system according to the first embodiment.

[0035] Figure 5 is a graph of the diffraction MTF characteristics of the optical system of the first embodiment in a low-temperature (-40°C) environment.

[0036] Fig. 6 is a graph of the diffraction MTF characteristics of the optical system of the first embodiment in which the peak reference is compensated according to actuator operation in a low-temperature (-40°C) environment.

[0037] Figure 7 is a graph of the aberration diagram of the optical system of the first embodiment in a low-temperature (-40°C) environment.

[0038] Figure 8 is a graph of the diffraction MTF characteristics of the optical system of the first embodiment in a room temperature (20°C) environment.

[0039] Fig. 9 is a graph of the diffraction MTF characteristics of the optical system of the first embodiment in which the peak reference is compensated according to actuator operation in a room temperature (20°C) environment.

[0040] Figure 10 is a graph of the aberration diagram of the optical system of the first embodiment in a room temperature (20°C) environment.

[0041] Figure 11 is a graph of the diffraction MTF characteristics of the optical system of the first embodiment in a high temperature (85°C) environment.

[0042] Fig. 12 is a graph of the diffraction MTF characteristics of the optical system of the first embodiment in which the peak reference is compensated according to actuator operation in a high temperature (85°C) environment.

[0043] Figure 13 is a graph of the aberration diagram of the optical system of the first embodiment in a high temperature (85°C) environment.

[0044] Figure 14 is a configuration diagram of an optical system according to the second embodiment.

[0045] Figure 15 is a graph of the diffraction MTF characteristics of the optical system of the second embodiment in a low-temperature (-40°C) environment.

[0046] Fig. 16 is a graph of the diffraction MTF characteristics of the optical system of the second embodiment in which the peak reference is compensated according to actuator operation in a low-temperature (-40°C) environment.

[0047] Figure 17 is a graph of the aberration diagram of the optical system of the second embodiment in a low-temperature (-40°C) environment.

[0048] Figure 18 is a graph of the diffraction MTF characteristics of the optical system of the second embodiment in a room temperature (20°C) environment.

[0049] Fig. 19 is a graph of the diffraction MTF characteristics of the optical system of the second embodiment in which the peak reference is compensated according to actuator operation in a room temperature (20°C) environment.

[0050] Figure 20 is a graph of the aberration diagram of the optical system of the second embodiment in a room temperature (20°C) environment.

[0051] Figure 21 is a graph of the diffraction MTF characteristics of the optical system of the second embodiment in a high temperature (85°C) environment.

[0052] Fig. 22 is a graph of the diffraction MTF characteristics of the optical system of the second embodiment in which the peak reference is compensated according to actuator operation in a high temperature (85°C) environment.

[0053] Figure 23 is a graph of the aberration diagram of the optical system of the second embodiment in a high temperature (85°C) environment.

[0054] Figure 24 is a drawing showing a camera system of the present embodiment.

[0055] Figures 25 (A) and (B) are drawings explaining the change in focal length of a lens according to temperature within a camera module.

[0056] Fig. 26 is a side cross-sectional view showing an example of a camera module in the camera system of the present embodiment.

[0057] Figure 27 is a table showing the lens correction ratio according to the temperature stored in the storage unit of the camera system of the present embodiment.

[0058] Figure 28 is a graph showing the lens correction ratio according to temperature in the camera system of the present embodiment.

[0059] Fig. 29 is a diagram showing a table showing a temperature compensation rate according to a reference BFL stored in a storage unit of the camera system of the present embodiment.

[0060] Figure 30 is a graph showing a method for compensating focal length according to temperature in the camera system of the present embodiment.

[0061] Figure 31 is a schematic diagram for explaining some terms in the optical system according to the present embodiment.

[0062] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0063] However, the technical idea of ​​the present invention is not limited to some of the embodiments described, but can be implemented in various different forms, and within the scope of the technical idea of ​​the present invention, one or more of the components between the embodiments can be selectively combined or substituted for use.

[0064] In addition, terms (including technical and scientific terms) used in this embodiment may be interpreted as having a meaning that can be generally understood by a person of ordinary skill in the technical field to which this embodiment belongs, unless explicitly and specifically defined and described, and terms that are commonly used, such as terms defined in a dictionary, may be interpreted in consideration of the contextual meaning of the relevant technology.

[0065] Additionally, the terms used in this embodiment are for the purpose of describing the embodiments and are not intended to limit the present invention.

[0066] In this specification, the singular may also include the plural unless specifically stated otherwise in the phrase, and when it is described as “A and / or at least one (or more) of B, C”, it may include one or more of all combinations that can be combined with A, B, C.

[0067] Additionally, in describing the components of this embodiment, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only intended to distinguish the components from other components, and are not intended to limit the nature, order, or sequence of the components.

[0068] And, when a component is described as being 'connected', 'coupled', or 'connected' to another component, it may include not only cases where the component is 'connected', 'coupled', or 'connected' directly to the other component, but also cases where the component is 'connected', 'coupled', or 'connected' by another component between the component and the other component.

[0069] Additionally, when described as being formed or arranged "above" or "below" each component, "above" or "below" includes not only cases where the two components are in direct contact with each other, but also cases where one or more other components are formed or arranged between the two components. Furthermore, when expressed as "above" or "below," the meaning may include not only the upward direction but also the downward direction based on one component.

[0070] Additionally, a convex surface of a lens may mean that the lens surface in the optical axis region has a convex shape, and a concave surface of a lens may mean that the lens surface in the optical axis region has a concave shape.

[0071] Additionally, the "object side" may refer to the side of the lens facing the object side based on the optical axis, and the "sensor side" may refer to the side of the lens facing the image sensor based on the optical axis. The "object side" may be the "water side." The "sensor side" may be the "image side."

[0072] Additionally, the vertical direction may mean a direction perpendicular to the optical axis, and the end of the lens or lens surface may mean the extreme end of the effective area of ​​the lens through which incident light passes.

[0073] Additionally, the central thickness of the lens may refer to the length in the direction of the optical axis between the object side and the sensor side of the lens.

[0074] Additionally, 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.

[0075] Additionally, in the embodiment, low temperature may mean a specific temperature (-40°C) or a temperature range of about -40°C to about 30°C, and room temperature may mean a specific temperature (20°C) or a temperature range of about 18°C ​​to about 30°C. Additionally, high temperature may mean a specific temperature (85°C) or a temperature range of about 80°C to about 105°C.

[0076]

[0077] FIG. 1 is a drawing showing a plan view of a vehicle to which a camera module or optical system according to the present embodiment is applied, and FIGS. 2 and 3 are drawings showing the interior of a vehicle to which a camera module or optical system according to the present embodiment is applied.

[0078] First, referring to FIG. 1, the vehicle camera system according to the present embodiment includes an image generation unit (2110), a first information generation unit (2120), a second information generation unit (2210, 2220, 2230, 2240, 2250, 2260), and a control unit (2140).

[0079] The image generation unit (2110) may include at least one first camera module (2310) disposed outside or inside the vehicle (2000) and may generate a front image of the vehicle (2000). In addition, the image generation unit (2110) may capture not only the front of the vehicle (2000) but also the surroundings of the vehicle (2000) in one or more directions using the first camera module (2310) to generate an image of the surroundings of the vehicle (2000). Here, the front image and the surrounding images may be digital images and may include color images, black and white images, and infrared images. In addition, the front image and the surrounding images may include still images and moving images. The image generation unit (2110) may provide the front image and the surrounding images to the control unit (2140).

[0080] Next, the first information generating unit (2120) may include at least one radar and / or camera placed in the vehicle (2000), and detects the front of the vehicle (2000) to generate first detection information. Specifically, the first information generating unit (2120) may be placed in the vehicle (2000), and generate first detection information by detecting the position and speed of vehicles (2000) located in front of the vehicle (2000), the presence and position of pedestrians, etc.

[0081] By using the first detection information generated by the first information generation unit (2120), the distance between the vehicle (2000) and the vehicle in front can be controlled to be maintained at a constant level, and the driving stability of the vehicle (2000) can be improved in specific preset cases, such as when the driver wants to change the driving lane of the vehicle (2000) or when parking in reverse. The first information generation unit (2120) can provide the first detection information to the control unit (2140).

[0082] Next, the second information generation unit (2210, 2220, 2230, 2240, 2250, 2260) detects each side of the vehicle (2000) and generates second detection information based on the front image generated by the image generation unit (2110) and the first detection information generated by the first information generation unit (2120). Specifically, the second information generation unit (2210, 2220, 2230, 2240, 2250, 2260) may include at least one radar and / or camera disposed in the vehicle (2000), and may detect the position and speed of vehicles located on the side of the vehicle (2000) or capture images. Here, the second information generation units (2210, 2220, 2230, 2240, 2250, 2260) can be placed at the front two corners, side mirrors, and rear center and rear two corners of the vehicle (2000), respectively.

[0083]

[0084] In addition, referring to FIGS. 2 and 3, the image generation unit (2110) may include at least one second camera module (2320) disposed inside the vehicle (2000). The second camera module (2320) may be disposed adjacent to the driver and passengers. For example, the second camera module (2320) may be disposed at a position spaced apart from the driver and passengers by a first distance (d1) to generate an interior image of the vehicle (2000). At this time, the first distance (d1) may be about 500 mm or more. In detail, the first distance (d1) may be about 600 mm or more. In addition, the second camera module (2320) may have a field of view (FOV) of about 55 degrees or more.

[0085] The image generation unit (2110) can capture images of the driver and / or passengers inside the vehicle (2000) using the second camera module (2320) to generate an interior image of the vehicle (2000). Here, the interior image of the vehicle may be a digital image, and may include color images, black and white images, infrared images, etc. In addition, the interior image may include still images and moving images. The image generation unit (2110) provides the interior image of the vehicle (2000) to the control unit (2140).

[0086] The control unit (2140) can provide information to the passengers of the vehicle (2000) based on the information provided from the image generation unit (2110). For example, the control unit (2140) can detect the driver's health status, drowsiness, drinking status, etc. based on the information provided from the image generation unit (2110), and can provide the driver with corresponding information such as guidance and warnings. In addition, the control unit (2140) can detect the passenger's sleep status, health status, etc. based on the information provided from the image generation unit (2110), and can provide the driver and / or passengers with information about this.

[0087] Such a vehicle camera system may include a camera module having an optical system (1000) according to the following exemplary embodiment, and may provide or process information acquired through the front, rear, each side, or corner area of ​​the vehicle (2000) to a user to enable autonomous driving or protect the vehicle (2000) and objects from surrounding safety. In addition, the camera system may be placed inside the vehicle (2000) to provide various information to the driver and passengers. That is, at least one camera module among the first camera module (2310) and the second camera module (2320) may include the optical system (1000) described below.

[0088] The camera module according to this embodiment can be installed in multiple units within a vehicle to enhance safety regulations, enhance autonomous driving functions, and increase convenience. Furthermore, the optical system of the camera module is used as a component for controlling systems such as the Lane Keeping Assistance System (LKAS), Lane Departure Warning System (LDWS), and Driver Monitoring System (DMS). These vehicle camera modules can achieve stable optical performance even under ambient temperature changes and offer competitive pricing, thereby ensuring the reliability of vehicle components.

[0089]

[0090] Hereinafter, the optical systems according to the first and second embodiments will be described in detail.

[0091] The optical system (1000, 1500) according to the first and second embodiments may include a plurality of lenses (100) and an image sensor (600). In detail, the optical system (1000, 1500) according to the first and second embodiments may include two or more lenses. For example, the optical system (1000, 1500) may include three lenses, and may include a first lens (100), a second lens (200), a third lens (300), and an image sensor (600) that are sequentially arranged from the object side to the sensor side. The first to third lenses (100, 200, 300) may be sequentially arranged along the optical axis (OA) of the optical system (1000, 1500).

[0092] In this case, light corresponding to information about the object can pass through the first lens (100), the second lens (200), and the third lens (300) and enter the image sensor (600).

[0093] Each of the plurality of lenses (100) may include an effective area and an ineffective area. The effective area may be an area through which light incident on each of the first to third lenses (100, 200, 300) passes. In other words, the effective area may be an area in which the incident light is refracted to implement optical characteristics. The effective area may be an effective diaphragm area.

[0094] The inactive area may be located around the active area. The inactive area may be an area where no light enters. In other words, the inactive area may be an area unrelated to optical properties. Furthermore, the inactive area may be an area fixed to a barrel (not shown) that accommodates the lens. The inactive area may be a non-optical area.

[0095] The image sensor (600) can detect light. Specifically, the image sensor (600) can detect light that has sequentially passed through a plurality of lenses, specifically the first to third lenses (100, 200, 300). The image sensor (600) can include an element capable of detecting incident light, such as a charge-coupled device (CCD) or a complementary metal oxide semiconductor (CMOS).

[0096] The image sensor (600) may include a plurality of pixels having a set size. For example, the pixel size of the image sensor (600) may be about 3 μm. The image sensor (600) may detect light of a set wavelength. For example, the image sensor (600) may detect infrared (IR) light. Specifically, the image sensor (600) may detect near infrared ray light of about 1500 nm or less. For example, the image sensor may detect light in a wavelength band of about 880 nm to about 1000 nm.

[0097] The optical system (1000, 1500) according to the first and second embodiments may further include a cover glass (500) and a filter (400).

[0098] A cover glass (500) may be placed between a plurality of lenses (100, 200, 300) and an image sensor (600). The cover glass (500) may be placed adjacent to the image sensor (600). The cover glass (500) may have a shape corresponding to the image sensor (600). The cover glass (500) may be provided with a size larger than or equal to the image sensor (600) to protect the upper portion of the image sensor (600).

[0099] Additionally, the filter (400) may be placed between the plurality of lenses (100, 200, 300) and the image sensor (600). The filter (400) may be placed between the last lens (third lens (300)) that is closest to the image sensor (600) among the plurality of lenses (100, 200, 300) and the image sensor (600). In detail, the filter (400) may be placed between the last lens (third lens (300)) and the cover glass (500).

[0100] The filter (400) can pass light of a set wavelength band and filter out light of a different wavelength band. The filter (400) can pass light of a wavelength band corresponding to the light received by the image sensor (600) and block light of a wavelength band that does not correspond to the light received. Specifically, the filter (400) can pass light of an infrared wavelength band and block light of an ultraviolet ray and a visible light band. For example, the filter (400) can include at least one of an infrared pass (IR Pass) filter and an infrared cutoff (IR Cutoff) filter.

[0101] The optical system (1000, 1500) according to the first and second embodiments may include an aperture (STOP). The aperture (STOP) may be arranged between the first lens (100) and the second lens (200). The aperture (STOP) may be arranged closer to the first lens (100) than to the second lens (200). The aperture (STOP) may be spaced apart from the object-side surface of the second lens (200). The aperture (STOP) may control the amount of light incident from a subject. The aperture (STOP) may control the amount of light passing through the first lens (100). The aperture (STOP) may control the amount of light incident to the third lens (300). The aperture (STOP) may include an aperture stop.

[0102]

[0103] Hereinafter, with reference to Table 1, a plurality of lenses according to the first embodiment will be described in more detail.

[0104] Lens surface curvature radius (mm) thickness or gap (mm) refractive index Abbe number effective diameter size first lens surface 1 (S1) 2.138 1.233 1.58 50 26.0000 2.552 second surface (S2) -18.704 0.050 1.866 STOP-infinity 0.69 21.640 second lens surface 3 (S3) -1.824 1.145 1.58 50 26.0000 1.849 fourth surface (S4) -1.058 0.050 2.524 third lens surface 5 (S5) 142.067 0.700 1.58 50 26.0000 2.904 sixth surface (S6) 1.330 0.172 3.774 filter infinity 0.300 3.919 Infinity0.6004.029 cover glass, Infinity0.4004.367 image sensor, Infinity0.0504.542

[0105] Table 1 shows the radius of curvature of the first to third lenses (100, 200, 300) according to the first embodiment, the thickness of each lens on the optical axis (OA), the distance between each lens on the optical axis (OA), the refractive index for light in the d-line (587.562 mm) wavelength band, the Abbe's Number, and the size of the clear aperture (CA). Here, the lens data described in Table 1 is data at room temperature (about 20°C). Referring to FIG. 4 and Table 1, the first lens (100) of the optical system (1000) according to the first embodiment may be made of a plastic material and may have positive (+) refractive power on the optical axis (OA).

[0106] The first surface (S1) on the object side of the first lens (100) on the optical axis (OA) may have a convex shape, and the second surface (S2) on the sensor side may have a convex shape. The first lens (100) may have a convex shape on both sides on the optical axis (OA). At least one of the first surface (S1) and the second surface (S2) may be an aspherical surface (Asphere). For example, both the first surface (S1) and the second surface (S2) may be aspherical surfaces (Asphere).

[0107] The second lens (200) may have positive (+) or negative (-) refractive power on the optical axis (OA). The second lens (200) may have positive (+) refractive power on the optical axis (OA). The second lens (200) may be made of a plastic material.

[0108] The third surface (S3) on the object side of the second lens (200) on the optical axis (OA) may have a concave shape, and the fourth surface (S4) on the sensor side may have a convex shape. The second lens (200) may have a concave meniscus shape on the object side on the optical axis (OA). The second lens (200) may have a convex meniscus shape on the sensor side on the optical axis (OA). At least one of the third surface (S3) and the fourth surface (S4) may be an aspherical surface (Asphere). For example, both the third surface (S3) and the fourth surface (S4) may be aspherical surfaces (Asphere).

[0109] The third lens (300) may have positive (+) or negative (-) refractive power on the optical axis (OA). The third lens (300) may have negative (-) refractive power on the optical axis (OA). The third lens (300) may be made of a plastic material.

[0110] The object-side fifth surface (S5) of the third lens (300) on the optical axis (OA) may have a convex shape, and the sixth surface (S6) may be concave. The third lens (300) may have a meniscus shape that is convex from the optical axis (OA) toward the object side. Alternatively, the fifth surface (S5) may have a convex shape from the optical axis (OA), and the sixth surface (S6) may be convex from the optical axis (OA). That is, the third lens (300) may have a biconvex shape from the optical axis (OA). Alternatively, the fifth surface (S5) may have a concave shape from the optical axis (OA), and the sixth surface (S6) may be convex from the optical axis (OA). That is, the third lens (300) may have a meniscus shape that is convex from the optical axis (OA) toward the sensor side. In contrast, the fifth surface (S5) may have a concave shape in the optical axis (OA), and the sixth surface (S6) may be concave in the optical axis (OA). That is, the third lens (300) may have a concave shape on both sides in the optical axis (OA).

[0111] At least one of the fifth surface (S5) and the sixth surface (S6) may be an aspherical surface (Asphere). For example, both the fifth surface (S5) and the sixth surface (S6) may be aspherical surfaces (Asphere). The fifth surface (S5) may include at least one inflection point. The fifth surface (S5) may include at least one inflection point in a flange region outside the effective diameter region. The sixth surface (S6) may include at least one inflection point. The sixth surface (S6) may include at least one inflection point within the effective diameter region.

[0112]

[0113] Table 2 below shows Sag data according to the vertical height (0.2 mm interval) of the optical axis (OA) of each of the object side (first surface (S1)) and sensor side (second surface (S2)) of the first lens (100) at room temperature (approximately 20°C).

[0114] In addition, Table 3 is data on lens thickness according to the vertical height (0.2 mm interval) of the optical axis (OA) at room temperature (approximately 20°C). In detail, D_1 in Table 3 is the center thickness of the first lens (100), which is the thickness (mm) at the optical axis (OA) of the first lens (100). In addition, D_1_ET in Table 3 means the thickness (mm) in the optical axis (OA) direction at the end of the effective area of ​​the first lens (100). In detail, it means the distance (mm) in the optical axis (OA) direction between the end of the effective area of ​​the object-side surface (first surface (S1)) of the first lens (100) and the end of the effective area of ​​the sensor-side surface (second surface (S2)) of the first lens (100).

[0115]

[0116] Vertical height of the optical axis from the optical axis on the object side of the first lens (mm) Sag of the object side of the first lens (mm) Vertical height of the optical axis from the optical axis on the sensor side of the first lens (mm) Sag of the sensor side of the first lens (mm) 00000.20.0093630.2-0.0011140.40.0375110.4-0.0050450.60.0844950.6-0.0138990.80.1499350.8-0.0321721.00.2315981.0-0.0671311.20.319758--

[0117] Vertical height of the optical axis from the optical axis (mm) Thickness of the first lens in the optical axis direction (mm) 01.23264 (D_1) 0.21.22217 0.41.19009 0.61.13425 0.81.050541.00.9339 11.20.80056 (D_1_ET)

[0118] Vertical height of the optical axis from the optical axis (mm) Slope angle (degree) of the object side (first surface (S1)) of the first lens Slope angle (degree) of the sensor side (second surface (S2)) of the first lens 00.00.00.25.00.00.410.0-1.00.615.0-3.00.820.0-7.01.023.0-12.01.222.0-

[0119] Referring to Tables 2 and 3, the thickness of the first lens (100) in the direction of the optical axis (OA) may become thinner as it goes from the optical axis (OA) toward the end of the effective diameter of the first lens (100). In addition, Table 4 shows data on the Slope Angle (degree) of the object-side surface (first surface (S1)) of the first lens and the sensor-side surface (second surface (S2)) of the first lens according to the vertical height (0.2 mm interval) of the optical axis (OA) at room temperature (approximately 20°C). The Slope Angle refers to the angle formed by the tangent line touching the lens surface and the line perpendicular to the optical axis (OA). Accordingly, the first lens (100) may have improved aberration control characteristics by controlling incident light.

[0120]

[0121] Table 5 below shows Sag data according to the vertical height (0.2 mm interval) of the optical axis (OA) of each of the object side (third side (S3)) and sensor side (fourth side (S4)) of the second lens (200) at room temperature (approximately 20°C).

[0122] In addition, Table 6 is data on lens thickness according to the vertical height (0.2 mm interval) of the optical axis (OA) at room temperature (approximately 20°C). In detail, D_2 in Table 6 is the center thickness of the second lens (200), which is the thickness (mm) at the optical axis (OA) of the second lens (200). In addition, D_2_ET in Table 6 means the thickness (mm) in the optical axis (OA) direction at the end of the effective area of ​​the second lens (200). In detail, it means the distance (mm) in the optical axis (OA) direction between the end of the effective area of ​​the object-side surface (third surface (S3)) of the second lens (200) and the end of the effective area of ​​the sensor-side surface (fourth surface (S4)) of the second lens (200).

[0123]

[0124] Vertical height of the optical axis from the optical axis on the object side of the second lens (mm)Sag of the object side of the second lens (mm)Vertical height of the optical axis from the optical axis on the sensor side of the second lens (mm)Sag of the sensor side of the second lens (mm)00000.2-0.0110450.2-0.0188660.4-0.0452830.4-0.0743770.6-0.1059320.6-0.1610470.8-0.1949960.8-0.2688241.0-0.3095511.0-0.381872--1.2-0.462742

[0125] Vertical height of the optical axis from the optical axis (mm) Thickness of the second lens in the optical axis direction (mm) 01.14519 (D_2) 0.2 1.137 37 0.4 1.116 10.6 1.09 0 0 8 0.8 1.07 136 (D_2_ET)

[0126] Vertical height of the optical axis from the optical axis (mm) Slope angle (degree) of the object side (third surface (S3)) of the second lens Slope angle (degree) of the sensor side (fourth surface (S4)) of the second lens 00.00.00.2-6.0-10.00.4-13.0-19.00.6-20.0-26.00.8-27.0-29.01.0-33.0-25.01.2--6.0

[0127] Referring to Tables 5 and 6, the thickness of the second lens (200) in the direction of the optical axis (OA) may become thinner as it goes from the optical axis (OA) toward the end of the effective diameter of the second lens (200). In addition, Table 7 shows data on the Slope Angle (degree) of the object-side surface (third surface (S3)) of the second lens (200) and the sensor-side surface (fourth surface (S4)) of the second lens (200) according to the vertical height (0.2 mm interval) of the optical axis (OA) at room temperature (approximately 20°C). The Slope Angle refers to the angle formed by the tangent line touching the lens surface and the line perpendicular to the optical axis (OA). Accordingly, the second lens (200) can prevent or minimize changes in optical characteristics depending on temperature in a temperature range from low to high temperature.

[0128]

[0129] Table 8 below shows Sag data according to the vertical height (0.2 mm interval) of the optical axis (OA) of each of the object side (fifth side (S5)) and sensor side (sixth side (S6)) of the third lens (300) at room temperature (approximately 20°C).

[0130] In addition, Table 9 is data on lens thickness according to the vertical height of the optical axis (OA) at room temperature (approximately 20°C). In detail, D_3 in Table 9 is the center thickness of the third lens (300), which is the thickness (mm) at the optical axis (OA) of the third lens (300). In addition, D_3_ET in Table 9 means the thickness (mm) in the optical axis (OA) direction at the end of the effective area of ​​the third lens (300). In detail, it means the distance (mm) in the optical axis (OA) direction between the end of the effective area of ​​the object-side surface (the fifth surface (S5)) of the third lens (300) and the end of the effective area of ​​the sensor-side surface (the sixth surface (S6)) of the third lens (300).

[0131]

[0132] Vertical height of the optical axis from the optical axis on the object side of the third lens (mm) Sag of the object side of the third lens (mm) Vertical height of the optical axis from the optical axis on the sensor side of the third lens (mm) Sensor side of the third lens Sag(mm)00000.2-0.0003540.20.0142510.4-0.005730.40.049460.6-0.0217250.60.0915740.8-0.0492050.80.1300 781.0-0.088451.00.1582991.2-0.140281.20.1700191.4-0.2064291.40.1573251.6-1.60.107441.8-1.8-0.004427

[0133] Vertical height of the optical axis from the optical axis (mm) Thickness of the third lens in the optical axis direction (mm) 0 0.7 (D_3) 0.2 0.7 146 10.4 0.75 5 19 0.6 0.8 13 30.8 0.8 7 9 28 1.0 0.9 46 7 5 1.21 01 03 1.4 1.0 6 37 5 (D_3_ET)

[0134] Vertical height of the optical axis from the optical axis (mm) Slope angle (degree) of the object side (fifth surface (S5)) of the third lens Slope angle (degree) of the sensor side (sixth surface (S6)) of the third lens 0000.207.00.4-2.011.00.6-6.011.00.8-9.09.01.0-12.06.01.2-16.00.01.4-19.0-8.01.6--20.01.8--37.0

[0135] Referring to Tables 8 and 9, the thickness of the third lens (300) in the direction of the optical axis (OA) may become thicker as it goes from the optical axis (OA) toward the end of the effective diameter of the third lens (300). In addition, Table 10 shows data on the Slope Angle (degree) of the object-side surface (fifth surface (S5)) of the third lens (300) and the sensor-side surface (sixth surface (S6)) of the third lens (300) according to the vertical height (0.2 mm interval) of the optical axis (OA) at room temperature (approximately 20°C). The Slope Angle refers to the angle formed by the tangent line touching the lens surface and the line perpendicular to the optical axis (OA). Accordingly, the third lens (300) can prevent or minimize changes in optical characteristics depending on temperature in a temperature range from low to high temperature.

[0136]

[0137] The values ​​of the aspherical coefficients of each lens surface in the optical system (1000) according to the first embodiment are as shown in Table 11 below.

[0138]

[0139] 1st side (S1) 2nd side (S2) 3rd side (S3) 4th side (S4) 5th side (S5) 6th side (S6) Y2.1376-18.7035-1.8236-1.0579142.06731.3298K0.049279.22191.5921-0.767290.0500-8.0378A-0.0091-0.02550.00890.0394-0.3356-0.1519B-0.0082-0.0211-0.09280.27820.69560.1563C0.00310.020 40.3643-0.4551-0.9699-0.1296D-0.0034-0.0255-0.43840.35510.87900.0719E0.01300.2984-0.0555-0.5115-0.0266F0.0000 -0.0768-0.09150.18650.0064G0.00005.84E-02-4.06E-02-9.72E-04H0.0000-1.08E-024.80E-038.27E-05J-2.35E-04-3.00E-06

[0140] In addition, the distance (first distance) between the first lens (100) and the second lens (200) in the optical system (1000) according to the first embodiment may be as shown in Table 12 below at room temperature (approximately 20°C).

[0141] The vertical height of the optical axis from the optical axis on the sensor side of the first lens (mm) The distance in the optical axis direction from the sensor side of the first lens to the object side of the aperture (mm) The distance in the optical axis direction from the sensor side of the aperture to the object side of the second lens (mm) The vertical height of the optical axis from the optical axis on the object side of the second lens (mm) 0 0.05 0.69 19 9 0 0.20 05 1 1 0.68 0 9 5 0.20 4 0.05 5 0 4 0.64 6 7 1 0.40 6 0.06 3 9 0.58 6 0 6 0.60 8 (L1) 0.08 2 1 7 0.49 7 0.8 (L1)

[0142] Referring to Table 12, the first gap (d12) may refer to the distance in the optical axis direction from the sensor side of the first lens (100) to the object side of the second lens (200). The first gap (d12) may be the sum of the distance in the optical axis direction from the sensor side of the first lens (100) to the object side of the aperture and the distance in the optical axis direction from the sensor side of the aperture to the object side of the second lens (200). The first gap (d12) may be a first air gap (d12). The first gap may become smaller as it goes from the optical axis (OA) to the first point (L1), which is the end of the effective diameter of the second surface (S2). Here, the value indicated by the first point (L1) is an approximate value of the effective radius of the second surface (S2) having a smaller effective diameter among the sensor side (second surface (S2)) of the first lens (100) and the object side (third surface (S3)) of the second lens (200) facing each other, and means an approximate value of 1 / 2 of the effective diameter value of the second surface (S2) described in Table 2.

[0143] The first interval may have a minimum value at the optical axis (OA) and a maximum value at the first point (L1). The maximum value of the first interval may be about 1 to about 2 times the minimum value. For example, in the first embodiment, the maximum value of the first interval may be about 1.64 times the minimum value.

[0144]

[0145] In addition, the distance (second distance) between the second lens (200) and the third lens (300) in the optical system (1000) according to the first embodiment may be as shown in Table 13 below at room temperature (approximately 20°C).

[0146]

[0147] Vertical height of the optical axis from the optical axis on the sensor side of the second lens (mm) Optical axis direction spacing of the second air gap (d23) (mm) (Second spacing) Vertical height of the optical axis from the optical axis on the object side of the third lens (mm) 0 0.70 0.20 71 46 10.20 40.75 5 19 0.40 60.81 33 0.60 80.87 9 28 0.81 00.94 67 5 1.0 1.2 (L2) 1.0 10 3 1.2 (L2)

[0148] Referring to Table 13, the second gap (d23) may refer to the direction of the optical axis from the sensor side of the second lens to the object side of the third lens. The second gap (d23) may be a second air gap (d23). The second gap may increase from the optical axis (OA) to the second point (L2), which is the end of the effective diameter of the fourth surface (S4). Here, the value referred to by the second point (L2) is an approximate value of the effective radius value of the fourth surface (S4) having a smaller effective diameter among the sensor side (fourth surface (S4)) of the second lens (200) and the object side (fifth surface (S5)) of the third lens (300) that face each other, and refers to an approximate value of half of the effective diameter value of the fourth surface (S4) described in Table 2.

[0149] The second interval may have a maximum value at the second point (L2) and a minimum value at the optical axis (OA). The maximum value of the second interval may be about 1 to about 2 times the minimum value. For example, in the first embodiment, the maximum value of the second interval may be about 1.44 times the minimum value.

[0150]

[0151] Figures 5 to 13 are graphs of the diffraction MTF characteristics and aberration of the optical system (1000) according to temperature.

[0152] In detail, FIG. 5 is a graph of the diffraction MTF characteristics of an optical system (1000) in a low temperature (-40°C) environment, and FIG. 6 is a graph of the diffraction MTF characteristics of an optical system (1000) in which the peak reference is compensated according to actuator operation in a low temperature (-40°C) environment. FIG. 8 is a graph of the diffraction MTF characteristics of an optical system (1000) in a room temperature (20°C) environment, and FIG. 9 is a graph of the diffraction MTF characteristics of an optical system (1000) in which the peak reference is compensated according to actuator operation in a room temperature (20°C) environment. Fig. 11 is a graph of the diffraction MTF characteristics of an optical system (1000) in a high temperature (85°C) environment, and Fig. 12 is a graph of the diffraction MTF characteristics of an optical system (1000) in which the peak reference is compensated according to actuator operation in a high temperature (85°C) environment.

[0153] In addition, FIGS. 7, 10, and 13 are graphs for aberrations of an optical system (1000) in low temperature (-40°C), room temperature (20°C), and high temperature (85°C) environments, respectively, and are graphs measuring spherical aberration (longitudinal spherical aberration), astigmatic field curves, and distortion from left to right. In FIGS. 7, 10, and 13, the X-axis may represent a focal length (mm) or a degree of distortion (%), and the Y-axis may represent the height of the image. In addition, the graph for spherical aberration is a graph for light in wavelength bands of about 920 nm, about 940 nm, and about 960 nm, and the graphs for astigmatic aberration and distortion aberration are graphs for light in wavelength bands of 940 nm.

[0154] In the aberration diagrams of FIGS. 7, 10, and 13, the closer each curve is to the Y-axis, the better the aberration correction function can be interpreted. Referring to FIGS. 7, 10, and 13, it can be seen that the optical system (1000) according to the first embodiment has measurement values ​​close to the Y-axis in almost all areas.

[0155] Referring to FIGS. 5 to 13, it can be seen that the optical system (1000) according to the first embodiment exhibits little or no change in MTF characteristics and aberration characteristics even when the temperature changes in the range of low temperature (-40°C) to high temperature (85°C). Specifically, it can be seen that the change in MTF characteristics at low temperature (-40°C) and high temperature (85°C) is less than 10% of that at room temperature (22°C).

[0156] That is, the optical system (1000) according to the first embodiment can maintain excellent optical characteristics in various temperature ranges. In detail, the optical system (1000) may include a first lens (100) made of the same plastic material as the second lens (200) and the third lens (300).

[0157] At this time, the first to third lenses (100, 200, 300) according to the first embodiment are provided with set refractive indices, shapes, thicknesses, etc., so that they can mutually compensate for changes in focal length caused by changes in refractive indices that vary with temperature. Accordingly, the optical system (1000) can prevent or minimize changes in optical characteristics in a temperature range from low temperature (-40°C) to high temperature (85°C), and can maintain improved optical characteristics.

[0158]

[0159] Below, with reference to Table 14, a plurality of lenses according to the second embodiment will be described in more detail.

[0160] Lens surface curvature radius (mm) thickness or gap (mm) refractive index Abbe number effective diameter size first lens first surface (S1) 1.685 1.072 1.585 0 26.0000 2.700 second surface (S2) 3.866 0.270 2.514 STOP-infinity 0.979 1.832 second lens third surface (S3) - 1.588 0.600 1.6800 18.1000 1.700 fourth surface (S4) - 2.137 0.485 1.977 third lens fifth surface (S5) 3.407 1.183 1.6800 18.1000 2.486 sixth surface (S6) 3.350 0.146 3.400 filter infinity 0.300 4.063 Infinity0.5004.184 cover glass, Infinity0.4004.394 image sensor, Infinity0.0504.528

[0161] Table 14 shows the radius of curvature of the first to third lenses (100, 200, 300) according to the second embodiment, the thickness of each lens on the optical axis (OA), the distance between each lens on the optical axis (OA), the refractive index for light in the d-line (587.562 mm) wavelength band, the Abbe's Number, and the size of the clear aperture (CA). Here, the lens data described in Table 14 is data at room temperature (about 20°C). Referring to FIG. 14 and Table 14, the first lens (100) of the optical system (1500) according to the second embodiment may be made of a plastic material and may have positive (+) refractive power on the optical axis (OA).

[0162] The first surface (S1) on the object side of the first lens (100) in the optical axis (OA) may have a convex shape, and the second surface (S2) on the sensor side may have a concave shape. The first lens (100) may have a meniscus shape in which the object side is convex in the optical axis (OA). The first lens (100) may have a meniscus shape in which the sensor side is concave in the optical axis (OA). At least one of the first surface (S1) and the second surface (S2) may be an aspherical surface (Asphere). For example, both the first surface (S1) and the second surface (S2) may be aspherical surfaces (Asphere).

[0163] The second lens (200) may have positive (+) or negative (-) refractive power on the optical axis (OA). The second lens (200) may have negative (-) refractive power on the optical axis (OA). The second lens (200) may be made of a plastic material.

[0164] The third surface (S3) on the object side of the second lens (200) on the optical axis (OA) may have a concave shape, and the fourth surface (S4) on the sensor side may have a convex shape. The second lens (200) may have a concave meniscus shape on the object side on the optical axis (OA). The second lens (200) may have a convex meniscus shape on the sensor side on the optical axis (OA). At least one of the third surface (S3) and the fourth surface (S4) may be an aspherical surface (Asphere). For example, both the third surface (S3) and the fourth surface (S4) may be aspherical surfaces (Asphere).

[0165] The third lens (300) may have positive (+) or negative (-) refractive power on the optical axis (OA). The third lens (300) may have positive (+) refractive power on the optical axis (OA). The third lens (300) may be made of a plastic material.

[0166] The object-side fifth surface (S5) of the third lens (300) on the optical axis (OA) may have a convex shape, and the sixth surface (S6) may be concave. The third lens (300) may have a meniscus shape that is convex from the optical axis (OA) toward the object side. Alternatively, the fifth surface (S5) may have a convex shape from the optical axis (OA), and the sixth surface (S6) may be convex from the optical axis (OA). That is, the third lens (300) may have a biconvex shape from the optical axis (OA). Alternatively, the fifth surface (S5) may have a concave shape from the optical axis (OA), and the sixth surface (S6) may be convex from the optical axis (OA). That is, the third lens (300) may have a meniscus shape that is convex from the optical axis (OA) toward the sensor side. In contrast, the fifth surface (S5) may have a concave shape in the optical axis (OA), and the sixth surface (S6) may be concave in the optical axis (OA). That is, the third lens (300) may have a concave shape on both sides in the optical axis (OA).

[0167] At least one of the fifth surface (S5) and the sixth surface (S6) may be an aspherical surface (Asphere). For example, both the fifth surface (S5) and the sixth surface (S6) may be aspherical surfaces (Asphere). The fifth surface (S5) may include at least one inflection point. The fifth surface (S5) may include at least one inflection point in a flange region outside the effective diameter region. The sixth surface (S6) may include at least one inflection point. The sixth surface (S6) may include at least one inflection point within the effective diameter region.

[0168]

[0169] Table 15 below shows Sag data according to the vertical height (0.2 mm interval) of the optical axis (OA) of each of the object side (first surface (S1)) and sensor side (second surface (S2)) of the first lens (100) at room temperature (approximately 20°C).

[0170] In addition, Table 16 is data on lens thickness according to the vertical height (0.2 mm interval) of the optical axis (OA) at room temperature (approximately 20°C). In detail, D_1 in Table 16 is the center thickness of the first lens (100), which is the thickness (mm) at the optical axis (OA) of the first lens (100). In addition, D_1_ET in Table 16 means the thickness (mm) in the optical axis (OA) direction at the end of the effective area of ​​the first lens (100). In detail, it means the distance (mm) in the optical axis (OA) direction between the end of the effective area of ​​the object-side surface (first surface (S1)) of the first lens (100) and the end of the effective area of ​​the sensor-side surface (second surface (S2)) of the first lens (100).

[0171]

[0172] Vertical height of the optical axis from the optical axis on the object side of the first lens (mm) Sag of the object side of the first lens (mm) Vertical height of the optical axis from the optical axis on the sensor side of the first lens (mm) Sag of the sensor side of the first lens (mm) 0000.0052330.20.0119230.20.0216930.40.0483440.40.0521920.60.1114350.60.1043320.80.2057680.80.0052331.00.341051.00.0216931.20.54262--

[0173] Vertical height of the optical axis from the optical axis (mm) Thickness of the first lens in the optical axis direction (mm) 01.07 201 (D_1) 0.2 1.06 5 32 0.4 1.04 5 36 0.6 1.01 2 7 7 0.8 0.9 7 0 5 8 1.00 9 4 16 5 1.20 75 213 (D_1_ET)

[0174] Vertical height of the optical axis from the optical axis (mm) Slope angle (degree) of the object side (first surface (S1)) of the first lens Slope angle (degree) of the sensor side (second surface (S2)) of the first lens 00.00.00.26.03.00.413.06.00.621.011.00.829.018.01.038.00.01.251.0-

[0175] Referring to Tables 15 and 16, the thickness of the first lens (100) in the direction of the optical axis (OA) may become thinner as it goes from the optical axis (OA) toward the end of the effective diameter of the first lens (100). In addition, Table 17 shows data on the Slope Angle (degree) of the object-side surface (first surface (S1)) of the first lens and the sensor-side surface (second surface (S2)) of the first lens according to the vertical height (0.2 mm interval) of the optical axis (OA) at room temperature (approximately 20°C). The Slope Angle refers to the angle formed by the tangent line touching the lens surface and the line perpendicular to the optical axis (OA). Accordingly, the first lens (100) may have improved aberration control characteristics by controlling incident light.

[0176]

[0177] Table 18 below shows Sag data according to the vertical height (0.2 mm interval) of the optical axis (OA) of each of the object side (third side (S3)) and sensor side (fourth side (S4)) of the second lens (200) at room temperature (approximately 20°C).

[0178] In addition, Table 19 is data on lens thickness according to the vertical height (0.2 mm interval) of the optical axis (OA) at room temperature (approximately 20°C). In detail, D_2 in Table 19 is the center thickness of the second lens (200), which is the thickness (mm) at the optical axis (OA) of the second lens (200). In addition, D_2_ET in Table 19 means the thickness (mm) in the optical axis (OA) direction at the end of the effective area of ​​the second lens (200). In detail, it means the distance (mm) in the optical axis (OA) direction between the end of the effective area of ​​the object-side surface (third surface (S3)) of the second lens (200) and the end of the effective area of ​​the sensor-side surface (fourth surface (S4)) of the second lens (200).

[0179]

[0180] Vertical height of the optical axis from the optical axis on the object side of the second lens (mm)Sag of the object side of the second lens (mm)Vertical height of the optical axis from the optical axis on the sensor side of the second lens (mm)Sag of the sensor side of the second lens (mm)00000.2-0.0127270.2-0.0095090.4-0.0523790.4-0.0396620.6-0.1228520.6-0.0940850.8-0.227980.8-0.1752631.0-0.364911.0-0.279893--1.2-0.391382

[0181] Vertical height of the optical axis from the optical axis (mm) Thickness of the second lens in the optical axis direction (mm) 0 0.6 (D_2) 0.2 0.6 0 3 2 2 0.4 0.6 1 2 7 2 0.6 0.6 2 8 7 7 0.8 0.6 5 2 7 2 1.0 0.6 8 5 0 2 (D_2_ET)

[0182] Vertical height of the optical axis from the optical axis (mm) Slope angle (degree) of the object side (third surface (S3)) of the second lens Slope angle (degree) of the sensor side (fourth surface (S4)) of the second lens 00.00.00.2-7.0-5.00.4-15.0-11.00.6-23.0-18.00.8-31.0-25.01.0-36.0-29.01.2--27.0

[0183] Referring to Tables 18 and 19, the thickness of the second lens (200) in the direction of the optical axis (OA) may become thicker as it goes from the optical axis (OA) toward the end of the effective diameter of the second lens (200). In addition, Table 20 shows data on the Slope Angle (degree) of the object-side surface (third surface (S3)) of the second lens (200) and the sensor-side surface (fourth surface (S4)) of the second lens (200) according to the vertical height (0.2 mm interval) of the optical axis (OA) at room temperature (approximately 20°C). The Slope Angle refers to the angle formed by the tangent line touching the lens surface and the line perpendicular to the optical axis (OA). Accordingly, the second lens (200) can prevent or minimize changes in optical characteristics depending on temperature in a temperature range from low to high temperature.

[0184]

[0185] Table 21 below shows Sag data according to the vertical height (0.2 mm interval) of the optical axis (OA) of each of the object side (fifth side (S5)) and sensor side (sixth side (S6)) of the third lens (300) at room temperature (approximately 20°C).

[0186] In addition, Table 22 is data on lens thickness according to the vertical height of the optical axis (OA) at room temperature (approximately 20°C). In detail, D_3 in Table 22 is the center thickness of the third lens (300), which is the thickness (mm) at the optical axis (OA) of the third lens (300). In addition, D_3_ET in Table 22 means the thickness (mm) in the optical axis (OA) direction at the end of the effective area of ​​the third lens (300). In detail, it means the distance (mm) in the optical axis (OA) direction between the end of the effective area of ​​the object-side surface (the fifth surface (S5)) of the third lens (300) and the end of the effective area of ​​the sensor-side surface (the sixth surface (S6)) of the third lens (300).

[0187]

[0188] Vertical height of the optical axis from the optical axis on the object side of the third lens (mm) Sag of the object side of the third lens (mm) Vertical height of the optical axis from the optical axis on the sensor side of the third lens (mm) Sensor side of the third lens Sag(mm)00000.20.0057150.20.0058950.40.0211190.40.0226710.60.041840.60.0476390.80.0628780.80.0766611.00.080 521.00.1049941.20.093121.20.1281541.40.1001651.40.1419841.60.0998261.60.1417131.8-1.80.120272.0-2.00.065669

[0189] Vertical height of the optical axis from the optical axis (mm) Thickness of the third lens in the optical axis direction (mm) 01.18348 (D_3) 0.21.183660.41.185040.61.189280.81.197271.01.207961.21.218521.41.22531.61.22537 (D_3_ET)

[0190] Vertical height of the optical axis from the optical axis (mm) Slope angle (degree) of the object side (fifth surface (S5)) of the third lens Slope angle (degree) of the sensor side (sixth surface (S6)) of the third lens 0000.23.03.00.45.06.00.66.07.00.85.08.01.04.07.01.22.05.01.41.02.01.6-1.0-2.01.8--10.02.0-20.0

[0191] Referring to Tables 21 and 22, the thickness of the third lens (300) in the direction of the optical axis (OA) may become thicker as it goes from the optical axis (OA) toward the end of the effective diameter of the third lens (300). In addition, Table 23 shows data on the Slope Angle (degree) of the object-side surface (fifth surface (S5)) of the third lens (300) and the sensor-side surface (sixth surface (S6)) of the third lens (300) according to the vertical height (0.2 mm interval) of the optical axis (OA) at room temperature (approximately 20°C). The Slope Angle refers to the angle formed by the tangent line touching the lens surface and the line perpendicular to the optical axis (OA). Accordingly, the third lens (300) can prevent or minimize changes in optical characteristics depending on temperature in a temperature range from low to high temperature.

[0192]

[0193] The values ​​of the aspherical coefficients of each lens surface in the optical system (1500) according to the second embodiment are as shown in Table 24 below.

[0194]

[0195] 1st side (S1) 2nd side (S2) 3rd side (S3) 4th side (S4) 5th side (S5) 6th side (S6) Y1.68493.8655-1.5879-2.13683.40683.3499K0.424712.69150.98540.5285-9.67740.9682A-0.00460.0063-0.0224-0.0761-0.0716-0.0536B-0.00280.00560.08510.05670.0342-0.0031C0.0015-0.0110 -0.17430.0281-0.01040.0092D-0.00090.01940.4186-0.10650.0023-0.0052E-0.0103-0.39330.1500-0.00040.0016F0.0000 0.1524-0.10850.0000-0.0003G0.00004.02E-021.41E-052.99E-05H0.0000-6.03E-03-2.47E-06-1.58E-06J1.28E-073.29E-08

[0196] In addition, the distance (first distance) between the first lens (100) and the second lens (200) in the optical system (1500) according to the second embodiment may be as shown in Table 25 below at room temperature (approximately 20°C).

[0197] The vertical height of the optical axis from the optical axis on the sensor side of the first lens (mm) The distance in the optical axis direction from the sensor side of the first lens to the object side of the aperture (mm) The distance in the optical axis direction from the sensor side of the aperture to the object side of the second lens (mm) The vertical height of the optical axis from the optical axis on the object side of the second lens (mm) 0 0.69 1 99 1 145 1 90 0.20 68 0 95 1 137 3 7 0.20 40 64 67 1 116 10.40 60 58 60 61 09 00 8 0.60 8 (L1) 0.49 7 1 07 1 36 0.8 (L1)

[0198] Referring to Table 25, the first gap (d12) may refer to the distance in the optical axis direction from the sensor side of the first lens (100) to the object side of the second lens (200). The first gap (d12) may be the sum of the distance in the optical axis direction from the sensor side of the first lens (100) to the object side of the aperture and the distance in the optical axis direction from the sensor side of the aperture to the object side of the second lens (200). The first gap (d12) may be a first air gap (d12). The first gap may become smaller as it goes from the optical axis (OA) to the first point (L1), which is the end of the effective diameter of the second surface (S2). Here, the value indicated by the first point (L1) is an approximate value of the effective radius of the second surface (S2) having a smaller effective diameter among the sensor side (second surface (S2)) of the first lens (100) and the object side (third surface (S3)) of the second lens (200) facing each other, and means an approximate value of 1 / 2 of the effective diameter value of the second surface (S2) described in Table 15.

[0199] The first interval may have a maximum value at the optical axis (OA) and a minimum value at the first point (L1). The maximum value of the first interval may be about 1 to about 1.4 times the minimum value. For example, in the second embodiment, the maximum value of the first interval may be about 1.03 times the minimum value.

[0200]

[0201] In addition, the distance (second distance) between the second lens (200) and the third lens (300) in the optical system (1500) according to the second embodiment may be as shown in Table 26 below at room temperature (approximately 20°C).

[0202]

[0203] Vertical height of the optical axis from the optical axis on the sensor side of the second lens (mm) Optical axis direction spacing of the second air gap (d23) (mm) (Second spacing) Vertical height of the optical axis from the optical axis on the object side of the third lens (mm) 0 0.48 49 10 0.20 5 0 0 1 3 0.20 40 5 45 6 9 0.40 6 0.62 0 8 3 0.60 8 0.72 30 5 0.81 0 0.84 5 3 2 1.0 1.2 (L2) 0.96 9 4 1 1.2 (L2)

[0204] Referring to Table 26, the second gap (d23) may refer to the direction of the optical axis from the sensor side of the second lens to the object side of the third lens. The second gap (d23) may be a second air gap (d23). The second gap may increase from the optical axis (OA) to the second point (L2), which is the end of the effective diameter of the fourth surface (S4). Here, the value referred to by the second point (L2) is an approximate value of the effective radius value of the fourth surface (S4) having a smaller effective diameter among the sensor side (fourth surface (S4)) of the second lens (200) and the object side (fifth surface (S5)) of the third lens (300) that face each other, and means an approximate value of half of the effective diameter value of the fourth surface (S4) described in Table 26.

[0205] The second interval may have a maximum value at the second point (L2) and a minimum value at the optical axis (OA). The maximum value of the second interval may be about 1.5 to about 2.5 times the minimum value. For example, in the second embodiment, the maximum value of the second interval may be about 2.0 times the minimum value.

[0206]

[0207] Figures 15 to 23 are graphs of the diffraction MTF characteristics and aberration of the optical system (1500) according to temperature.

[0208] In detail, FIG. 15 is a graph of the diffraction MTF characteristics of an optical system (1500) in a low temperature (-40°C) environment, and FIG. 16 is a graph of the diffraction MTF characteristics of an optical system (1500) in which the peak reference is compensated according to actuator operation in a low temperature (-40°C) environment. FIG. 18 is a graph of the diffraction MTF characteristics of an optical system (1500) in a room temperature (20°C) environment, and FIG. 19 is a graph of the diffraction MTF characteristics of an optical system (1500) in which the peak reference is compensated according to actuator operation in a room temperature (20°C) environment. Fig. 21 is a graph of the diffraction MTF characteristics of an optical system (1500) in a high temperature (85°C) environment, and Fig. 22 is a graph of the diffraction MTF characteristics of an optical system (1500) in which the peak reference is compensated according to actuator operation in a high temperature (85°C) environment.

[0209] In addition, FIGS. 17, 20, and 23 are graphs for aberrations of an optical system (1500) in low temperature (-40°C), room temperature (20°C), and high temperature (85°C) environments, respectively, and are graphs measuring spherical aberration (longitudinal spherical aberration), astigmatic field curves, and distortion from left to right. In FIGS. 17, 20, and 23, the X-axis may represent a focal length (mm) or a degree of distortion (%), and the Y-axis may represent the height of the image. In addition, the graph for spherical aberration is a graph for light in wavelength bands of about 920 nm, about 940 nm, and about 960 nm, and the graphs for astigmatic aberration and distortion aberration are graphs for light in wavelength bands of 940 nm.

[0210] In the aberration diagrams of FIGS. 17, 20, and 23, the closer each curve is to the Y-axis, the better the aberration correction function can be interpreted. Referring to FIGS. 17, 20, and 23, it can be seen that the optical system (1500) according to the second embodiment has measurement values ​​close to the Y-axis in almost all areas.

[0211] Referring to FIGS. 15 to 23, it can be seen that the optical system (1500) according to the second embodiment exhibits little or no change in MTF characteristics and aberration characteristics even when the temperature changes in the range of low temperature (-40°C) to high temperature (85°C). Specifically, it can be seen that the change in MTF characteristics at low temperature (-40°C) and high temperature (85°C) is less than 10% of that at room temperature (22°C).

[0212] That is, the optical system (1500) according to the second embodiment can maintain excellent optical characteristics in a variety of temperature ranges. In detail, the optical system (1500) may include a first lens (100) made of the same plastic material as the second lens (200) and the third lens (300).

[0213] At this time, the first to third lenses (100, 200, 300) according to the second embodiment are provided with set refractive indices, shapes, thicknesses, etc., so that they can mutually compensate for changes in focal length caused by changes in refractive indices that vary with temperature. Accordingly, the optical system (1500) can prevent or minimize changes in optical characteristics in a temperature range of low temperature (-40°C) to high temperature (85°C), and can maintain improved optical characteristics.

[0214]

[0215] The optical systems (1000, 1500) according to the first and second embodiments can satisfy at least one of the mathematical equations described below. Accordingly, the optical systems (1000, 1500) according to the present embodiment can prevent or minimize changes in optical characteristics depending on temperature in a temperature range from low to high temperature, thereby realizing improved optical characteristics at various temperatures. In addition, the optical systems (1000, 1500) according to the embodiments can have improved distortion and aberration characteristics at various temperatures by satisfying at least one of the mathematical equations described below. Terms expressed in some of the mathematical equations will be described with reference to FIG. 31.

[0216]

[0217] [Mathematical Formula 1]

[0218] 1.2 < L1_CT / L1_ET < 2

[0219] In mathematical expression 1, L1_CT is the thickness (mm) at the center of the first lens (100) at room temperature (about 20°C) along the optical axis (OA) of the first lens (100), and L1_ET means the thickness (mm) in the direction of the optical axis (OA) at the end of the effective area of ​​the first lens (100) at room temperature (about 20°C). When the optical system (1000) according to the first and second embodiments satisfies mathematical expression 1, a factor affecting the angle of view of the optical system (1000) can be set, and a factor affecting the effective focal length (EFL) can be set. In the first and second embodiments, mathematical expression 1 can preferably satisfy 1.3 < L1_CT / L1_ET < 1.8.

[0220]

[0221] [Equation 2]

[0222] 0.5 < L2_CT / L2_ET < 1.5

[0223] In mathematical expression 2, L2_CT is the thickness (mm) at the center of the second lens (200) at room temperature (about 20°C) and the thickness at the optical axis (OA) of the second lens (200). In addition, L2_ET refers to the thickness (mm) in the direction of the optical axis (OA) at the end of the effective area of ​​the second lens (100) at room temperature (about 20°C). L1_ET may be the thickness of the flange portion outside the effective diameter of the first lens (100). When the optical system (1000) according to the first and second embodiments satisfies mathematical expression 2, the optical system (1000) may have improved chromatic aberration reduction characteristics. In the first and second embodiments, mathematical expression 2 may preferably satisfy 0.8 < L2_CT / L2_ET < 1.3.

[0224]

[0225] [Equation 3]

[0226] 0.5 < L3_CT / L3_ET < 1.5

[0227] In mathematical expression 3, L3_CT is the thickness (mm) at the center of the third lens (300) at room temperature (about 20°C) and the thickness of the third lens (300) at the optical axis (OA). In addition, L3_ET refers to the thickness (mm) in the direction of the optical axis (OA) at the end of the effective area of ​​the third lens (300) at room temperature (about 20°C). L3_ET may be the thickness of the flange portion outside the effective diameter of the third lens (300). When the optical system (1000) according to the first and second embodiments satisfies mathematical expression 3, the optical system (1000) may have improved aberration reduction characteristics. In the first and second embodiments, mathematical expression 3 may preferably satisfy 0.8 < L3_CT / L3_ET < 1.2.

[0228]

[0229] [Equation 4]

[0230] 1.5 < n1 < 1.6

[0231] In mathematical expression 4, n1 is the refractive index of the first lens (100) for light in the d-line (587.6 nm) wavelength band. When mathematical expression 4 is satisfied, the refractive performance of the first lens (100) arranged closest to the object side in the optical system (1000) can be secured. In the first and second embodiments, mathematical expression 4 can preferably satisfy 1.55 < n1 < 1.6.

[0232]

[0233] [Equation 5]

[0234] 20 < v1 < 30

[0235] In mathematical expression 5, it refers to the Abbe number of the first lens (100). When mathematical expression 5 is satisfied, the refractive performance of the first lens (100) placed closest to the object side in the optical system (1000, 1500) can be secured. In the first and second embodiments, mathematical expression 5 can preferably satisfy 25 < v1 < 27.

[0236]

[0237] [Equation 6]

[0238] 1.5 < n2 < 1.7

[0239] In mathematical expression 6, n2 is the refractive index of the second lens (200) for light in the d-line (587.6 nm) wavelength band. When mathematical expression 6 is satisfied, the refractive performance of the second lens (200) arranged closest to the object side in the optical system (1000, 1500) can be secured. In the first and second embodiments, mathematical expression 6 can preferably satisfy 1.55 < n2 < 1.7.

[0240]

[0241] [Equation 7]

[0242] 1.2 < L3S2_max_sag to Sensor < 1.5

[0243] In mathematical expression 7, L3S2_max_sag to Sensor means the distance (mm) in the direction of the optical axis (OA) from the point of the maximum Sag value of the sensor side (sixth surface (S6)) of the third lens (300) to the image sensor (600). When mathematical expression 7 is satisfied, the size of the camera module including the optical system (1000, 1500) can be minimized. In the first and second embodiments, mathematical expression 7 can preferably satisfy 1.25 < L3S2_max_sag to Sensor < 1.4.

[0244]

[0245] [Equation 8]

[0246] 1 < BFL / L3S2_max_sag to Sensor < 1.5

[0247] In mathematical expression 8, L3S2_max_sag to Sensor means the distance (mm) in the direction of the optical axis (OA) from the point of the maximum sag value of the sensor-side surface (sixth surface (S6)) of the third lens (300) to the image sensor (600). BFL (Back focal length) is the distance (mm) in the optical axis (OA) from the vertex of the sensor-side surface of the lens closest to the image sensor (600) to the upper surface of the image sensor (600) at room temperature (approximately 20°C). When mathematical expression 8 is satisfied, the size of the camera module including the optical system (1000, 1500) can be minimized. In the first and second embodiments, mathematical expression 8 can preferably satisfy 1 < BFL / L3S2_max_sag to Sensor < 1.2.

[0248]

[0249] [Equation 9]

[0250] 10 < |L3S2_max slope| < 50

[0251] In mathematical expression 9, L3S2_max slope angle means the maximum value of the angle formed by the tangent line on the sensor side of the third lens (300) and the line perpendicular to the optical axis (OA). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 9, the optical system (1000, 1500) can minimize the flare phenomenon. In the first and second embodiments, mathematical expression 9 can preferably satisfy 12 < |L3S2_max slope| < 48.

[0252]

[0253] [Equation 10]

[0254] 1 < d23_max / d23_CT < 2

[0255] In mathematical expression 10, d23_max means the largest distance (mm) among the distances from the sensor side (fourth surface (S4)) of the second lens (200) to the object side (fifth surface (S5)) of the third lens (300) at room temperature (about 20°C), and d23_CT means the distance (mm) from the sensor side (fourth surface (S4)) of the second lens (200) to the object side (fifth surface (S5)) of the third lens (300) on the optical axis (OA) at room temperature (about 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 10, the optical system (1000, 1500) may have improved characteristics of peripheral angle of view, chromatic aberration, and distortion aberration. In the first and second embodiments, mathematical expression 10 can preferably satisfy 1.4 < d23_max / d23_CT < 2.

[0256]

[0257] [Equation 11]

[0258] 0.1 < L2_CT / L1_CT < 1

[0259] In mathematical expression 11, L2_CT refers to the central thickness of the second lens (200) in the direction of the optical axis (OA) at room temperature (approximately 20°C). In addition, L1_CT refers to the central thickness of the first lens (100) in the direction of the optical axis (OA) at room temperature (approximately 20°C). When mathematical expression 11 is satisfied, a factor affecting the angle of view of the optical system can be set, and a factor affecting the effective focal length (EFL) can be set. In the first and second embodiments, mathematical expression 11 can preferably satisfy 0.5 < L2_CT / L1_CT < 1.

[0260]

[0261] [Equation 12]

[0262] 0.5 < L2R1 / L2R2 < 2

[0263] In mathematical expression 12, L2R1 is the radius of curvature of the object-side surface (third surface (S3)) of the second lens (200) at room temperature (about 20°C), and L2R2 is the radius of curvature of the sensor-side surface (fourth surface (S4)) of the second lens (200) at room temperature (about 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 12, the optical system (1000, 1500) can have improved aberration control characteristics. In the first and second embodiments, mathematical expression 12 can preferably satisfy 0.7 < L2R1 / L2R2 < 1.8.

[0264]

[0265] [Equation 13]

[0266] 1 < CA_L1 / CA_L2 < 1.5

[0267] In mathematical expression 13, CA_L1 denotes the size of the effective diameter of the first lens (100), and CA_L2 denotes the size of the effective diameter of the second lens (200). The size of the effective diameter of each lens denotes the average value of the object side and the sensor side of the lens. When mathematical expression 13 is satisfied, the deterioration of optical characteristics due to temperature change can be suppressed, and the optical system (1000, 1500) can control the incident light and set the factors affecting the aberration. In the first and second embodiments, mathematical expression 13 can preferably satisfy 1 < CA_L1 / CA_L2 < 1.42.

[0268]

[0269] [Equation 14]

[0270] 0.5 < CA_L2 / CA_L3 < 1

[0271] In mathematical expression 14, CA_L2 denotes the size of the effective diameter of the second lens (200), and CA_L3 denotes the size of the effective diameter of the third lens (300). The size of the effective diameter of each lens denotes the average value of the object side and the sensor side of the lens. When mathematical expression 14 is satisfied, the deterioration of optical characteristics due to temperature change can be suppressed, and the optical system (1000, 1500) can control the incident light and set the factors affecting the aberration. In the first and second embodiments, mathematical expression 14 can preferably satisfy 0.6 < CA_L2 / CA_L3 < 8.

[0272]

[0273] [Equation 15]

[0274] 0.5 < L_CT_Max / Air_Max < 2

[0275] In mathematical expression 15, L_CT_Max means the value having the largest center thickness among the first to third lenses (100, 200, 300) in the optical axis (OA) direction. In addition, Air_Max means the larger value among the distance between the first lens (100) and the second lens (200) and the distance between the second lens (200) and the third lens (300) in the optical axis (OA) direction. When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 15, the optical system (1000, 1500) can have good optical performance and TTL reduction characteristics at the set angle of view and focal length. In the first and second embodiments, mathematical expression 15 can preferably satisfy 0.8 < L_CT_Max / Air_Max < 1.8.

[0276]

[0277] [Equation 16]

[0278] 1.5 < ∑L_CT / ∑Air_CT < 3.5

[0279] In mathematical expression 16, ∑L_CT means the sum of the center thicknesses of the first to third lenses (100, 200, 300) in the optical axis (OA) direction. In addition, ∑Air_CT means the sum of the distance between the first lens (100) and the second lens (200) and the distance between the second lens (200) and the third lens (300) in the optical axis (OA) direction. When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 16, the optical system (1000, 1500) can have good optical performance and TTL reduction characteristics at the set angle of view and focal length. In the first and second embodiments, mathematical expression 16 can preferably satisfy 1.5 < ∑L_CT / ∑Air_CT < 3.2.

[0280]

[0281] [Equation 17]

[0282] 10 < ∑Abb / ∑Index < 20

[0283] In mathematical expression 17, ΣIndex means the sum of the refractive indices at the d-lines of the first to third lenses (100, 200, 300) at room temperature (approximately 20°C). In addition, ΣAbb means the sum of the Abbe's numbers of the first to third lenses (100, 200, 300) at room temperature (approximately 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 17, the optical system (1000, 1500) can have improved aberration characteristics and resolution. In the first and second embodiments, mathematical expression 17 can preferably satisfy 12 < ∑Abb / ∑Index < 17.

[0284]

[0285] [Equation 18]

[0286] 1.5 < CA_L1S1 / CA_min < 2

[0287] In mathematical expression 18, CA_L1S1 is the size of the effective diameter of the object-side surface (S1) of the first lens (100), and CA_min is the size of the effective diameter (CA) of the lens surface having the smallest effective diameter size (CA) at room temperature (about 20°C) among the lens surfaces of the plurality of lenses (100, 200, 300) included in the optical system (1000, 1500). When the optical systems (1000, 1500) according to the first and second embodiments satisfy mathematical expression 18, the optical systems (1000, 1500) may have optical performance and TTL reduction structural characteristics. In the first and second embodiments, mathematical expression 18 may preferably satisfy 1.5 < CA_L1S1 / CA_min < 1.6.

[0288]

[0289] [Equation 19]

[0290] 1.5 < CA_max / CA_min < 2.5

[0291] In mathematical expression 19, CA_max is the size of the effective diameter (CA) of the lens surface having the largest effective diameter size (CA) at room temperature (about 20°C) among the lens surfaces of the plurality of lenses (100, 200, 300) included in the optical system (1000, 1500). In addition, CA_min is the size of the effective diameter (CA) of the lens surface having the smallest effective diameter size (CA) at room temperature (about 20°C) among the lens surfaces of the plurality of lenses (100, 200, 300) included in the optical system (1000, 1500). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 19, the optical system (1000, 1500) may have optical performance and TTL reduction structural characteristics. In the first and second embodiments, mathematical expression 19 can preferably satisfy 1.8 < CA_max / CA_min < 2.4.

[0292]

[0293] [Equation 20]

[0294] 1 < CA_max / CA_Aver < 2

[0295] In mathematical expression 20, CA_max is the size of the effective diameter (CA) of the lens surface having the largest effective diameter size (CA) at room temperature (approximately 20°C) among the lens surfaces of the plurality of lenses (100, 200, 300) included in the optical system (1000, 1500). In addition, CA_Aver means the average (mm) of the sizes of the effective diameters (CA) of the lens surfaces (object side, sensor side) of the plurality of lenses (100, 200, 300) included in the optical system (1000, 1500) at room temperature (approximately 20°C). When the optical systems (1000, 1500) according to the first and second embodiments satisfy mathematical expression 20, the optical systems (1000, 1500) may have optical performance and TTL reduction structural characteristics. In the first and second embodiments, mathematical expression 20 preferably satisfies 1.4 < CA_max / CA_Aver < 1.6.

[0296]

[0297] [Equation 21]

[0298] 0.5 < CA_min / CA_Aver < 1

[0299] In mathematical expression 21, CA_min is the effective diameter size (CA) of the lens surface having the smallest effective diameter size (CA) at room temperature (about 20°C) among the lens surfaces of the plurality of lenses (100, 200, 300) included in the optical system (1000, 1500). In addition, CA_Aver means the average (mm) of the effective diameter (CA) sizes of the lens surfaces (object side, sensor side) of the plurality of lenses (100, 200, 300) included in the optical system (1000, 1500) at room temperature (about 20°C). When the optical systems (1000, 1500) according to the first and second embodiments satisfy mathematical expression 21, the optical systems (1000, 1500) can be provided with a slim and compact structure, and can have an appropriate size for implementing optical performance in a low-temperature to high-temperature range. In the first and second embodiments, mathematical expression 21 can preferably satisfy 0.6 < CA_min / CA_Aver < 0.8.

[0300]

[0301] [Equation 22]

[0302] 0.5 < CA_max / (2*ImgH) < 1

[0303] In mathematical expression 22, CA_max is the size of the effective diameter (CA) of the lens surface having the largest effective diameter size (CA) at room temperature (approximately 20°C) among the lens surfaces of the plurality of lenses (100, 200, 300) included in the optical system (1000, 1500). In addition, ImgH is the value of the vertical distance of the optical axis (OA) from the 0 field area of ​​the image surface center of the image sensor (600) overlapping with the optical axis (OA) at room temperature (approximately 20°C) to the 1.0 field area of ​​the image sensor (600). That is, ImgH means 1 / 2 of the total diagonal length (mm) of the image sensor (600) at room temperature (approximately 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 22, the optical system (1000, 1500) can be provided with a slim and compact structure and can have an appropriate size for implementing optical performance in a temperature range from low to high temperature. In the first and second embodiments, mathematical expression 22 can preferably satisfy 0.7 < CA_max / (2*ImgH) < 0.9.

[0304]

[0305] [Equation 23]

[0306] 1.5 < f / L1R1 < 3

[0307] In mathematical expression 23, f denotes the effective focal length (mm) of the optical system (1000, 1500) at room temperature (about 20°C). f may be an Effective Focal Length (EFL). In addition, L1R1 denotes the radius of curvature of the object-side surface (the first surface (S1)) of the first lens (100) at room temperature (about 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 23, the optical system (1000, 1500) may be provided with a TTL reduction structure. In the first and second embodiments, mathematical expression 23 may preferably satisfy 1.8 < f / L1R1 < 3.

[0308]

[0309] [Equation 24]

[0310] 0.5 < EPD / L1R1 < 1.5

[0311] In mathematical expression 24, EPD (Entrance Pupil Diameter) means the diameter of the entrance pupil. In addition, L1R1 is the radius of curvature of the object-side surface (first surface (S1)) of the first lens (100) at room temperature (approximately 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 24, the optical system (1000, 1500) can have incident light control characteristics. In the first and second embodiments, mathematical expression 24 can preferably satisfy 0.8 < EPD / L1R1 < 1.4.

[0312]

[0313] [Equation 25]

[0314] 0.1 < |f1 / f2| < 1.5

[0315] In mathematical expression 25, f1 is the focal length (mm) of the first lens (100) at room temperature (about 20°C), and f2 is the focal length (mm) of the second lens (200) at room temperature (about 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 25, the optical system (1000, 1500) can have appropriate refractive power for controlling the incident light path of the first lens (100) and the second lens (200), and the optical system (1000, 1500) can have improved resolution. In the first and second embodiments, mathematical expression 25 can preferably satisfy 0.2 < |f1 / f2| < 1.2.

[0316]

[0317] [Equation 26]

[0318] 5 < TTL < 6

[0319] In mathematical expression 26, TTL is the distance (mm) from the object-side surface (first surface (S1)) of the first lens (100) to the upper surface of the image sensor (600) on the optical axis (OA) in an environment of room temperature (approximately 20°C). When mathematical expression 26 is satisfied, a suitable vehicle optical system can be provided. In the first and second embodiments, mathematical expression 26 can preferably satisfy 5.3 < TTL < 6.

[0320]

[0321] [Equation 27]

[0322] 2 < ImgH < 3

[0323] In mathematical expression 27, ImgH is a value of the vertical distance of the optical axis (OA) from the 0 field area of ​​the image sensor (600) at the center of the top surface overlapping with the optical axis (OA) to the 1.0 field area of ​​the image sensor (600) at room temperature (approximately 20°C). That is, ImgH means 1 / 2 of the total diagonal length (mm) of the image sensor (600) at room temperature (approximately 20°C). When mathematical expression 27 is satisfied, an optical system having a sensor size for a vehicle can be provided. In the first and second embodiments, mathematical expression 27 can preferably satisfy 2.2 < ImgH < 2.3.

[0324]

[0325] [Equation 28]

[0326] 1.2 < BFL < 1.8

[0327] In mathematical expression 28, the BFL (Back focal length) is the distance (mm) on the optical axis (OA) from the vertex of the sensor-side surface of the lens closest to the image sensor (600) to the upper surface of the image sensor (600) at room temperature (approximately 20°C). When mathematical expression 28 is satisfied, the installation space for the filter (400) and the cover glass can be secured, and the assemblability of the components can be improved and the joint reliability can be improved through the gap between the image sensor (400) and the last lens. When the BFL is less than the range of mathematical expression 28, some of the light traveling to the image sensor may not be transmitted to the image sensor, which may cause a decrease in resolution. When the BFL exceeds the range of mathematical expression 28, stray light may be introduced, which may deteriorate the aberration characteristics of the optical system. In the first and second embodiments, mathematical expression 28 may preferably satisfy 1.3 < BFL < 1.6.

[0328]

[0329] [Equation 29]

[0330] 3 < f < 5

[0331] In mathematical expression 29, f represents the effective focal length (mm) of the optical system (1000, 1500) at room temperature (approximately 20°C). F may be an Effective Focal Length (EFL). When mathematical expression 29 is satisfied, a focal length suitable for a vehicle optical system can be set. In the first and second embodiments, mathematical expression 29 preferably satisfies 4 < f < 5.

[0332]

[0333] [Equation 30]

[0334] 40 < FOV < 60

[0335] In mathematical expression 30, FOV refers to the field of view (FOV) of the optical system (1000, 1500) in an environment of room temperature (approximately 20°C), low temperature (approximately -40°C), and high temperature (approximately 85°C). When mathematical expression 30 is satisfied, an angle of view suitable for a vehicle optical system can be provided. In the first and second embodiments, mathematical expression 30 can preferably satisfy 45 < FOV < 59.

[0336]

[0337] [Equation 31]

[0338] 1.2 < TTL / CA_max < 1.8

[0339] In mathematical expression 31, TTL is the distance (mm) from the object-side surface (first surface (S1)) of the first lens (100) to the image surface of the image sensor (600) on the optical axis (OA) at room temperature (approximately 20°C). In addition, CA_max is the size of the effective diameter (CA) of the lens surface having the largest effective diameter size (CA) at room temperature (approximately 20°C) among the lens surfaces of the plurality of lenses (100, 200, 300) included in the optical system (1000, 1500). When the optical systems (1000, 1500) according to the first and second embodiments satisfy mathematical expression 31, the optical systems (1000, 1500) have good optical performance at the center and periphery of the field of view (FOV), and can be provided in a slim and compact structure. In the first and second embodiments, mathematical expression 31 can preferably satisfy 1.4 < TTL / CA_max < 1.8.

[0340]

[0341] [Equation 32]

[0342] 2 < TTL / ImgH < 2.8

[0343] In mathematical expression 32, TTL is the distance (mm) from the object-side surface (first surface (S1)) of the first lens (100) to the upper surface of the image sensor (600) along the optical axis (OA) at room temperature (approximately 20°C). In addition, ImgH is the value of the vertical distance of the optical axis (OA) from the 0 field area of ​​the center of the upper surface of the image sensor (600) overlapping with the optical axis (OA) to the 1.0 field area of ​​the image sensor (600) at room temperature (approximately 20°C). In other words, ImgH means half of the total diagonal length (mm) of the image sensor (600) at room temperature (approximately 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 32, the optical system (1000, 1500) can secure a BFL (Back focal length) for applying a relatively large image sensor (600), for example, a large image sensor (600) of about 1 inch, and can have a smaller TTL, thereby implementing high image quality and having a slim structure. In the first and second embodiments, mathematical expression 32 can preferably satisfy 2.3 < TTL / ImgH < 2.7.

[0344]

[0345] [Equation 33]

[0346] 0.2 < BFL / ImgH < 0.7

[0347] In mathematical expression 33, BFL (Back focal length) is the distance (mm) from the vertex of the sensor-side surface of the lens closest to the image sensor (600) to the upper surface of the image sensor (600) on the optical axis (OA) at room temperature (approximately 20°C). In addition, ImgH is the value of the vertical distance of the optical axis (OA) from the 0 field area of ​​the upper surface center of the image sensor (600) overlapping with the optical axis (OA) to the 1.0 field area of ​​the image sensor (600) at room temperature (approximately 20°C). In other words, ImgH means 1 / 2 of the total diagonal length (mm) of the image sensor (600) at room temperature (approximately 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 33, the optical system (1000, 1500) can secure a BFL (Back focal length) for applying a relatively large-sized image sensor (600), for example, a large image sensor (600) of about 1 inch, and can minimize the gap between the last lens and the image sensor (600), thereby having good optical characteristics in the center and periphery of the field of view (FOV). In the first and second embodiments, mathematical expression 33 can preferably satisfy 0.5 < BFL / ImgH < 0.7.

[0348]

[0349] [Equation 34]

[0350] 3 < TTL / BFL < 5

[0351] In mathematical expression 34, TTL is the distance (mm) from the object-side surface (first surface (S1)) of the first lens (100) to the upper surface of the image sensor (600) on the optical axis (OA) at room temperature (approximately 20°C). In addition, BFL (Back focal length) is the distance (mm) from the vertex of the sensor-side surface of the lens closest to the image sensor (600) to the upper surface of the image sensor (600) on the optical axis (OA) at room temperature (approximately 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 34, the optical system (1000, 1500) can be provided in a slim and compact manner while securing BFL. Preferably, in the first and second embodiments, mathematical expression 34 can satisfy 3.5 < TTL / BFL < 4.5.

[0352]

[0353] [Equation 35]

[0354] 0.5 < f / TTL < 1

[0355] In mathematical expression 35, f denotes the effective focal length (mm) of the optical system (1000, 1500) at room temperature (approximately 20°C). F may be EFL (Effective Focal Length). In addition, TTL denotes the distance (mm) from the object-side surface (first surface (S1)) of the first lens (100) to the image surface of the image sensor (600) on the optical axis (OA) in an environment of room temperature (approximately 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 35, the optical system (1000, 1500) can be provided in a slim and compact manner. Preferably, in the first and second embodiments, mathematical expression 35 can satisfy 0.7 < f / TTL < 0.9.

[0356]

[0357] [Equation 36]

[0358] 2.5 < f / BFL < 4

[0359] In mathematical expression 36, f denotes the effective focal length (mm) of the optical system (1000, 1500) at room temperature (approximately 20°C). f may be an Effective Focal Length (EFL). In addition, the Back Focal Length (BFL) is the distance (mm) from the vertex of the sensor-side surface of the lens closest to the image sensor (600) to the top surface of the image sensor (600) on the optical axis (OA) at room temperature (approximately 20°C). When the optical systems (1000, 1500) according to the first and second embodiments satisfy mathematical expression 36, the optical systems (1000, 1500) can have a set angle of view and an appropriate focal length, and can be provided in a slim and compact manner. In addition, the optical systems (1000, 1500) can minimize the gap between the last lens and the image sensor (600), and thus can have good optical characteristics at the periphery of the field of view (FOV). In the first and second embodiments, preferably, mathematical expression 36 can satisfy 2.6 < f / BFL < 3.6.

[0360]

[0361] [Equation 37]

[0362] 1.5 < f / ImgH < 2.5

[0363] In mathematical expression 37, f denotes the effective focal length (mm) of the optical system (1000, 1500) at room temperature (approximately 20°C). F may be the Effective Focal Length (EFL). In addition, ImgH denotes the vertical distance of the optical axis (OA) from the 0 field area of ​​the image sensor (600) at the center of the image plane overlapping with the optical axis (OA) to the 1.0 field area of ​​the image sensor (600) at room temperature (approximately 20°C). In other words, ImgH denotes half of the total diagonal length (mm) of the image sensor (600) at room temperature (approximately 20°C). When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 37, the optical system (1000, 1500) can have improved aberration characteristics by applying a relatively large-sized image sensor (600), for example, a large image sensor (600) of about 1 inch. In the first and second embodiments, mathematical expression 37 can preferably satisfy 1.7 < f / ImgH < 2.2.

[0364]

[0365] [Equation 38]

[0366] 2 < f / EPD < 2.3

[0367] In mathematical expression 38, f represents the effective focal length (mm) of the optical system (1000, 1500) at room temperature (approximately 20°C). F may be EFL (Effective Focal Length). In addition, EPD (Entrance Pupil Diameter) represents the diameter of the entrance pupil. In the first and second embodiments, mathematical expression 38 may preferably satisfy 2 < f / EPD < 2.2.

[0368]

[0369] [Equation 39]

[0370] 1.8 < Fno < 2.2

[0371] In mathematical expression 39, Fno represents the F-number of the optical system. When the optical system (1000, 1500) according to the first and second embodiments satisfies mathematical expression 39, it can take pictures in a dark environment as well as in a bright environment, and in particular, it can detect near infrared ray light. In the first and second embodiments, mathematical expression 38 can preferably satisfy 2 < Fno < 2.2.

[0372]

[0373] [Equation 40]

[0374]

[0375] In mathematical expression 40, Z can represent Sag, which is the distance from any position on the aspherical surface to the vertex of the aspherical surface along the optical axis. In addition, Y can represent the distance from any position on the aspherical surface to the optical axis in the direction perpendicular to the optical axis. In addition, c can represent the curvature of the lens, and K can represent the conic constant. In addition, A, B, C, D, … can represent aspheric coefficients.

[0376]

[0377] That is, in the optical system (1000, 1500) according to the first and second embodiments, the first lens (100), the second lens (200), and the third lens (300) may be provided with the same material, and may satisfy at least one of the mathematical expressions 1 to 40 described above. Accordingly, the optical system (1000, 1500) may prevent or minimize changes in optical characteristics depending on temperature, and may have improved optical characteristics at various temperatures.

[0378] In addition, the optical system (1000, 1500) according to the first and second embodiments can have improved optical characteristics by preventing or minimizing changes in distortion and aberration characteristics at various temperatures by satisfying at least one of mathematical expressions 1 to 40.

[0379]

[0380] The following Table 27 is about the items of the mathematical formulas described above in the optical system (1000, 1500) according to the first and second embodiments of the present invention, and is about the focal lengths of the first to third lenses (100, 200, 300) at room temperature (approximately 20°C), the TTL (Total track length), BFL (Back focal length), F value, ImgH, and effective focal length (EFL) values ​​of the optical system (1000, 1500) according to temperature.

[0381] Table 28 shows the result values ​​for the mathematical expressions 1 to 39 described above in the optical system (1000, 1500) according to the first and second embodiments of the present invention.

[0382]

[0383] First embodiment Second embodiment L1_CT1.2326mm1.0720mmL2_CT1.1452mm0.6000mmL3_CT0.7000mm1.1835mmL1_ET0.8302mm0.6050mmL2_ET0.9396mm0.6000mmL3_ET0.8404mm1.1400mmf1 (room temperature (about 20℃))3.4669mm4.4860mmf2 (room temperature (about 20℃))2.8930mm-16.7138mmf3 (room temperature (about 20℃))-2.3784mm43.0105mmEPD (room temperature (about 20℃))2.0012mm2.3009mmImgH (room temperature (about 20℃))2.2680mm2.2680mmTD(L1S1~L3S2) (Room temperature (approximately 20℃))3.8698mm4.5896mmSD(Stop~L3S2) (Room temperature (approximately 20℃))2.5872mm3.2477mmEFL (Room temperature (20℃))4.0686mm4.9502mmEFL (Low temperature (-40℃))3.9811mm4.8561mmEFL (High temperature (85℃))4.1671mm5.0559mmBFL (Room temperature (20℃))1.3499mm1.2499mmBFL (Low temperature (-40℃))1.2891mm1.1749mmBFL (High temperature (85℃))1.4087mm1.3327mmFno (Room temperature (20℃))2.082.15Fno (Low temperature (-40℃))1.9892.11Fno (High temperature (85℃))2.032.20

[0384] Mathematical formula, Example 1 of the first embodiment, Example 2 of the second embodiment 1. 2 < L1_CT / L1_ET < 2 1.485 1.772 2. 0.5 < L2_CT / L2_ET < 1.5 1.219 1.000 3. 0.5 < L3_CT / L3_ET < 1.5 0.833 1.038 4. 1.5 < n1 < 1.6 1.585 1.585 5. 20 < v1 < 30 26 26 6. 1.5 < n2 < 1.7 1.585 1.680 7. 1.2 < L3S2_max_sag to Sensor < 1.5 1.352 1.268 8. 1 < BFL / L3S2_max_sag to Sensor < 1.5 1.126 1.101 9. 10 < |L3S2_max slope| < 50 47 15 10. 1 < d23_max / d23_CT < 2 1.443 1.999 11. 0.1 < L2_CT / L1_CT < 1 0.929 0.560 12. 0.5 < L2R1 / L2R2 < 2 1.724 0.743 13. 1 < CA_L1 / CA_L2 < 1.5 1.01 1.418 14. 0.5 < CA_L2 / CA_L3 < 1 0.655 0.625 15. 0.5 < L_CT_Max / Air_Max < 2 1.661 0.858 16. 1.5 < ∑L_CT / ∑Air_CT < 3.5 3.191 1.519 17. 10 < ∑Abb / ∑Index < 20 16.404 12.578 18. 1.5 < CA_L1S1 / CA_min < 2 1.556 1.588 19. 1.5 < CA_max / CA_min < 2.5 2.301 2 20. 1 < CA_max / CA_Aver < 2 1.544 1.433 21. 0.5 < CA_min / CA_Aver < 1 0.671 0.716 22. 0.5 < CA_max / (2*ImgH) < 1 0.832 0.750 23. 1.5 < f / L1R1 < 3 1.907 2.943 24. 0.5 < EPD / L1R1 < 1.5 0.936 1.366 25. 0.1 < |f1 / f2| < 1.5 1.198 0.268 26. 5 < TTL < 6 5.392 5.986 27. 2 < ImgH < 3 2.268 2.268 28. 1.2 < BFL < 1.8 1.522 1.396 29. 3 < f < 5 4.076 4.958 30. 40 < FOV < 60 58.0548311.2 < TTL / CA_max < 1.81.4291.760322 < TTL / ImgH < 2.82.3782.639330.2 < BFL / ImgH < 0.70.6710.616343 < TTL / BFL < 53.5424.288350.5 < f / TTL < 10.7560.828362.5 < f / BFL < 42.6773.552371.5 < f / ImgH < 2.51.7972.186382 < f / EPD < 2.32.0372.155391.8 < Fno < 2.22.032.150.

[0385] Referring to Table 28, it can be seen that the optical system (1000, 1500) according to the present embodiment satisfies at least one of mathematical expressions 1 to 39. In detail, it can be seen that the optical system (1000, 1500) according to the present embodiment satisfies all of mathematical expressions 1 to 39. Accordingly, the optical system (1000, 1500) according to the present embodiment has a field of view of about 60 degrees (60±1 degrees) in a temperature range of low temperature (-40°C) to high temperature (85°C), and can have optical characteristics as shown in FIGS. 5 to 13.

[0386]

[0387] Hereinafter, with reference to FIGS. 24 to 30, a camera module that adjusts the distance between lenses or the distance between a lens and an image sensor according to temperature changes in the optical system of the present embodiment will be described. The camera module according to the present embodiment can minimize changes in performance due to temperature.

[0388] Referring to FIG. 24, a camera system according to an embodiment of the invention may include a camera module (1100), a temperature compensation unit (211) that provides a driving signal to the camera module (1100), a temperature sensor (213) that detects the ambient temperature of the camera module (1100), and a storage unit (215) that stores a compensation rate according to temperature change.

[0389] The driving unit (140) may be implemented as a first driving unit (141) that moves one lens of the second lens holder (103) in the direction of the optical axis (Lz). As another example, the driving unit (140) may be implemented as a second driving unit (151) that moves the main substrate (700) in the direction of the optical axis (Lz).

[0390] As another example, the driving unit (140) may be implemented as a third driving unit (161) that moves one lens of the first lens holder (101) in the direction of the optical axis (Lz). The driving unit (140) may be implemented as a single driving unit, but as another example, may be implemented as two or more driving units, for example, may be implemented as first and second driving units (141, 151), may be implemented as first and third driving units (141, 161), or may be implemented as second and third driving units (151, 161).

[0391] The actuator may be a VCM (Voice Coil Motor) type drive having a magnet and a coil, and may further include a supporting member, and a yoke or / and a Hall sensor may be arranged on the outside of the magnet.

[0392] The camera module (1100) may have multiple lenses (100, 200, 300) stacked along the optical axis (Lz) from the object side toward the sensor side, for example, a first lens (100), a second lens (200), and a third lens (300). The first lens (100) may be the lens closest to the object side or the first lens. The third lens (300) may be defined as the lens closest to the sensor or the last lens.

[0393] The camera module (1100) may be composed only of a plastic lens. When a plastic lens is used in a vehicle, the price can be lowered compared to a glass lens, and the incident side and the exit side can be provided aspherically, so that the light path can be easily controlled. Here, the coefficient of thermal expansion (CTE) of the plastic material is at least 5 times higher than that of the glass material, and the change value of the refractive index according to the function of temperature can be at least 10 times lower for the plastic material than for the glass material. In the case where the rate of expansion and contraction according to temperature is large, such as in the case of a plastic lens, the plastic lens (111, 112) can expand or contract according to the temperature change, as in (A) and (B) of FIG. 25, and for example, when the object-side surface is convex and / or the sensor-side surface is concave, as in (A), it can expand in the object-side direction, and when the object-side surface is concave and / or the sensor-side surface is convex, as in (B), it can expand in the sensor-side direction. These lenses (111, 112) may have different positions of the incident side and the exit side or different heights of the optical axis (Lz). Accordingly, the lenses (111, 112) may have their optical characteristics affected by temperature changes.

[0394] The first lens holder (101) may be made of plastic or metal for heat dissipation efficiency. The second lens holder (103) may be made of plastic or metal for heat dissipation efficiency. If the lens holders (101, 103) are made of metal, the heat dissipation effect of the camera module (1100) can be improved, or if the same material as the plastic lens is used, the difference in thermal expansion coefficient can be reduced. The metal material may be selected from among Al, Ag, or Cu, and may be Al or an Al alloy. A hydrophilic material may be coated or applied to the surfaces of the first and second lens holders (101, 103). In an embodiment of the invention, the material of the second lens holder (103) may be metal for BFL compensation.

[0395] Each of the lenses (100, 200, 300) may include an effective area having an effective diameter through which light is incident and a flange, which is a non-effective area, outside the effective area. The non-effective area may be an area where light is blocked by a light shield (131, 133). The flange may extend circumferentially with respect to the optical axis (Lz) in the effective area of ​​the lens (100, 200, 300). At least one of the lenses (100, 200, 300) may have no flange portion or may be provided with a relatively short length. The third lens (300) may have a flange (117A) on its outer periphery that is coupled to the inner side of the second lens holder (103).

[0396]

[0397] The temperature sensor (213) can detect the ambient temperature of the camera module (1100). The detected temperature can detect the temperature inside or outside the camera module (1100), and can be detected in a range of -50 degrees to 125 degrees. The camera module (1100) can be applied to a mobile device such as a vehicle, an airplane, a ship, or a mobile terminal. For example, in the case of a vehicle, the temperature deviation may be large depending on the external environment. In this case, the reference temperature may be the temperature inside the vehicle.

[0398] The temperature compensation unit (211) controls the driving mode of the driving unit(s) based on the temperature detected from the temperature sensor (213). The storage unit (215) can store the detected temperature and the temperature compensation rate according to the temperature in a matching manner.

[0399] For example, as shown in Fig. 27, the temperature compensation rate by section can be set to a first mode (Status 1-3) for compensating when the temperature is lower than the reference (Ref) temperature based on the reference temperature, and a second mode (Status 5-8) for compensating when the temperature is higher than the reference (Ref) temperature. The reference (Ref) temperature can be an indoor temperature, for example, a range of 10 to 30 degrees or a range of 15 to 25 degrees, and preferably 20 degrees ± 10 degrees. The first mode (Status 1-3) is a temperature lower than the reference (Ref) temperature, and the temperature for each section can be divided into at least three sections ranging from 10 degrees to -50 degrees, the first section (Status 1) can be in the range of 10 to -10 degrees, the second section (Status 2) can be in the range of -10 to -30 degrees, and the third section (Status 3) can be in the range of -30 to -50 degrees. The reference temperatures for each section of the first to third sections (Status 1-3) can be 0 degrees, -20 degrees, and -40 degrees, and the temperature deviation for each section can be ±10 degrees. The second mode is a temperature higher than the reference (Ref) temperature, and the temperature by section can be divided into at least four sections ranging from 30 degrees to 100 degrees. Looking at the temperature by section, the first section (Status 5) has a range of 30 to 50 degrees, the second section (Status 6) has a range of 50 to 70 degrees, the third section (Status 7) has a range of 70 to 90 degrees, and the fourth section (Status 8) can have a range of 90 to 110 degrees. The reference temperatures by section of the first to fourth sections (Status 5-8) can be 40 degrees, 60 degrees, 80 degrees, and 100 degrees, and the deviation of the temperature by section can be ±10 degrees.

[0400] Another example of the invention is that the temperature correction rate for each section can be corrected by the average temperature change amount of each section (status 1-8). For example, in the first section (Status 1) lower than the reference temperature, the temperature correction rate can be set to the average value of the temperature correction rate of 10 degrees and the temperature correction rate of -10 degrees, and in this manner, the average temperature correction rate of each of the second to third sections lower than the reference temperature can be set. In addition, in the first section (Status 5) higher than the reference temperature, the temperature correction rate of the section can be set to the average value of the temperature correction rate of 30 degrees and the temperature correction rate of 50 degrees, and in this manner, the average temperature correction rate of each of the second to fourth sections higher than the reference temperature can be corrected.

[0401] Another example of the invention is that, in calculating the average temperature correction rate, in each section lower than the reference temperature, a correction rate with a relatively low temperature can be given more weight, and in each section higher than the reference temperature, a correction rate with a relatively high temperature can be given more weight. For example, in the first section (Status 1) lower than the reference temperature, a temperature correction rate of 10 degrees can be given a weight of 30%, a temperature correction rate of -10 degrees can be given a weight of 70%, and the temperature correction rate can be set as the average value of these, and in this way, the average temperature correction rate with the added weights of the second to third sections lower than the reference temperature can be set. In addition, in the first section (Status 5) higher than the reference temperature, a temperature correction rate of 30 degrees can be given a weight of 30%, a temperature correction rate of 50 degrees can be given a weight of 70%, and the temperature correction rate of the corresponding section can be set as the average value of these, and in this way, the average temperature correction rate of the second to fourth sections higher than the reference temperature can be compensated for.

[0402] The temperature compensation unit (211) can determine the driving mode based on the temperature match by comparing the detected temperature with the reference mode stored in the storage unit (215), the temperature compensation rate for each section (Status 1-3) of the first mode, and the temperature compensation rate for each section (Status 1-3) of the second mode. Alternatively, the temperature compensation unit (211) can control the position of the BFL based on the average temperature compensation rate for each section.

[0403] The temperature compensation unit (211) can control at least one driving unit (141, 151, 161) according to the driving mode. For example, when the first driving unit (141) is driven by the first control signal (F1), the optical axis (Lz) distance between the sensor side of the third lens (300) and the image sensor (600), i.e., the back focal length (BFL), can be increased or decreased. Preferably, since the third lens (300) contracts or expands according to temperature change, the reference BFL can be decreased or increased.

[0404] In a certain section, the third lens (300) may contract, thereby increasing the BFL from a reference value, and the temperature compensation unit (211) may control the driving unit (141, 151) so that the BFL increases according to the temperature compensation rate of the BFL. Conversely, in a certain section of the second mode in which the detected temperature is higher than the reference temperature, the temperature compensation unit (211) may control the first driving unit (141, 151) so that the BFL decreases according to the temperature compensation rate of the BFL.

[0405] When a first control signal (F1) is input, the first driving unit (141) can move the third lens (300) up or down in the direction of the optical axis (Lz). When a second control signal (F2) is input, the second driving unit (151) can move the main board (700) up or down in the direction of the optical axis (Lz). When a third control signal (F3) is input, the third driving unit (161) can move the first lens holder (101) or any one of the internal lenses (100, 200, 300) up or down in the direction of the optical axis (Lz). Here, when the third driving unit (161) is driven, the change in the TTL (Total track length) of the camera module (1100) can be controlled according to a temperature change, or the TTL can be reduced or increased according to a BFL change. TTL is the optical axis (Lz) distance from the object side of the first lens (100) to the image sensor (600).

[0406] As shown in Fig. 28, the embodiment of the invention drives the first or second driving unit (141, 151) to increase or decrease the BFL according to the temperature change or BFL change of the last lens (300) within a region connecting the point of at least -5% and the point of at most -14.3% when the temperature is at a minimum of -40 degrees Celsius, and the point of at least 5% and the point of at least 14.3% when the temperature is at a maximum of 100 degrees Celsius, thereby maintaining a constant reference BFL. Accordingly, the change in the optical performance of the camera module due to the change in temperature can be suppressed.

[0407] When a control signal is input based on the temperature detected by the temperature compensation unit (211), the first and second actuators (141A, 141B) move the magnets (41) up or down in the direction of the optical axis (Lz) together with the second lens holder (103) due to the electromagnetic influence between the coil (42) and the magnet (41). At this time, the spring member (45) supports the movement of the second lens holder (103) in the direction of the optical axis (Lz), and the optical axis distance (BFL) between the lens (L3) of the second lens holder (103) and the image sensor (600) increases or decreases. Therefore, the distance (BFL) between the last lens (L3) of the second lens holder (103) and the image sensor (600) can be maintained constant even if the last lens (L3) expands or contracts due to temperature. Accordingly, the camera module (1100) can suppress changes in optical performance even if the temperature varies due to the configuration.

[0408] Referring to FIG. 30, the BFL compensation method by the temperature compensation unit (211) detects the ambient temperature of the camera module (1100) by the temperature sensor (213) (S1), and compares and matches the detected ambient temperature with the temperature compensation table stored in the storage unit (215) (S2). At this time, if the ambient temperature is in the reference mode, the method may proceed to the step of controlling to maintain the reference BFL (S3), providing driving force to the first or second driving unit (141, 151) of the camera module so that the BFL increases if the first temperature is lower than the reference temperature (S4), and providing driving force to the first or second driving unit (141, 151) of the camera module so that the BFL decreases if the second temperature is higher than the reference temperature (S5).

[0409]

[0410] Those skilled in the art will appreciate that the present invention can be implemented in modified forms without departing from the essential characteristics of the above-described description. Therefore, the disclosed methods should be considered illustrative rather than restrictive. The scope of the present invention is set forth in the claims, not the foregoing description, and all differences within the scope equivalent thereto should be construed as being encompassed by the present invention.

Claims

1. A first lens having positive (+) refractive power; second lens; and Including a third lens having negative (-) refractive power, The first to third lenses are arranged sequentially from the object side to the image side, Including an aperture arranged between the first lens and the second lens, An optical system wherein the distance between the first lens and the second lens on the optical axis is greater than the thickness of the third lens.

2. A first lens having positive (+) refractive power; a second lens having negative (-) refractive power; and Including a third lens having positive (+) refractive power, The first to third lenses are arranged sequentially from the object side to the image side, Including an aperture arranged between the first lens and the second lens, An optical system in which the thickness of the third lens on the optical axis is greater than the thickness of the first lens.

3. In paragraph 1 or 2, An optical system in which the third lens has a meniscus shape convex toward the object side on the optical axis.

4. In paragraph 1 or 2, An optical system in which the second lens has a convex meniscus shape toward the sensor in the optical axis.

5. In paragraph 1 or 2, An optical system wherein the distance between the first lens and the second lens on the optical axis is greater than the distance between the second lens and the third lens.

6. In paragraph 1 or 2, An optical system wherein the thickness of the second lens on the optical axis is greater than the gap between the second lens and the third lens.

7. In paragraph 1 or 2, An optical system that satisfies the following conditions: <Conditional expression> 3 < f < 5 (In the above conditional expression, f means the total focal length of the optical system.) 8. In paragraph 1 or 2, An optical system that satisfies the following conditions: <Conditional expression> 1.8 < Fno < 2.2 (In the above conditional expression, Fno means the F-number of the optical system.) 9. In paragraph 1 or 2, An optical system that satisfies the following conditions: <Conditional expression> 1.5 < n1 < 1.6 (In the above conditional expression, n1 represents the refractive index of the first lens.) 10. In paragraph 1 or 2, An optical system that satisfies the following conditions: <Conditional expression> 20 < v1 < 30 (In the above conditional expression, v1 represents the Abbe number of the first lens.)

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