Contact type image sensor lens

Abstract

The invention discloses a contact type image sensor lens which comprises a lens array formed by combining a plurality of cylindrical lenses, and the cylindrical lenses enable a scanned object to form an upright image at the magnification of 1: 1; the cylindrical lens comprises a first convex curved surface and a second convex curved surface which are distributed along the light passing axis. The first convex curved surface and the second convex curved surface are located at the two opposite ends of the cylindrical lens. The lenticular lens is made of a uniform material. The technical problem that in the prior art, the cost is high due to the fact that a rod lens made of materials with gradually-changed refractive indexes is adopted to manufacture a contact type image sensor is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical technology, and in particular to a contact image sensor lens. BACKGROUND

[0002] A contact image sensor (CIS) integrates a rod lens, an LED array light source, a photosensitive element array, and a signal amplification circuit. The light emitted by the LED array light source is reflected by a scanned object, and then is projected and focused on the photosensitive element array by the rod lens. The photosensitive element array converts the light signal into an electrical signal, and the complete image of the scanned object is directly formed after the rear-end processing. Due to the overall integration of the CIS, the volume can be effectively controlled, and the device portability and overall integration are obviously advantageous. The rod lens is used to realize 1:1 imaging of the object and the photosensitive element, and the object is restored with high quality. The CIS is first used in devices such as fax machines and scanners. At present, it has a huge application space in the optical detection of financial equipment (such as a currency detector), medical equipment, and industrial detection (such as a film, a semiconductor, and a lithium battery) equipment.

[0003] The rod lens in the prior art is usually a lens made of a material with a gradual refrective index along the radial direction. However, the rod lens designed by using the material with a gradual refrective index has a high cost for manufacturing the contact image sensor. SUMMARY

[0004] The embodiment of the present application provides a contact image sensor lens to solve the technical problem of high cost of the contact image sensor manufactured by using the rod lens designed by the material with a gradual refrective index in the prior art.

[0005] The embodiment of the present application provides a contact image sensor lens, which comprises a lens array composed of a plurality of rod lenses, and the rod lens makes a scanned object form a positive image with a magnification of 1:1.

[0006] The rod lens comprises a first convex surface and a second convex surface distributed along an optical axis, and the first convex surface and the second convex surface are located at opposite ends of the rod lens.

[0007] The rod lens is made of a uniform material.

[0008] Optionally, the rod lens comprises a first plano-convex lens and a second plano-convex lens.

[0009] The first plano-convex lens comprises the first convex surface and a first plane, and the second plano-convex lens comprises the second convex surface and a second plane.

[0010] The first convex surface, the first plane, the second plane and the second convex surface are arranged in sequence along the direction of the light passing axis.

[0011] Optionally, the first plane and the second plane are arranged in a spaced manner.

[0012] Alternatively, the first plano-convex lens and the second plano-convex lens are glued by optical glue.

[0013] Optionally, the cylindrical lens further comprises a central flat lens, which is located between the first plano-convex lens and the second plano-convex lens.

[0014] Optionally, the cylindrical lens comprises a double-convex rod lens, which comprises the first convex surface and the second convex surface.

[0015] Optionally, a first array lens plate and a second array lens plate are arranged along the light passing axis.

[0016] The first array lens plate comprises a plurality of the first convex surfaces, and the second array lens plate comprises a plurality of the second convex surfaces. The first convex surfaces and the second convex surfaces arranged along the light passing axis belong to the same cylindrical lens.

[0017] Optionally, a central plate is further included, which is located between the first array lens plate and the second array lens plate, and a light passing surface of the central plate comprises a plane.

[0018] Optionally, the first array lens plate, the central plate and the second array lens plate are glued by optical glue.

[0019] Alternatively, the first array lens plate and the central plate are arranged in a spaced manner, and the central plate and the second array lens plate are arranged in a spaced manner.

[0020] Optionally, the first array lens plate and the second array lens plate are arranged in a spaced manner.

[0021] Alternatively, the first array lens plate and the second array lens plate are glued by optical glue.

[0022] Optionally, a third array lens plate is included,

[0023] A first side of the third array lens plate comprises a plurality of the first convex surfaces, and a second side of the third array lens plate comprises a plurality of the second convex surfaces.

[0024] The first convex surfaces and the second convex surfaces arranged along the light passing axis belong to the same cylindrical lens.

[0025] The embodiment of the present application provides a contact image sensor lens, which comprises a lens array combined by a plurality of columnar lenses, the columnar lens forms a positive image of a scanned object with a magnification of 1:1; the columnar lens comprises a first convex surface and a second convex surface distributed along an optical axis, and the first convex surface and the second convex surface are located at opposite ends of the columnar lens; and the columnar lens is made of a uniform material. The first convex surface and the second convex surface are located at opposite ends of the columnar lens, so that the columnar lens can also form a positive image of a scanned object with a magnification of 1:1, the columnar lens can be made of a uniform material, and the cost of manufacturing the contact image sensor can be saved. The technical problem of high cost of manufacturing the contact image sensor by using the rod lens designed by the refractive index gradient material in the prior art is solved.

[0026] It should be understood that the content described in this part is not intended to identify key or important features of the embodiments of the present application, nor is it used to limit the scope of the present application. Other features of the present application will become apparent through the following description. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a structural schematic diagram of a lens array of a related technology provided by the embodiment of the present application;

[0028] Figure 2 is a structural schematic diagram of a columnar lens provided by the embodiment of the present application;

[0029] Figure 3 is a structural schematic diagram of another columnar lens provided by the embodiment of the present application;

[0030] Figure 4 is a structural schematic diagram of another columnar lens provided by the embodiment of the present application;

[0031] Figure 5 is a structural schematic diagram of another columnar lens provided by the embodiment of the present application;

[0032] Figure 6 is a structural schematic diagram of a contact image sensor lens provided by the embodiment of the present application;

[0033] Figure 7 is a structural schematic diagram of another contact image sensor lens provided by the embodiment of the present application;

[0034] Figure 8 is a structural schematic diagram of another contact image sensor lens provided by the embodiment of the present application;

[0035] Figure 9 is a structural schematic diagram of another contact image sensor lens provided by the embodiment of the present application;

[0036] Figure 10 Schematic diagram of the structure of another contact image sensor lens provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0037] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0038] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0039] Figure 1 This is a schematic diagram of the structure of a lens array of related technology provided by an embodiment of the present invention, with reference to Figure 1 In the related art, the cylindrical lenses 1 are combined to form the lens array. The cylindrical lenses 1 of the related art can be arranged in a one-dimensional linear array pattern, or can be arranged in a linear array pattern. Figure 1 The two-dimensional array pattern shown (usually two rows) allows the lens array to fill the space more tightly. The cylindrical lens 1 is generally designed to image the scanned object as a positive image with a magnification ratio of approximately 1:1. However, the cylindrical lens 1 in the related art is generally made of a material with a radially gradient refractive index. The cost of manufacturing a contact image sensor using a rod lens designed with a gradient refractive index material is relatively high. To reduce the cost of manufacturing a contact image sensor, an embodiment of the present invention provides a contact image sensor lens, as follows:

[0040] Figure 2 This is a schematic diagram of the structure of a cylindrical lens provided by an embodiment of the present invention. The embodiment of the present invention provides a contact image sensor lens, including a lens array composed of a plurality of cylindrical lenses 1. The cylindrical lenses 1 form an erect image of the scanned object with a magnification ratio of 1:1. Figure 2The cylindrical lens 1 comprises a first convex surface S11 and a second convex surface S21 distributed along the light passing axis, and the first convex surface S11 and the second convex surface S21 are located at opposite ends of the cylindrical lens 1.

[0041] The contact type image sensor lens is actually a macro lens, that is, the distance Li (also referred to as working distance WD) between the scanned object and the front surface of the lens is very small, for example, 1 mm. According to the requirements of the specific use of the device, for example, the resolution range is 50-1200 dpi, and the width range is 18 mm-1960 mm, and the working distance WD can be increased to 30 mm.

[0042] The cylindrical lens 1 in the embodiment of the application realizes the CIS function through a conventional curved lens design. In order to realize that the cylindrical lens 1 forms a positive image of the scanned object with a magnification of 1:1, the cylindrical lens 1 can be designed as a lens group composed of two separate plano-convex lenses, or as a double convex rod lens formed by gluing two plano-convex lenses, or as a whole double convex rod lens.

[0043] It should be noted that the first convex surface S11 and the second convex surface S21 are located at opposite ends of the cylindrical lens 1, and the cylindrical lens 1 can also realize that the scanned object is imaged with a magnification of 1:1. The cylindrical lens 1 can be made of uniform material, which can save the cost of manufacturing the contact image sensor. The technical problem of high cost of manufacturing the contact image sensor by using the rod lens designed by the refractive index gradient material in the prior art is solved.

[0044] Optionally, on the basis of the above embodiment, continuing to refer to Figure 2 The cylindrical lens 1 comprises a first plano-convex lens 11 and a second plano-convex lens 12; the first plano-convex lens 11 comprises a first convex surface S11 and a first plane S12, and the second plano-convex lens 12 comprises a second convex surface S21 and a second plane S22; along the direction of the light passing axis, the first convex surface S11, the first plane S12, the second plane S22 and the second convex surface S21 are sequentially arranged.

[0045] Specifically, the first plano-convex lens 11 and the second plano-convex lens 12 in the embodiment have the same refractive index n and curvature radius r. The thickness d1 of the first plano-convex lens 11 is equal to the thickness d2 of the second plano-convex lens 12, the air gap length between the first plane S12 and the second plane S22 is D, the first plano-convex lens 11 and the second plano-convex lens 12 are arranged as a 2f+2f+2f+2f system, the scanned object is located at a position of Li=2f in front of the first plano-convex lens 11, and a positive image with a magnification of 1:1 is obtained at a position of Lo=2f behind the second plano-convex lens 12. For example, taking the refractive index n=1.9, the spherical radius r=1.1 mm, the thickness d1=d2=1.0 mm, and the air gap D=3.85 mm, the lens focal length f=1.22 mm can be obtained. At this time, the image distance Lo=the object distance Li=2f=2.44 mm, the total length of the optical system Z=5.85 mm, and the total length of the optical path Tc=10.73 mm. It should be noted that, Figure 2 In the formula, a is the distance between the object-side principal section and the image-side principal section of the first plano-convex lens 11 or the second plano-convex lens 12.

[0046] It should be noted that in the embodiment of the present application, the imaging light path is arranged according to 2f+2f+2f+2f, the position of the object is 2f away from the left end of the first plano-convex lens 11, and the position of the image is 2f away from the right end of the second plano-convex lens 12. However, this is only a preferred embodiment for easy understanding. The inverted real image in the middle of the first plano-convex lens 11 and the second plano-convex lens 12 is at the same height as the object. In fact, the position of the object can be 2f away from the left end of the first plano-convex lens 11, farther or closer. At this time, the air gap length D in the middle of the first plano-convex lens 11 and the second plano-convex lens 12 is adjusted accordingly, so that the 1:1 positive image on the image side can be realized. However, at this time, the inverted real image in the middle of the first plano-convex lens 11 and the second plano-convex lens 12 is not at the same height as the object.

[0047] Figure 3 is another structure diagram of a cylindrical lens provided by the embodiment of the present application. Optionally, on the basis of the above embodiment, the first plane S12 and the second plane S22 are arranged at intervals; or, on the basis of the above embodiment, the first plano-convex lens 11 and the second plano-convex lens 12 are glued by optical glue. Figure 2 Figure 3

[0048] It can be understood that the first plano-convex lens 11 and the second plano-convex lens 12 are arranged as a 2f+2f+2f+2f system. Figure 2 ​​The air gap D length between the first plane S12 and the second plane S22 in the first convex lens 11 and the second convex lens 12 is designed as 0, that is, the first convex lens 11 and the second convex lens 12 are glued by optical glue, and a double convex rod lens can be obtained. For example, the refractive index n is 1.9, the spherical radius r is 1.1 mm, and the total length Z of the single lens is 9.28 mm. At this time, the image distance Lo is 2.44 mm, the object distance Li is 2.44 mm, and the total length Tc of the optical path is 14.17 mm.

[0049] In the above embodiment, the first convex lens 11 and the second convex lens 12 are glued by optical glue, which can further reduce the processing difficulty on the basis of saving the cost of manufacturing the contact image sensor.

[0050] Optionally, in the above embodiment, referring to Figure 3 , the optical glue surface position is arranged upwardly spaced from the central axis of the columnar lens 1.

[0051] It should be noted that the optical glue surface position is arranged upwardly spaced from the central axis of the columnar lens 1, that is, the gluing position of the first convex lens 11 and the second convex lens 12 is not located at the center of symmetry of the columnar lens 1, that is, the lengths of the first convex lens 11 and the second convex lens 12 are different, for example, d1=3.5 mm and d2=5.78 mm.

[0052] It can be understood that since the central axis of the columnar lens 1 has good focusing effect upwardly, the light intensity is strong, and any slight defect of the interface may affect the imaging quality. In the embodiment of the present application, the optical glue surface position is arranged upwardly spaced from the central axis of the columnar lens 1, which can ensure good imaging quality on the basis of saving the cost of manufacturing the contact image sensor.

[0053] Figure 4 is another structure diagram of a columnar lens provided by the embodiment of the present application, Figure 5 is another structure diagram of a columnar lens provided by the embodiment of the present application, and optionally, in the above embodiment, referring to Figure 4 and Figure 5 , the columnar lens 1 includes a double convex rod lens, and the double convex rod lens includes a first convex surface S11 and a second convex surface S21.

[0054] It can be understood that the double convex rod lens in the embodiment of the present application can be designed as Figure 4 the whole double convex rod lens, or can be designed as the structure shown in Figure 5 . Referring to Figure 5The cylindrical lens 1 further comprises a central flat lens 13 between the first plano-convex lens 11 and the second plano-convex lens 12. The first plano-convex lens 11 is cemented with the central flat lens 13, and the central flat lens 13 is cemented with the second plano-convex lens 12. The first plano-convex lens 11, the central flat lens 13 and the second plano-convex lens 12 form a cemented piece, which is divided into three sections with the refractive index n = 1.9, the spherical radius r = 1.1 mm and the total length of single lens Z = 9.28 mm, for example, d1 = d2 = 1.0 mm, and the thickness d3 of the central flat lens 13 = 7.28 mm.

[0055] Figure 6 is a structural schematic diagram of a contact image sensor lens provided by an embodiment of the present application, Figure 7 is a structural schematic diagram of another contact image sensor lens provided by an embodiment of the present application. Optionally, on the basis of the above embodiment, reference is made to Figure 6 and Figure 7 The contact image sensor lens comprises a first array lens plate A11 and a second array lens plate A12 distributed along an optical axis. The first array lens plate A11 comprises a plurality of first convex curved surfaces S11, and the second array lens plate A12 comprises a plurality of second convex curved surfaces S21. The first convex curved surfaces S11 and the second convex curved surfaces S21 distributed along the optical axis belong to the same cylindrical lens 1.

[0056] It should be noted that the rod lens designed by the refractive index gradient material in the prior art can only form an array by accurate arrangement and fixation of one by one. Since the cylindrical lens 1 in the embodiment of the present application is manufactured by uniform material, the first array lens plate A11 and the second array lens plate A12 can be manufactured by a molding process. By accurately controlling the mold surface type and the molding process, the first array lens plate A11 and the second array lens plate A12 can be manufactured in large quantities and at low cost.

[0057] Since the first array lens plate A11 in the embodiment comprises a plurality of first convex curved surfaces S11, the second array lens plate A12 comprises a plurality of second convex curved surfaces S21, and the first convex curved surfaces S11 and the second convex curved surfaces S21 distributed along the optical axis belong to the same cylindrical lens 1, the first array lens plate A11 and the second array lens plate A12 can be manufactured by a molding manufacturing process combined with a cementing process, which can ensure the consistency of the size and shape of each cylindrical lens 1 and the accuracy of the position, greatly improve the assembly efficiency, and greatly reduce the cost of the contact image sensor lens.

[0058] Optionally, on the basis of the above embodiment, reference is made to Figure 6 and Figure 7The contact image sensor lens further comprises a central plate A13 located between the first array lens plate A11 and the second array lens plate A12, and a light passing surface of the central plate A13 comprises a plane.

[0059] Optionally, based on the above-mentioned embodiments, further referring to Figure 6 , the first array lens plate A11, the central plate A13 and the second array lens plate A12 are glued by optical glue; or, based on the above-mentioned embodiments, further referring to Figure 7 , the first array lens plate A11 and the central plate A13 are arranged in a spaced manner, and the central plate A13 and the second array lens plate A12 are arranged in a spaced manner.

[0060] It can be understood that the first array lens plate A11, the central plate A13 and the second array lens plate A12 in the embodiments of the present application can be glued by optical glue, and the first array lens plate A11, the central plate A13 and the second array lens plate A12 can also be designed as three discrete pieces without gluing, and there is an air gap in the middle. Whether to glue is determined according to the use requirement.

[0061] It should be noted that the central plate A13 is used to adjust the total length of the entire cylindrical lens 1, and since the refractive index of the central plate A13 is greater than the refractive index of air, for example, the refractive index of the central plate is 1.5, which is equivalent to lengthening the optical path, and the optical path length of the central plate A13 is longer than that of the air layer with the same thickness, which can facilitate position adjustment.

[0062] Figure 8 is another structure schematic view of a contact image sensor lens provided by the embodiments of the present application, Figure 9 is another structure schematic view of a contact image sensor lens provided by the embodiments of the present application, and optionally, based on the above-mentioned embodiments, referring to Figure 8 , the first array lens plate A11 and the second array lens plate A12 are arranged in a spaced manner; or, based on the above-mentioned embodiments, referring to Figure 9 , the first array lens plate A11 and the second array lens plate A12 are glued by optical glue.

[0063] It can be understood that when the first plano-convex lens 11 and the second plano-convex lens 12 in Figure 2 are used for mold pressing to manufacture an integral lens, the manufactured first array lens plate A11 and the second array lens plate A12 are arranged in a spaced manner as shown in Figure 8 , that is, the structure of the contact image sensor lens is two large pieces in space. Figure 3When the first plano-convex lens 11 and the second plano-convex lens 12 are molded to manufacture the integral lens, the first array lens plate A11 and the second array lens plate A12 are manufactured as shown in FIG. Figure 9 As shown, the contact image sensor lens is bonded together by optical bonding, that is, two large pieces are bonded together.

[0064] It should be noted that for molding production, manufacturing aspheric molds does not increase costs, so Figures 6-9 In the corresponding embodiment, the first array lens plate A11 and the second array lens plate A12 can both be designed as aspherical lens arrays, which have better optical imaging performance than spherical lens arrays and better imaging performance than the prior art refractive index gradient rod mirror.

[0065] Figure 10 This is a schematic structural diagram of another contact image sensor lens provided by an embodiment of the present invention. Optionally, based on the above embodiment, reference is made to Figure 10 The contact image sensor lens includes a third array lens plate A14, the first side of the third array lens plate A14 includes a plurality of first convex surfaces S11, and the second side of the third array lens plate A14 includes a plurality of second convex surfaces S21; the first convex surfaces S11 and the second convex surfaces S21 distributed along the light axis belong to the same cylindrical lens 1.

[0066] It is understandable that when Figure 4 When the entire double convex rod mirror is molded to manufacture an integral lens, the third array lens plate A14 can be manufactured, that is, the integral lens with convex surfaces at both ends can be directly molded and molded at one time to directly obtain the contact image sensor lens.

[0067] In summary, the embodiment of the present application sets the first convex surface S11 and the second convex surface S21 at opposite ends of the columnar lens 1, and can also achieve the columnar lens 1 to form a positive image of the scanned object with a magnification of 1:1. The columnar lens 1 is made of uniform material, which can save the cost of manufacturing the contact image sensor. The technical problem of high cost of manufacturing the contact image sensor by the rod lens designed by the refractive index gradient material in the prior art is solved. In addition, the first plano-convex lens 11 and the second plano-convex lens 12 are glued by optical glue, which can further reduce the processing difficulty on the basis of saving the cost of manufacturing the contact image sensor. The optical glue surface position is spaced upward from the central axis of the columnar lens 1, which can ensure good imaging quality on the basis of saving the cost of manufacturing the contact image sensor. Since the first array lens plate A11 includes a plurality of first convex surfaces S11, the second array lens plate A12 includes a plurality of second convex surfaces S21, and the first convex surfaces S11 and the second convex surfaces S21 distributed along the optical axis belong to the same columnar lens 1, the first array lens plate A11 and the second array lens plate A12 can be manufactured by a mold pressing manufacturing process combined with a gluing process, which can ensure the consistency of the size and shape of each columnar lens 1 and the accuracy of the position, greatly improve the assembly efficiency, and greatly reduce the cost of the contact image sensor lens. The first array lens plate A11 and the second array lens plate A12 are designed as aspherical lens arrays, and the optical imaging performance is better than that of the spherical lens array, and the imaging performance is better than that of the refractive index gradient rod lens in the prior art.

[0068] It should be noted that the above only describes the preferred embodiments of the present application and the technical principles applied. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and those skilled in the art can make various obvious changes, re-adjustments, mutual combinations and substitutions without departing from the scope of the present application. Therefore, although the present application has been described in detail through the above embodiments, the present application is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the appended claims.

Claims

1. A contact image sensor lens, characterized in that: The lens array comprises a plurality of cylindrical lenses, wherein the cylindrical lenses form an erect image of the scanned object with a magnification ratio of 1:1; The cylindrical lens comprises a first convex surface and a second convex surface distributed along the light transmission axis, wherein the first convex surface and the second convex surface are located at opposite ends of the cylindrical lens; The cylindrical lens is made of a uniform material.

2. The contact image sensor lens according to claim 1, wherein The cylindrical lens includes a first plano-convex lens and a second plano-convex lens; The first plano-convex lens includes the first convex curved surface and a first plane, and the second plano-convex lens includes the second convex curved surface and a second plane; Along the direction of the light-passing axis, the first convex curved surface, the first plane, the second plane and the second convex curved surface are arranged in sequence.

3. The contact image sensor lens according to claim 2, wherein: The first plane and the second plane are spaced apart from each other; Alternatively, the first plano-convex lens and the second plano-convex lens are bonded together by optical bonding.

4. The contact image sensor lens according to claim 2, wherein: The cylindrical lens further includes a central plano lens, and the central plano lens is located between the first plano-convex lens and the second plano-convex lens.

5. The contact image sensor lens according to claim 1, wherein The cylindrical lens includes a biconvex rod lens, and the biconvex rod lens includes the first convex curved surface and the second convex curved surface.

6. The contact image sensor lens according to claim 1, wherein The invention comprises a first array lens plate and a second array lens plate distributed along the light-passing axis; The first array lens plate includes a plurality of the first convex curved surfaces, the second array lens plate includes a plurality of the second convex curved surfaces, and the first convex curved surfaces and the second convex curved surfaces distributed along the light transmission axis belong to the same cylindrical lens.

7. The contact image sensor lens according to claim 6, wherein: The system further comprises a central plate, which is located between the first array lens plate and the second array lens plate, and a light-transmitting surface of the central plate comprises a plane.

8. The contact image sensor lens according to claim 7, wherein: The first array lens plate, the central plate, and the second array lens plate are bonded together by optical glue; Alternatively, the first array lens plate is spaced apart from the central plate, and the central plate is spaced apart from the second array lens plate.

9. The contact image sensor lens according to claim 6, wherein: The first array lens plate and the second array lens plate are spaced apart from each other; Alternatively, the first array lens plate and the second array lens plate are bonded together by optical adhesive.

10. The contact image sensor lens according to claim 1, wherein comprising a third array lens plate, wherein a first side of the third array lens plate comprises a plurality of the first convex curved surfaces, and a second side of the third array lens plate comprises a plurality of the second convex curved surfaces; The first convex surface and the second convex surface distributed along the light-passing axis belong to the same cylindrical lens.

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