KR20220145212A - Inspection optical system and inspection device of camera module - Google Patents

Abstract

The present invention is to provide an inspection optical system capable of inspecting the resolution of a camera module according to an object distance without moving the optical system by using a telecentric optical system. An inspection optical system disclosed in an embodiment of the present invention includes a first inspection optical unit having a plurality of lenses aligned along an optical axis from an object side to a sensor side; and a second inspection optical unit disposed between the first inspection optical unit and a camera module to be tested and having a plurality of lenses, wherein the lenses of the first inspection optical unit and the second inspection optical unit have symmetrical shapes and arrangements at a center between the first inspection optical unit and the second inspection optical unit, and each of the first and second inspection optical units may be a telecentric optical system.

Description

Inspection optical system and camera module inspection device having the same

The embodiment relates to an inspection optical system for a camera module and a camera module inspection apparatus having the same.

In recent years, as products equipped with mega-pixel cameras have been released on most mobile communication terminals, the rapid growth of the camera-mounted mobile phone market and consumers demanding higher resolution and higher image quality for moving images including still images. demand is gradually increasing.

Accordingly, in addition to the basic shooting function of the camera mounted in the mobile phone, a multi-functional mobile phone that can be implemented in a complex manner, such as an autofocus (AF) control function, macro, and optical zoom functions, is being developed. , a system for evaluating and inspecting the quality of the camera module mounted on the mobile phone according to the manufacturer's standards is required.

One established and useful method for determining the imaging quality of an optical imaging system is measurement of the modulation transfer function (MTF). However, the conventional inspection equipment using the collimator lens optical system cannot measure the near and far distances at the same time with a fixed object distance, MTF measurement is not possible through focus, there is a problem of tilt verification and epoxy shrinkage in the camera module, and the object distance There is a problem in that the lens aperture is increased according to the .

An embodiment of the present invention is to provide an inspection optical system capable of examining the resolution according to the object distance of a camera module without movement of the optical system using a telecentric optical system.

An embodiment of the present invention is to provide a camera module inspection apparatus in which a telecentric optical system is symmetrically arranged.

An inspection optical system according to an embodiment of the present invention includes: a first inspection optical unit having a plurality of lenses aligned with an optical axis from an object side to a sensor side; and a second inspection optical unit disposed between the first inspection optical unit and a camera module to be tested and having a plurality of lenses, wherein the lenses of the first inspection optical unit and the second inspection optical unit are the first inspection optical unit A shape and arrangement symmetrical to each other in a central portion between the and the second inspection optical unit may be provided, and each of the first and second inspection optical units may be a telecentric optical system.

According to an embodiment of the present invention, each of the first and second inspection optical units may have 9 or 10 lenses.

According to an embodiment of the present invention, the diameter of the lenses of the first inspection optical unit may gradually increase from the object side to the sensor side, and the diameters of the lenses of the second inspection optical unit may gradually decrease from the object side to the sensor side.

According to an embodiment of the present invention, the lens closest to the object side or the first inspection optical unit in the second inspection optical unit may have a meniscus shape convex toward the object side.

According to an embodiment of the present invention, the lens furthest from the sensor side or the first inspection optical unit in the second inspection optical unit may have a meniscus shape convex toward the object.

According to an embodiment of the invention, the second inspection optical unit satisfies the following Equation 1,

[Equation 1] 0.1 ≤ ｜L2/TL｜ ≤0.5

L2 is the optical axis distance between the sensor-side second surface of the first lens closest to the object side and the object-side third surface of the second lens adjacent thereto, and TL is the camera at the object-side first surface of the first lens It is the optical axis distance to the sensor side of the lens closest to the module.

According to an embodiment of the invention, the second inspection optical unit satisfies the following Equation 2,

[Equation 2] 0.4 ≤ ｜Yobj/D1｜ ≤ 0.5

The D1 may be the diameter of the first lens closest to the object side, and Yobj may be the maximum image height with respect to the object.

According to an embodiment of the invention, the second inspection optical unit satisfies the following Equation 3,

[Equation 3] 0.0 ≤ ｜L0/TL｜ ≤0.3

When the virtual image distance is infinity, L0 may be a distance from the center to the first object-side surface of the first lens, and TL may be the total optical axis distance of the second inspection optical unit.

According to an embodiment of the present invention, the angle between the chief ray and the optical axis at the maximum image height of the object in the second inspection optical unit may be 1 degree or less.

An apparatus for inspecting a camera module according to an embodiment of the present invention includes: an electronic chart unit having a light source and an electronic chart; a camera module having a lens optical system and an image sensor; and the inspection optical system disposed between the electronic chart unit and the camera module and condensing the light rays passing through the electronic chart on the camera module.

According to an embodiment of the present invention, distortion of the optical system can be canceled by symmetrically disposing the same telecentric optical system. Also, it is possible to check the performance change according to the change in the object distance by moving the small electronic chart to the minimum. In addition, it is possible to check whether the fixed karema module is tilted, and it is possible to check whether the epoxy shrinkage is changed.

1 is a perspective view of a mobile terminal having a plurality of camera modules according to an embodiment of the present invention.
2 is a view showing a camera module inspection apparatus according to a first embodiment of the present invention.
FIG. 3 is a configuration diagram of the inspection optical system of FIG. 2 .
4A and 4B are diagrams illustrating the virtual image position at a distance of 10 cm or at infinity by the inspection optical system of FIG. 3 .
FIG. 5 is a detailed configuration diagram of the second inspection optical unit of FIG. 3 .
6A and 6B are examples of optical paths at 10 cm and -10 cm in the second inspection optics of the present invention.
7 is a view showing a second inspection optical unit of the camera module inspection apparatus according to the second embodiment of the present invention.
8 is a view showing a second inspection optical unit of the camera module inspection apparatus according to the third embodiment of the present invention.
9 is a view showing a second inspection optical unit of the camera module inspection apparatus according to the fourth embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

However, the technical spirit of the present invention is not limited to some embodiments described, but may be implemented in various different forms, and within the scope of the technical spirit of the present invention, one or more of the components may be selected between the embodiments. It can be combined and substituted for use. In addition, terms (including technical and scientific terms) used in the embodiments of the present invention may be generally understood by those of ordinary skill in the art to which the present invention pertains, unless specifically defined and described explicitly. It may be interpreted as a meaning, and generally used terms such as terms defined in advance may be interpreted in consideration of the contextual meaning of the related art. In addition, the terms used in the embodiments of the present invention are for describing the embodiments and are not intended to limit the present invention. In this specification, the singular form may also include the plural form unless otherwise specified in the phrase, and when it is described as "at least one (or one or more) of A and (and) B, C", it is combined with A, B, C It may include one or more of all possible combinations. In addition, in describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the component from other components, and are not limited to the essence, order, or order of the component by the term. And, when it is described that a component is 'connected', 'coupled' or 'connected' to another component, the component is not only directly connected, coupled or connected to the other component, but also with the component It may also include a case of 'connected', 'coupled' or 'connected' due to another element between the other elements.

In addition, when it is described as being formed or disposed on "upper (above) or under (below)" of each component, upper (above) or lower (below) is not only when two components are in direct contact with each other, but also Also includes cases in which one or more other components are formed or disposed between two components. In addition, when expressed as "up (up) or down (down)", the meaning of not only the upward direction but also the downward direction based on one component may be included.

In the description of the invention, the first lens means the lens closest to the object side, and the last lens means the lens closest to the image side (or sensor surface). Unless otherwise stated in the description of the invention, the units for the radius, effective diameter, thickness, distance, BFL (Back Focal Length), TTL (Total Track Length or Total Top Length), etc. of the lens are all mm. In the present specification, the shape of the lens is shown based on the optical axis of the lens. For example, the meaning that the object side of the lens is convex means that the vicinity of the optical axis is convex on the object side of the lens, but does not mean that the vicinity of the optical axis is convex. Accordingly, even when it is described that the object side of the lens is convex, the portion around the optical axis on the object side of the lens may be concave. In the present specification, it should be noted that the thickness and radius of curvature of the lens are measured based on the optical axis of the lens. In addition, "object-side surface" may refer to the surface of the lens facing the object side with respect to the optical axis, and "image side" refers to the surface of the lens facing the imaging surface with respect to the optical axis. can do.

Referring to FIG. 1 , the camera module 711 of the mobile terminal may be coupled to the case 700 of the mobile terminal. In the camera module 711 , a plurality of lens modules 712 , 732 , and 752 are arranged in first and second directions, and at least one or all of the lens modules may be vertically up or down. A ToF lens module 772 may be added or a camera flash module may be further disposed within the camera module 711 , but the present disclosure is not limited thereto. A part of the lens module may protrude from the case 700 of the terminal.

Here, when assembling the camera module 711, automatic focusing is checked using a driving unit such as an actuator in three or more lens modules 712, 732, 752. The lens module is fixed to the focusing position without At this time, the lens optical system is attached to the image sensor without a driving unit. When the lens optical system is attached with an adhesive such as epoxy, the focusing position may be changed when the adhesive is contracted or tilted, which causes the focusing distance to change or the angle of view to change. There is a growing distortion problem. In an embodiment of the invention, by disposing the telecentric optical system symmetrically to each other, it is possible to measure both the near and far distances at the same time, and it is possible to check whether the camera module with a fixed focusing is tilted, and whether or not to change due to the shrinkage of the adhesive such as epoxy. By checking in advance, it can be inspected so that the lens optical system can be installed on the image sensor at a more accurate position. To this end, when a lens optical system having a fixed focus is installed on the image sensor, an error may be corrected after inspection using a camera module inspection apparatus.

2 is a configuration diagram of a camera module inspection apparatus according to an embodiment of the invention, FIG. 3 is a configuration diagram of the inspection optical system of FIG. 2 according to a first embodiment of the invention, and FIGS. It is a view showing the virtual image position at 10 cm or infinity distance by the inspection optical system of 3, FIG. 5 is a detailed configuration diagram of the second inspection optical unit of FIG. 2 Examples of optical paths at 10 cm and -10 cm in the inspection optic.

2 and 3 , the camera module inspection apparatus may include an electronic chart unit 100 , an inspection optical system 200 , and a camera module 300 to be tested.

The electronic chart unit 100 includes a light source 110 and an electronic chart 120 , and light rays emitted from the light source 110 pass through the inspection optical system 200 through the electronic chart 120 . The electronic chart unit 100 may be moved to the object side or the sensor side based on the optical axis according to a preset measurement distance. The preset measurement distance is a moving distance set as the focusing position from a short distance (eg, 10 cm) to infinity. The light source 110 may include an LED, laser, LCD, organic EL, or the like that emits ultraviolet or visible light. In the electronic chart 120 , a predetermined pattern is emitted through the light source 110 when power is applied, and, for example, a pattern for focusing adjustment may be sequentially displayed. According to an embodiment of the present invention, by moving the light source 110 of the single electronic chart unit 100 , a long-distance function evaluation and a short-distance function evaluation for focusing of the camera module 300 may be performed.

The inspection optical system 200 may include a first inspection optical unit 210 and a second inspection optical unit 220 . The inspection optical system 200 includes an optical system that converts an object at a finite distance into a virtual image, and is disposed between the electronic chart unit 100 and the camera module 300 and is assembled of the camera module 300 . Autofocus adjustment can be performed.

The first inspection optical unit 210 and the second inspection optical unit 220 may include an optical system in which the shape, size, and arrangement distance of each lens are symmetrical to each other with respect to the center Zc. Each of the first inspection optical unit 210 and the second inspection optical unit 220 may be a telecentric optical system. Here, the telecentric optical system is an optical system that minimizes the projection of objects having different sizes due to the difference in distance, and can cancel distortion characteristics by using two symmetrical telecentric optical systems. In addition, distortion of the first and second inspection optical units 210 and 220 symmetrical from the center Zc can be canceled without moving the telecentric optical system. All of the first and second inspection optical units 210 and 220 may function as a collimator optical system. The inspection optical system 200 may verify the optimally focused lens position at the same distance due to a deviation of a lens mounted for each camera module and a tilt or rotation deviation that may occur during assembly.

The first inspection optical unit 210 is disposed between the electronic chart unit 100 and the second inspection optical unit 220, and may include 9 or 10 lenses. The first inspection optical unit 210 may be a full lens group or a first lens group. In the first inspection optical unit 210 , a plurality of lenses 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 and 20 may be aligned along an optical axis.

The second inspection optical unit 220 may be disposed between the first inspection optical unit 210 and the camera module 300 for testing, and may include a 9- or 10-element lens. The second inspection optical unit 220 may be a rear lens group or a second lens group. In the second inspection optical unit 220 , a plurality of lenses 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 and 30 may be aligned along an optical axis.

The first lens 11 closest to the object side in the first inspection optical unit 210 may be a lens having the smallest diameter, and the last tenth lens 20 may be a lens having the largest diameter. The first lens 21 closest to the center of the second inspection optical unit 220 may be a lens having the largest diameter, and the tenth lens 30 closest to the sensory side may be a lens having the smallest diameter. . The diameter of each lens of the first inspection optical unit 210 may gradually increase from the object side toward the sensor side. The diameter of each lens of the second inspection optical unit 220 may gradually decrease from the object side toward the sensor side. The diameter may be an effective diameter through which the light beam travels.

Based on the center Zc between the first and second inspection optical units 210 and 220 , the lenses 11-20 of the first inspection optical unit 210 and the lenses of the second inspection optical unit 220 are (21-30) may be aligned in a symmetrical shape with each other along the optical axis.

The camera module 300 may include a lens optical system 310 and an image sensor 320 as a test object, and the lens optical system 310 may be implemented without an actuator for focusing. The lens optical system 310 may be a fixed optical system without movement in the optical axis direction. The image evaluation apparatus moves the electronic chart unit 100 and provides light through the inspection optical system 200 to detect the focusing position of the lens optical system 310 from a distance to a short distance received by the image sensor 320, and , it is possible to adjust the amount or tilt of the adhesive according to the focusing position by using the detection information.

Referring to FIG. 3 , as shown in (A), when the object distance of the first inspection optical unit 210 is 10 cm and the object distance of the second inspection optical unit 220 is -10 cm, the virtual image position is the second It may be formed between the fifth and sixth lenses 25 and 26 of the inspection optical unit 220 . Here, (A) (B) of FIG. 6 is a view showing an optical path when the object distance is 10 cm and -10 cm in the second inspection optical system 220 . As shown in FIG. 3B , when the object distance of the first and second inspection optical units 210 and 220 is infinite, the virtual image position may be formed in the center Zc of the first and second inspection optical units 210 and 220 . have. Here, the point 201 at which light is incident on the first inspection optical unit 210 may be a point at which light is emitted from the electronic chart unit 100 , and the light is condensed through the second inspection optical unit 220 . The point 203 may be a point in contact with the lens optical system 310 of the camera module 300 or a stop position that is an aperture of the inspection optical system 200 .

Hereinafter, since the first and second inspection optical units 210 and 220 are arranged in a structure in which lenses have the same shape and arrangement, the second inspection optical unit 220 will be mainly described.

3 and 5 , in the second inspection optical unit 220 , the object-side first surface S1 of the first lens 21 closest to the object side is convex, and the sensor-side second surface ( S2) may be concave, may have a meniscus shape convex toward the object side, and may have positive refractive power. The first lens 21 closest to the object side may be provided in a meniscus shape to correct coma aberration.

The optical axis distance L2 between the sensor-side second surface S2 of the first lens 21 closest to the object side and the object-side third surface S3 of the second lens 22 adjacent thereto; The relationship between the optical axis distance TL from the object-side first surface S1 of the lens 21 to the sensor-side twentieth surface S20 of the last tenth lens 30 may satisfy Equation 1 below.

[Formula 1]

0.1 ≤ ｜L2/TL｜ ≤0.5

Here, Equation 1 is a condition to have a diameter of the telecentric optical system. If it is larger than the above range, the diameter of the lens located after the second lens 22 may be increased, and if it is smaller than the above range, the second lens 22 ) has too large refractive power, so it is difficult to correct aberration.

[Equation 2]

0.4 ≤ ｜Yobj/D1｜ ≤ 0.5

Here, D1 is the diameter of the lens 21 closest to the object side, and Yobj is the maximum image height of the optical system with respect to the object. In order for the second inspection optical unit 220 to be telecentric, the diameter of the first lens 21 closest to the object side must be greater than the object size, and if Equation 2 is greater than the above range, telecentricity cannot be implemented, When it is smaller than the above range, a problem in which the diameter of the first lens 21 becomes too large may occur.

[Equation 3]

0.0 ≤ ｜L0/TL｜ ≤0.3

Here, when the virtual image distance is infinity, L0 is the distance from the center Zc to the object-side first surface S1 of the first lens 21 , and TL is the entire optical axis of the second inspection optical unit 220 . is the street Equation 3 is a telecentric condition of the second inspection optical unit 220. If Equation 3 is larger than the above range, the diameter of the first lens 21 is increased, and if smaller than the above range, the center Zc and Since the first lens 21 is too close, there is a problem in that it is difficult to measure the resolution of the optical system.

The following Equation 4 is satisfied in order to measure the resolution according to the change in the distance between the lens optical system 310 for the mobile terminal and the object.

[Equation 4]

0.5 ≤ ｜Omax/F｜ ≤ 1

Here, Equation 4 is used to define the object distance change, where Omax is the maximum object distance (distance from the center) that can be changed in the second inspection optical unit 220 , and F is the focus of the second inspection optical unit 220 . is the street In Equation 4, when the range is larger than the above range, the aberration characteristic of the second inspection optical unit 220 is increased.

Also, the tenth lens 30, which is the last in the second inspection optical unit 220, may have a meniscus shape convex in the object direction. The shape of the tenth lens 30 may be a coma correction condition by the first lens 21 . That is, both the first lens 21 and the tenth lens 30 may have a meniscus shape convex in the object direction. In this case, since the first inspection optical unit 210 has a symmetrical shape with the second inspection optical unit 220 , both the first lens 21 and the tenth lens 30 may have a meniscus shape convex in the sensor direction. have.

Here, for the telecentric condition of the second inspection optical unit 220 , the angle between the chief ray and the optical axis at the maximum image height of the object of the second inspection optical unit 220 may be 1 degree or less. Here, when the angle exceeds 1 degree, an image occlusion phenomenon or aberration of the optical system itself increases rapidly.

The inspection apparatus having the first and second inspection optical units 210 and 220 according to an embodiment of the present invention moves the electronic chart unit 100, not the large-aperture lens constituting the collimator, to detect the focusing position from a distance to infinity. It is possible to minimize the moving time of the electronic chart unit 100, and it is possible to implement a fast inspection speed.

The first inspection optical unit 210 may have a symmetrical shape and a symmetrical arrangement with the second inspection optical unit 220 . In the first embodiment, each of the first inspection optical unit 210 and the second inspection optical unit 220 may include 10 lenses. Each of the first and second inspection optical units 210 and 220 may include first to tenth lenses 11 to 20 and 21 to 30 .

The first lens 11 of the first inspection optical unit 210 and the tenth lens 30 of the second inspection optical unit 220 have a symmetrical shape to each other, and the first lens 11 of the first inspection optical unit 210 is The second lens 12 and the ninth lens 19 of the second inspection optical unit 220 may be symmetrical to each other, and the third, 4, 5, 6, 7, The 8 and 9 lenses 13, 14, 15, 16, 17, 18, 19 are the 8, 7, 6, 5, 4, 3, 2 lenses 28, 27, 26 of the second inspection optical unit 220 . , 25, 25, 24, 22) and may have a symmetrical shape, respectively, and the tenth lens 20 of the first inspection optical unit 210 is the first lens 21 of the second inspection optical unit 220 . It may be adjacent to and symmetrical to each other. In the second inspection optical unit 220 , the first lens 21 is the lens closest to the object side, and the tenth lens 30 is the lens closest to the sensor side.

The second inspection optical unit 220 is an optical system for changing a virtual image of an object located at a finite distance, and may have a telecentric surface on the object side. On the optical axis passing through the center of each lens, the concave or convex structures of the first lens 21 to the tenth lens 30 are as follows.

The first lens 21 may be closest to the first inspection optical unit 210 , the object-side first surface S1 may be convex, and the sensor-side second surface S2 may be concave. The second lens 22 is disposed between the first lens 21 and the third lens 23 , and both the object-side third surface S3 and the sensor-side fourth surface S4 may be convex. The distance L2 between the first and second lenses 21 and 22 may be the largest in the first inspection optical unit 210 .

The third lens 23 may be disposed between the second and fourth lenses 22 and 24 , and the fifth surface S5 on the object side may be convex and the sixth surface S6 on the sensor side may be concave. The fourth lens 24 is disposed between the third and fifth lenses 23 and 25 , and the object-side seventh surface S7 may be convex and the sensor-side eighth surface S8 may be concave. The fifth lens 25 is disposed between the fourth and sixth lenses 24 and 26 , the object-side ninth surface S9 and the sensor-side tenth surface S10 may be convex, and the sixth lens 26 . ) is disposed between the fifth and seventh lenses 25 and 27, and the object-side eleventh surface S11 may be concave and the sensor-side twelfth surface S12 may be concave.

The seventh lens 27 is disposed between the sixth and eighth lenses 26 and 28, the object-side thirteenth surface S13 may be convex, and the sensor-side fourteenth surface S14 may be concave, and the eighth lens 27 may be convex. The lens 26 is disposed between the seventh and ninth lenses 27 and 29 , and the object-side fifteenth surface S15 may be convex and the sensor-side sixteenth surface S16 may be concave.

The ninth lens 29 is disposed between the eighth and tenth lenses 29 and 30, the object-side 17th surface S17 may be convex, the sensor-side 18th surface S18 may be concave, and the tenth lens Reference numeral 30 denotes a lens closest to the camera module 300 , and the object-side 19th surface S19 may be convex and the sensor-side 20th surface S20 may be concave. Hereinafter, it will be described based on the second inspection optical unit 220 , and the lenses 11-20 of the first inspection optical unit 210 are the lenses 21-30 of the second inspection optical unit 220 . Please refer to the description.

As shown in FIG. 5 , the lens data of the second inspection optical unit 220 according to the first embodiment are as follows.

Looking at the center thickness, among the lenses, the third lens 23 , the sixth lens 26 , and the ninth lens 29 may have a center thickness of 10 mm or less, for example, 3 mm to 10 mm, and the ninth lens < The condition of the sixth lens < the third lens may be satisfied. The tenth lens 30 has a thickness in the range of 10 mm to 20 mm, and the second lens 22 , the fourth lens 24 , the fifth lens 25 , the seventh lens 27 , and the eighth lens 28 . The thickness of may be 21 mm or more, for example, 21 mm to less than 40 mm, of which the thickness of the second lens 22 , the fourth lens 24 , and the fifth lens 25 may be 30 mm or more. The thickness of the tenth lens 30 may be greater than the thickness of the third lens 23 , the sixth lens 26 , and the ninth lens 29 .

Looking at the radius of curvature, when expressed in absolute values, the second surface S1 of the first lens 21 , the fourth surface S4 of the second lens 22 , and the fifth surface ( S4 ) of the third lens 23 ( S5) and the twelfth surface S12 of the sixth lens 26 may be 750 mm or more, for example, in the range of 750 mm to 1100 mm, and the fifteenth surface S15 and the ninth lens of the eighth lens 28 . The 18th surface S18 of (29), the 19th surface S19 and the 20th surface S20 of the tenth lens 30 may be less than 100 mm, and may be in the range of 30 mm to 100 mm.

Looking at the refractive index, the refractive index Nd of the first, 8 and 10 lenses 21, 28, 30 is higher than that of the other lenses and is 1.9 or more, and the second, 4, 5, 7, 9 lenses 22 and 24 .

Looking at the Abbe numbers (Vd), the second, 4, 5, and 7 lenses 22, 24, 25, 27 have an Abbe number of 70 or more higher than the Abbe numbers of the other lenses, and the first, 3, 6, 8, 9, 10 The lenses 21 , 23 , 26 , 28 , 29 and 30 may be 50 or less.

As for the lens diameter or half aperture of the second inspection optical unit 220 , the object-side first surface S1 of the first lens 21 is the largest, and the first lens 21 in the sensor direction It gradually becomes smaller up to the tenth lens 30 , and the sensor-side twentieth surface S20 of the tenth lens 30 may be the smallest.

An example of the lens data of the second inspection optical unit 220 is shown in Table 1.

lens noodle radius of curvature thickness/thickness refractive index Abbesu hemispherical first lens S1 402.639 25.000 2.00069 25.46 138.4 S2 992.244 115.000 136.66 second lens S3 293.930 35.000 1.45860 90.19 109.56 S4 -841.642 0.300 107.69 third lens S5 990.953 6.000 1.76182 26.61 101.45 S6 128.683 0.960 89.74 4th lens S7 125.866 36.000 1.49700 81.61 90.12 S8 466.546 0.300 88.63 5th lens S9 205.161 36.500 1.45860 90.19 85.98 S10 -300.695 2.054 84.25 6th lens S11 -280.204 5.000 1.84666 23.78 83.1 S12 985.840 8.345 79.83 7th lens S13 100.501 30.000 1.45860 90.19 71.92 S14 529.952 0.300 70.01 8th lens S15 80.663 28.000 2.00069 25.46 57.75 S16 111.330 7.015 46.62 9th lens S17 225.197 4.000 1.59270 35.45 44.86 S18 40.665 4.566 32.89 10th lens S19 44.938 14.845 2.00069 25.46 32.22 S20 60.584 30.700 26.83 Stop infinity 0.000 2 Image infinity 0.000

In Table 1, the stop-in diaphragm position may be the object-side surface closest to the object-side of the lens optical system 310, and the lens optical system 310 has an effective focal length of 4 mm.

Table 2 below is data on object distances from infinity to 100 mm and -100 mm at infinity according to the first embodiment, where D0 is a chart position in the second inspection optic, and D2 is in the second inspection optic. It is the effective focal length according to the object distance change, and the MAG value is the image size/object size value.

Config infinity 100 mm -100 mm DO 20 -251.5028 287.0986 D2 4 4.16667 3.84618 MAG 0.02437 0.02518 0.02363

Referring to FIG. 7 , the second inspection optical unit 230 according to the second embodiment includes 10 lenses. Accordingly, in the inspection optical system 200 of FIG. 2 according to the second embodiment, the first and second inspection optical units 210 and 230 may be formed of 10 lenses. The lenses of the first inspection optical unit 210 and the lenses of the second inspection optical unit 230 may have a symmetrical shape with respect to the central portion Zc, and may have a symmetrical arrangement. This second embodiment will be described based on the second inspection optical unit 230 , and the first inspection optical unit 210 will refer to the second inspection optical unit 230 , and the relationship of Equations 1 to 4 will be applied. can be satisfied

The second inspection optical unit 230 is an optical system for changing a virtual image of an object located at a finite distance, and may have a telecentric surface on the object side. On the optical axis passing through the center of each lens, the concave or convex structures of the first to ninth lenses are as follows.

The first lens 31 may be closest to the symmetrical first inspection optical unit, and the object-side first surface S1 may be convex, and the sensor-side second surface S2 may be concave. The first lens 31 may have a meniscus shape convex in the object direction.

The second lens 32 is disposed between the first lens 31 and the third lens 33 , and both the object-side third surface S3 and the sensor-side fourth surface S4 may be convex. The optical axis distance L2 between the first and second lenses 31 and 32 may be the largest in the first inspection optical unit.

The third lens 33 may be disposed between the second and fourth lenses 32 and 34 , and the object-side fifth surface S5 may be concave, and the sensor-side sixth surface S6 may be concave. The fourth lens 34 is disposed between the third and fifth lenses 33 and 35 , and the object-side seventh surface S7 may be convex and the sensor-side eighth surface S8 may be concave. The fifth lens 35 is disposed between the fourth and sixth lenses 34 and 36 , the object-side ninth surface S9 and the sensor-side tenth surface S10 may be convex, and the sixth lens 36 . ) is disposed between the fifth and seventh lenses 35 and 37 , and the object-side eleventh surface S11 may be convex and the sensor-side twelfth surface S12 may be convex.

The seventh lens 37 is disposed between the sixth and eighth lenses 36 and 38, the object-side thirteenth surface S13 may be convex, and the sensor-side fourteenth surface S14 may be flat. The lens 38 is disposed between the seventh and ninth lenses 37 and 39 , and the object-side fifteenth surface S15 may be convex and the sensor-side sixteenth surface S16 may be concave.

The ninth lens 39 is disposed between the eighth and tenth lenses 39 and 40, the object-side 17th surface S17 may be convex, the sensor-side 18th surface S18 may be concave, and the tenth lens Reference numeral 40 denotes a lens closest to the camera module 300 , and the object-side 19th surface S19 may be convex and the sensor-side 20th surface S20 may be concave. The tenth lens 40 may have a meniscus shape convex in the object direction. The shape of the tenth lens 40 may be a coma correction condition by the first lens 31 . That is, both the first lens 31 and the tenth lens 40 may have a meniscus shape convex in the object direction. The lenses of the first inspection optical unit 230 have a symmetrical shape and arrangement with the lenses of the second inspection optical unit 230 , so the description of the second inspection optical unit 230 will be referred to.

In the second inspection optical unit 230 , looking at the thickness of the center, the third lens 33 , the fifth lens 35 , and the ninth lens 39 have a center thickness of 10 mm or less, for example, 3 mm or less. It may be in the range of 10 mm. The tenth lens 40 has a thickness in the range of 20 mm to 30 mm, and the second lens 32 , the fourth lens 34 , the sixth lens 36 , the seventh lens 37 , and the eighth lens 38 . ) and the thickness of the tenth lens 40 may be greater than or equal to 21 mm, for example, from 21 mm to less than 40 mm, among which the thickness of the second lens 32 may be greater than the thickness of the first lens 31 . The tenth lens 40 may have a thickness greater than that of the first lens 31 , the third lens 33 , the fifth lens 35 , and the ninth lens 29 .

Looking at the radius of curvature, when expressed as an absolute value, the second surface S1 of the first lens 31, the fourth surface S4 of the second lens 32, and the fifth surface (S4) of the third lens 33 ( S5), and the eighth surface S8 of the fourth lens 34 may be 700 mm or more, for example, may be in the range of 700 mm to 1000 mm, and the 14th surface S14 of the seventh lens 37 is It may be the largest plane. The fifteenth surface S15 of the eighth lens 38, the eighteenth surface S18 of the ninth lens 39, and the 19th surface S19 and the twentieth surface S20 of the tenth lens 40 are It may be less than 100 mm, and may range from 30 mm to 100 mm.

Looking at the refractive index, the refractive index Nd of the first, 3, 5, 7, 8, 9, and 10 lenses 31 , 33 , 35 , 37 , 38 , 39 and 40 has a higher refractive index than that of the other lenses. and 1.65 or more, and the refractive index of the second, fourth, and sixth lenses 32, 34, and 36 is a low refractive index, and ranges from 1.3 to 1.6.

Looking at the Abbe number (Vd), the second, fourth, and fourth lenses (32, 34, 36) have an Abbe number of 70 or more higher than that of other lenses, and the first, 3, 5, 7, 9, and 10 lenses (31, 33, 35, 37, 39, 40) may be 50 or less, which is lower than the Abbe's number of the lenses.

As for the lens diameter or half aperture of the second inspection optical unit 230 , the object-side first surface S1 of the first lens 31 is the largest, and the first lens 31 in the sensor direction It gradually becomes smaller up to the tenth lens 40 , and the sensor-side twentieth surface S20 of the tenth lens 40 may be the smallest.

Table 3 is an example of lens data of the second inspection optical unit 230 according to the second embodiment.

lens noodle radius of curvature thickness/thickness refractive index Abbesu hemispherical first lens S1 354.599 16.03 1.94596 17.94 101.87 S2 897.205 38.45 100.93 second lens S3 244.893 30 1.497 81.59 92.55 S4 -768.737 1.314 90.98 third lens S5 -799.509 5 1.84667 23.79 90.24 S6 174.722 0.8 84.73 4th lens S7 140.914 30 1.4586 90.19 85.97 S8 793.503 0.5 85.23 5th lens S9 544.029 5 1.94596 17.94 84.83 S10 156.557 7.561 81.52 6th lens S11 210.048 30 1.4586 90.19 81.03 S12 -430.663 0.3 82.24 7th lens S13 151.791 28.5 1.94596 17.94 82.06 S14 infinity 0.3 80.73 8th lens S15 74.042 25.93 1.72916 54.67 59.69 S16 174.978 5.11 55.36 9th lens S17 261.398 5 1.180811 22.69 52.42 S18 42.452 1.166 36.6 10th lens S19 42.111 24.79 1.883 40.81 36.31 S20 53.862 32.258 27.27 Stop infinity 0.000 2 Image infinity 0.000

In Table 3, the stop-in diaphragm position may be the object-side surface closest to the object-side of the lens optical system 310 , and the lens optical system 310 has an effective focal length of 4 mm.

Table 4 below is data on object distances from infinity to 100 mm and -100 mm at infinity according to the first embodiment, where D0 is a chart position in the second inspection optic, and D2 is in the second inspection optic. It is the effective focal length according to the object distance change, and the MAG value is the image size/object size value.

Config infinity 100 mm -100 mm DO 63.7599 -80.2278 207.7722 D2 4 4.16723 3.84665 MAG 0.03333 0.03484 0.03195

Referring to FIG. 8 , the second inspection optical unit 240 according to the third embodiment includes nine lenses. Accordingly, in the inspection optical system 200 of FIG. 2 according to the third embodiment, the first and second inspection optical units 210 and 240 may be formed of nine lenses. The nine lenses of the first inspection optical unit 210 and the nine lenses of the second inspection optical unit 240 may have a symmetrical shape with respect to the center and may have a symmetrical arrangement. This third embodiment will be described based on the second inspection optical unit 240 , and the first inspection optical unit 210 will refer to the second inspection optical unit 240 , and the relation of Equations 1 to 4 can be satisfied

The second inspection optical unit 240 is an optical system for changing a virtual image of an object located at a finite distance, and may have a telecentric surface on the object side. On the optical axis passing through the center of each lens, the concave or convex structures of the first to ninth lenses are as follows. The first lens 41 may have a meniscus shape in which the object-side first surface S1 is convex and the sensor-side second surface S2 is concave. In the second lens 42 , the object-side third surface S3 may be convex and the sensor-side fourth surface S4 may be concave. In the third lens 43 , the object-side fifth surface S5 may be convex and the sensor-side sixth surface S6 may be concave. The fourth lens 44 may have an object-side seventh surface S7 and a sensor-side eighth surface S8 convex. The fifth lens 45 may have a ninth object-side surface S9 convex and a sensor-side tenth surface S10 convex, and the sixth lens 46 may have an object-side eleventh surface S11 concave. and the sensor-side twelfth surface S12 may be concave. The seventh lens 47 may have an object-side thirteenth surface S13 and a sensor-side fourteenth surface S14 convex, and the eighth lens 48 may have an object-side fifteenth surface S15 . It may be convex and the sensor-side 16th surface S16 may be concave. As for the last lens, the ninth lens 49 may have an object-side 17th surface S17 convex and a sensor-side 18th surface S18 concave.

Looking at the center thickness of the second inspection optical unit 240 , the third lens 43 , the sixth lens 46 , and the eighth lens 48 have a center thickness of 10 mm or less, for example, 3 mm. to 10 mm, and the condition of the eighth lens < the third lens < the sixth lens may be satisfied. The ninth lens 49 has a thickness in the range of 10 mm to 25 mm, and the thickness of the second lens 42 , the fourth lens 44 , and the fifth lens 45 is 26 mm or more, for example, 26 mm to 40 mm. mm, the thickness of the first lens 41, the seventh lens 47, and the ninth lens 49 may be 25 mm or less, for example, in the range of 13 mm to 25 mm. The thickness of the ninth lens 49 may be greater than the thickness of the third lens 43 , the sixth lens 46 , and the eighth lens 48 .

Looking at the radius of curvature, when expressed as an absolute value, the second surface S2 of the first lens 41, the fourth surface S4 of the second lens 42, and the fifth surface (S4) of the third lens 43 ( S5) may be 750 mm or more, for example, may be in the range of 750 mm to 1200 mm, of the 15th surface (S15) and the 16th surface (S16) of the eighth lens 48, and the ninth lens (49). The 17th surface S17 and the 18th surface S18 may be less than 100 mm, and may range from 20 mm to 100 mm.

Looking at the refractive index, the refractive index Nd of the first, 3, 6, 7, 8, and 9 lenses 41, 43, 46, 47, 48, 49 is a high refractive index higher than that of the other lenses and is 1.6 or more, The refractive index of the 2, 4, 5 lenses 42, 44, and 45 is a low refractive index lower than a high refractive index, and may be less than 1.6. Looking at the Abbe's number (Vd), the second and fifth lenses 42 and 45 have 70 or more higher than the other lenses, and the first, 3, 6, 7, 8, and 9 lenses 41, 43, 46, 47, 48, 49) may be 50 or less.

As for the lens diameter or half aperture of the second inspection optical unit 240 , the object-side first surface S1 of the first lens 41 is the largest, and the first lens 41 is directed toward the sensor. The ninth lens 49 gradually decreases, and the sensor-side 18th surface S18 of the ninth lens 49 may be the smallest.

Table 5 is an example of lens data of the second inspection optical unit 240 according to the third embodiment.

lens noodle radius of curvature thickness/thickness refractive index Abbesu hemispherical first lens S1 350.009 23.700 2.001 29.13 146.97 S2 1000.000 85.816 146.51 second lens S3 191.977 34.964 1.45860 90.19 115.19 S4 996.827 1.176 113.91 third lens S5 858.929 6.000 1.84666 23.78 112.71 S6 152.525 22.297 100.03 4th lens S7 374.123 31.698 1.72916 54.67 99.98 S8 -374.123 1.648 99.54 5th lens S9 154.027 35.000 1.45860 90.19 82.96 S10 -525.722 6.315 80.77 6th lens S11 -280.306 7.721 1.76182 26.61 79.69 S12 668.143 47.603 73.84 7th lens S13 208.748 17.263 1.83481 42.72 55.27 S14 -468.085 0.300 53.08 8th lens S15 91.012 4.408 1.74077 27.76 40.93 S16 55.930 0.300 35.55 9th lens S17 44.209 19.328 1.92286 20.88 33.58 S18 40.865 27.911 23.62 Stop infinity 2 Image infinity

Table 6 is data on object distances from infinity to 100 mm and -100 mm from infinity according to the third embodiment, where D0 is the chart position, D2 is the effective focal length according to the change of the object distance, and the MAG value is the image sensor It is a value of size/object size.

Config infinity 100 mm -100 mm DO 5 -297.6727 297.67271 D2 4 4.16668 3.850232 MAG 0.02303 0.02392 0.02223

Referring to FIG. 9 , the inspection optical system according to the fourth embodiment may include a second inspection optical system 250 . When the second inspection optical system 250 of FIG. 9 is applied to FIG. 2 , in the inspection optical system 200 , the first and second inspection optical units 210 and 250 may include 10 lenses. The ten lenses of the first inspection optical unit 210 and the ten lenses of the second inspection optical unit 250 may have a symmetrical shape with respect to the center and may have a symmetrical arrangement. This fourth embodiment will be described based on the second inspection optical unit 250 , and the first inspection optical unit 210 will refer to the second inspection optical unit 250 , and the relationship of Equations 1 to 4 will be can be satisfied

As shown in FIG. 9 , the second inspection optical unit 250 is an optical system for changing a virtual image of an object located at a finite distance, and may have a telecentric surface on the object side. On the optical axis passing through the center of each lens, the concave or convex structures of the first to tenth lenses 51-60 are as follows. The first lens 51 may have an object-side first surface S1 convex and a sensor-side second surface S2 concave. The first lens 51 may have a meniscus shape convex toward the object.

Both the object-side third surface S3 and the sensor-side fourth surface S4 of the second lens 52 may be convex. The second lens 52 may be spaced apart from the first lens 51 by the largest optical axis distance L2 and may be spaced apart from the third lens 53 by the second largest optical axis distance.

The third lens 53 may have a fifth object-side surface S5 concave and a sensor-side sixth surface S6 concave. In the fourth lens 54 , the object-side seventh surface S7 may be convex and the sensor-side eighth surface S8 may be convex. The fifth lens 55 has an object-side ninth surface S9 is convex, and a surface in which the sensor-side tenth surface S10 and the object-side eleventh surface S11 of the fifth lens 55 are joined. The sixth lens 56 may have a concave twelfth surface S12 on the sensor side. The seventh lens 57 may have a thirteenth object-side surface S13 convex and a sensor-side fourteenth surface S14 concave, and the eighth lens 58 may have an object-side fifteenth surface S15 . It may be convex and the sensor-side 16th surface S16 may be concave. The ninth lens 59 may have an object-side 17th surface S17 convex and a sensor-side 18th surface S18 concave, and the tenth lens 60 may have an object-side 19th surface S19 convex. and the sensor-side twentieth surface S20 may be concave. In the fourth embodiment, in the first and second inspection optical units 210 and 250 , the sensor-side tenth surface S10 of the fifth lens 55 and the object-side eleventh surface S11 of the sixth lens 56 are each other It may be provided with a bonded surface.

Looking at the center thickness of the second inspection optical unit 250 , the first lens 51 , the second lens 52 , the fourth lens 54 , the fifth lens 55 , the seventh lens 57 , The thickness of the eighth lens 58 may be 20 mm or more, for example, it may be in the range of 20 mm to 40 mm, among which the second lens 52 , the fourth lens 54 , the fifth lens 55 , and the seventh lens. (57) may be 30 mm or more. The third lens 53 , the sixth lens 56 , and the ninth lens 59 may have a center thickness of 10 mm or less, for example, in the range of 2 mm to 10 mm, and the ninth lens < third lens < sixth The lens condition can be satisfied.

Looking at the radius of curvature, when expressed as an absolute value, the second surface S2 of the first lens 51 , the fifth surface S5 of the third lens 53 , and the thirteenth surface ( S5 ) of the seventh lens 57 ( S13) may be 900 mm or more, for example, may be in the range of 900 mm to 1100 mm, the 14th surface S14 of the seventh lens 57, the 17th surface S17 and the 18th surface of the ninth lens 59 The surface S18 and the 19th surface S19 of the tenth lens 60 may be less than 100 mm, and may be in the range of 30 mm to 100 mm.

As for the lens diameter or half aperture of the second inspection optical unit 250 , the object-side first surface S1 of the first lens 51 is the largest, and the lens diameter or the half aperture of the second inspection optical unit 250 is the largest in the sensor direction from the first lens 51 . It gradually becomes smaller up to the tenth lens 60, and the sensor-side twentieth surface S20 of the tenth lens 60 may be the smallest.

Table 7 shows lens data of the second inspection optical unit 250 according to the fourth embodiment.

lens noodle radius of curvature thickness/thickness refractive index Abbesu hemispherical first lens S1 384.933 25.000 2.00069 25.46 137.34 S2 1000.000 90.000 135.71 second lens S3 349.964 35.000 1.45860 90.19 113.01 S4 -743.475 27.921 110.92 third lens S5 -1000.000 6.000 1.84666 23.78 94.94 S6 166.323 3.515 87.87 4th lens S7 181.618 35.000 1.49700 81.61 88.05 S8 -675.981 0.300 87.51 5th lens S9 1998.29 35.000 1.45860 90.19 82.85 6th lens S10 (S11) -296.171 8.995 1.75520 27.53 81.3 S12 573.272 4.249 77.01 7th lens S13 100.068 34.000 1.45860 90.19 71.43 S14 932.835 0.300 68.7 8th lens S15 77.860 25.000 2.00069 25.46 55.65 S16 119.320 5.599 46.73 9th lens S17 210.403 4.000 1.59270 35.45 45.26 S18 41.195 4.299 33.04 10th lens S19 45.241 17.204 2.00069 25.46 32.34 S20 53.419 27.767 24.94 Stop infinity 2 Image infinity

Table 8 is data on object distances from infinity to 100 mm and -100 mm at infinity according to the third embodiment, where D0 is the chart position, D2 is the effective focal length according to the change of the object distance, and the MAG value is the image Value of sensor size/object size.

Config infinity 100 mm -10 mm DO 5 -248.608193 258.6082 D2 4 4.16704 3.84162 MAG 0.025322 0.02601 0.02467

In the inspection optical system according to the first to fourth embodiments (example), data according to each embodiment of Equation (ep) 1-4 and L2, TL, Yobj, D1, L0, Omax, F data can be obtained as shown in Table 9 below.

Example 1 Example 2 Example 3 Example 4 Formula 1 0.1503415 0.3201693 0.2483569 0.2490433 Formula 2 0.4908216 0.4931358 0.4762877 0.4805592 Equation 3 0.2493046 0.0556816 0.0144703 0.0138357 Formula 4 0.8306384 0.6093527 0.575582 0.6316508 L2 38.45 115 85.816 90 T.L. 255.751 359.185 345.535 361.383 Yobj 100 136.5 140 132 D1 203.74 276.8 293.94 274.68 L0 63.7599 20 5 5 Omax 99.676613 99.99808 99.992321 99.785441 F 120 164.10543 173.72385 157.97563

The inspection optical system for a camera module according to an embodiment of the present invention can measure a short distance and a long distance at the same time without using a collimator lens. In addition, MTF measurement is possible through the electronic chart that moves the fixed inspection optical system to the optical axis, so it is possible to verify whether the lens optical system in the camera module is tilted on the image sensor, and to verify the epoxy shrinkage problem due to lens adhesion. .

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

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

100: electronic chart unit
110: light source
120: electronic chart
200: inspection optical system
210,220: inspection optics
300: camera module
310: lens optical system
320: image sensor

Claims (10)

a first inspection optical unit having a plurality of lenses aligned with an optical axis from the object side to the sensor side; and
It is disposed between the first inspection optical unit and the camera module to be tested and includes a second inspection optical unit having a plurality of lenses,
The lenses of the first inspection optical unit and the second inspection optical unit have a shape and arrangement symmetrical to each other at a center between the first inspection optical unit and the second inspection optical unit,
Each of the first and second inspection optics is a telecentric optical system, the inspection optical system of the camera module. The method of claim 1,
and each of the first and second inspection optics has 9 or 10 lenses. The method of claim 1,
The diameter of the lenses of the first inspection optics gradually increases from the object side to the sensor side,
The diameter of the lenses of the second inspection optical unit gradually decreases from the object side to the sensor side. The method of claim 1,
In the second inspection optical unit, the lens closest to the object side or the first inspection optical unit has a meniscus shape convex toward the object side. 5. The method of claim 4,
In the second inspection optical unit, the lens furthest from the sensor side or the first inspection optical unit has a meniscus shape convex toward the object side. 6. The method according to any one of claims 1 to 5,
The second inspection optical unit satisfies Equation 1 below,
[Formula 1]
0.1 ≤ ｜L2/TL｜ ≤0.5
L2 is the optical axis distance between the sensor-side second surface of the first lens closest to the object side and the object-side third surface of the second lens adjacent thereto,
wherein TL is an optical axis distance from the object-side first surface of the first lens to the sensor-side surface of the lens closest to the camera module. 6. The method according to any one of claims 1 to 5,
The second inspection optical unit satisfies the following Equation 2,
[Equation 2]
0.4 ≤ ｜Yobj/D1｜ ≤ 0.5
wherein D1 is the diameter of the first lens closest to the object side, and Yobj is the maximum image height with respect to the object. 6. The method according to any one of claims 1 to 5,
The second inspection optical unit satisfies the following Equation 3,
[Equation 3]
0.0 ≤ ｜L0/TL｜ ≤0.3
When the virtual image distance is infinity, L0 is the distance from the center to the first object-side surface of the first lens, and TL is the total optical axis distance of the second inspection optical unit. 6. The method according to any one of claims 1 to 5,
An angle between the chief ray and the optical axis at the maximum image height of the object in the second inspection optical unit is 1 degree or less. an electronic chart unit having a light source and an electronic chart;
a camera module having a lens optical system and an image sensor, and having no actuator therein; and
and an inspection optical system disposed between the electronic chart unit and the camera module and condensing the light beam passing through the electronic chart on the camera module,
The inspection optical system is an inspection optical system according to any one of claims 1 to 5, a camera module inspection apparatus.

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