Double-view double-working-distance telecentric lens
By designing a dual-field-of-view, dual-working-distance telecentric lens, and utilizing a combination of a front optical group, a beam splitter prism, and two rear optical groups, the problem of insufficient detection by machine vision lenses in rapidly changing detection environments is solved, achieving a detection effect with high comprehensiveness and high accuracy.
Patent Information
- Application Number
- CN202520157733.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-22
- Publication Date
- 2026-01-06
- Estimated Expiration
- 2035-01-22
AI Technical Summary
Existing machine vision lenses are insufficient to meet the stringent requirements of industrial production when facing rapidly changing inspection environments, resulting in inadequate inspection comprehensiveness and accuracy.
Design a dual-field-of-view, dual-working-distance telecentric lens that uses a combination of a front optical group, a beam splitter prism, and two rear optical groups to achieve light distribution and imaging, suitable for object detection at different distances.
It improves the comprehensiveness and accuracy of detection, can adapt to changing detection environments, and meets the needs of different detection scenarios.
Smart Images
Figure CN223770461U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of optical equipment, and in particular to a dual-field-of-view, dual-working-distance telecentric lens. Background Technology
[0002] In industrial production, it is necessary to conduct timely inspections of the production process and the products produced to ensure the stable operation of the industrial production process and that the industrial products meet the requirements. In the existing technology, machine vision lenses are used for inspection. The machine vision lenses acquire images, and then the images are analyzed to facilitate the inspection of the industrial production process and the products produced.
[0003] However, in actual production processes, the inspection environment changes rapidly, and existing machine vision lenses often fall short in the face of such rapidly changing environments, making it difficult to meet the stringent requirements of industrial production.
[0004] Therefore, existing technologies still need to be improved and developed. Utility Model Content
[0005] In view of the shortcomings of the prior art, the purpose of this application is to provide a dual-field-of-view, dual-working-distance telecentric lens for detection in changing detection environments, applicable to different detection scenarios, thereby improving the comprehensiveness and accuracy of detection.
[0006] The technical solution adopted by this application to solve the technical problem is as follows: a dual-field-of-view, dual-working-distance telecentric lens, comprising:
[0007] A front optical group, which is used to align the object being photographed and allow light to enter;
[0008] The beam splitter has a first light-incident end, a first light-outcident end, and a second light-outcident end. The first light-incident end and the first light-outcident end are located on the same straight line, and the second light-outcident end is perpendicular to the first light-outcident end. The first light-incident end is disposed on the light-outcident side of the front optical group.
[0009] The first rear optical group is disposed on the light-emitting side of the first light-emitting end;
[0010] The second rear optical group is disposed on the light-emitting side of the second light-emitting end.
[0011] Furthermore, the front optical group is provided with a first lens, a second lens, a third lens and a fourth lens along the light incident direction, and the beam splitter is located on the side of the fourth lens away from the light incident port.
[0012] Furthermore, the first and second lenses are biconvex lenses, and the third and fourth lenses are biconcave lenses.
[0013] Furthermore, the first lens has a front surface radius of curvature of 200±0.2mm, a rear surface radius of curvature of -550±2mm, a refractive index of 1.6, a dispersion coefficient of 58, an effective aperture of 58±1mm, and a center thickness of 15±0.5mm.
[0014] The second lens has a front surface radius of curvature of 49±0.2mm, a rear surface radius of curvature of -180±0.2mm, a refractive index of 1.49, a dispersion coefficient of 81.6, an effective aperture of 30±1mm, and a center thickness of 17±0.5mm.
[0015] The third lens has a front surface curvature radius of -170.2±0.2mm, a rear surface curvature radius of -222.8±0.2mm, a refractive index of 1.75, a dispersion coefficient of 45, an effective aperture of 27±1mm, and a center thickness of 7±0.5mm.
[0016] The fourth lens has a front surface curvature radius of -122.6±0.2mm, a rear surface curvature radius of 55±0.2mm, a refractive index of 1.62, a dispersion coefficient of 33, an effective aperture of 15±1mm, and a center thickness of 3±0.5mm.
[0017] The beam splitter is a cubic prism with a thickness of 40 mm.
[0018] Furthermore, the first rear optical group is provided with a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, and an eleventh lens in sequence along the direction of light incidence, wherein the fifth lens is located on the side of the beam splitter away from the fourth lens.
[0019] Furthermore, the fifth, sixth, ninth, and eleventh lenses are biconvex lenses, the seventh and eighth lenses are biconcave lenses, the tenth lens is a plano-convex lens, and the eighth and ninth lenses form a set of cemented doublet lenses;
[0020] The fifth lens has a front surface curvature radius of 333.5±0.2mm, a rear surface curvature radius of -111.6±0.2mm, a refractive index of 1.76, a dispersion coefficient of 28, an effective aperture of 7.5±1mm, and a center thickness of 4.2±0.5mm.
[0021] The sixth lens has a front surface curvature radius of 34.2±0.2mm, a rear surface curvature radius of -255.4±0.2mm, a refractive index of 1.51, a dispersion coefficient of 64, an effective aperture of 7.5±1mm, and a center thickness of 6±0.5mm.
[0022] The seventh lens has a front surface curvature radius of -30±0.2mm, a rear surface curvature radius of -44±0.2mm, a refractive index of 1.62, a dispersion coefficient of 36, an effective aperture of 11±1mm, and a center thickness of 3±0.5mm.
[0023] The eighth lens has a front surface curvature radius of -33±0.2mm, a rear surface curvature radius of 177±0.2mm, a refractive index of 1.73, a dispersion coefficient of 25, an effective aperture of 16.5±1mm, and a center thickness of 7±0.5mm.
[0024] The ninth lens has a front surface curvature radius of 177±0.2mm, a rear surface curvature radius of -40.2±0.2mm, a refractive index of 1.6, a dispersion coefficient of 58, an effective aperture of 16.5±1mm, and a center thickness of 11±0.5mm.
[0025] The tenth lens has a flat front surface, a rear surface radius of curvature of -66.3±0.2mm, a refractive index of 1.67, a dispersion coefficient of 47, an effective aperture of 19±1mm, and a center thickness of 8±0.5mm.
[0026] The eleventh lens has a front surface curvature radius of 77±0.2mm, a rear surface curvature radius of -155±0.2mm, a refractive index of 1.67, a dispersion coefficient of 47, an effective aperture of 21±1mm, and a center thickness of 12±0.5mm.
[0027] Furthermore, the second rear optical group is provided with a twelfth, thirteenth, fourteenth, fifteenth, sixteenth, seventeenth and eighteenth lens sequentially along the direction of light incidence, with the twelfth lens located on the side of the beam splitter.
[0028] Furthermore, the twelfth, thirteenth, sixteenth, seventeenth, and eighteenth lenses are biconvex lenses, and the fourteenth and fifteenth lenses are also described.
[0029] The twelfth lens has a front surface curvature radius of 333.5±0.2mm, a rear surface curvature radius of -111.6±0.2mm, a refractive index of 1.76, a dispersion coefficient of 28, and an effective aperture of 7.5±1mm.
[0030] The thirteenth lens has an anterior surface curvature radius of 12.5±0.2mm, a posterior surface curvature radius of -44.6±0.2mm, a refractive index of 1.65, a dispersion coefficient of 44, an effective aperture of 4±1mm, and a center thickness of 2.5±0.5mm.
[0031] The fourteenth lens has an anterior surface curvature radius of -13±0.2mm, a posterior surface curvature radius of 12.4±0.2mm, a refractive index of 1.62, a dispersion coefficient of 36, an effective aperture of 5.5±1mm, and a center thickness of 2±0.5mm.
[0032] The fifteenth lens has an anterior surface curvature radius of -8.5±0.2mm, a posterior surface curvature radius of 24±0.2mm, a refractive index of 1.75, a dispersion coefficient of 25, an effective aperture of 6±1mm, and a center thickness of 2±0.5mm.
[0033] The sixteenth lens has an anterior surface curvature radius of 24±0.2mm, a posterior surface curvature radius of -11±0.2mm, a refractive index of 1.58, a dispersion coefficient of 62, an effective aperture of 6±1mm, and a center thickness of 3.6±0.5mm.
[0034] The seventeenth lens has an anterior surface curvature radius of 88.9±0.2mm, a posterior surface curvature radius of -24±0.2mm, a refractive index of 1.6, a dispersion coefficient of 58, an effective aperture of 7.5±1mm, and a center thickness of 3±0.5mm.
[0035] The eighteenth lens has a front surface curvature radius of 24±0.2mm, a rear surface curvature radius of -88.9±0.2mm, a refractive index of 1.6, a dispersion coefficient of 58, an effective aperture of 7.5±1mm, and a center thickness of 3±0.5mm.
[0036] Furthermore, the front surface of the first lens is 270mm from the object surface;
[0037] The distance between the rear surface of the first lens and the front surface of the second lens is 114 mm;
[0038] The distance between the rear surface of the second lens and the front surface of the third lens is 2 mm;
[0039] The distance between the rear surface of the third lens and the front surface of the fourth lens is 18mm;
[0040] The distance from the rear surface of the fourth lens to the center of the beam splitter is 23.2 mm;
[0041] The center of the beam splitter is 25.7 mm from the front surface of the fifth lens;
[0042] The distance between the rear surface of the fifth lens and the front surface of the sixth lens is 8.8 mm;
[0043] The distance between the rear surface of the sixth lens and the front surface of the seventh lens is 21 mm;
[0044] The distance between the rear surface of the seventh lens and the front surface of the eighth lens is 2.3 mm;
[0045] The distance between the rear surface of the ninth lens and the front surface of the tenth lens is 0.2 mm;
[0046] The distance between the rear surface of the tenth lens and the front surface of the eleventh lens is 16.7 mm;
[0047] The rear surface of the eleventh lens is 48mm from the imaging plane.
[0048] Furthermore, the distance between the surface of the object and the front surface of the first lens is 320mm;
[0049] The distance between the rear surface of the first lens and the front surface of the second lens is 114 mm;
[0050] The distance between the rear surface of the second lens and the front surface of the third lens is 2 mm;
[0051] The distance between the rear surface of the third lens and the front surface of the fourth lens is 18mm;
[0052] The distance from the rear surface of the fourth lens to the center of the beam splitter is 23.2 mm;
[0053] The center of the beam splitter is 25.7 mm from the front surface of the twelfth lens;
[0054] The distance between the rear surface of the twelfth lens and the front surface of the thirteenth lens is 8.8 mm;
[0055] The distance between the rear surface of the thirteenth lens and the front surface of the fourteenth lens is 3.5 mm;
[0056] The distance between the rear surface of the fourteenth lens and the front surface of the fifteenth lens is 1.2 mm;
[0057] The distance between the rear surface of the sixteenth lens and the front surface of the seventeenth lens is 0.3 mm;
[0058] The distance between the rear surface of the seventeenth lens and the front surface of the eighteenth lens is 0.9 mm;
[0059] The rear surface of the eighteenth lens is 14.7 mm from the imaging plane.
[0060] Beneficial effects:
[0061] This application provides a dual-field-of-view, dual-working-distance telecentric lens for detection in changing environments, suitable for various detection scenarios, thereby improving the comprehensiveness and accuracy of detection. Light enters through a front optical group, and then a beam splitter divides the incoming light into two beams, which enter a first rear optical group and a second rear optical group respectively. The image is then formed by an imaging device connected to either the first or second rear optical group. Furthermore, the first and second rear optical groups work in conjunction with the front optical group to detect objects at different distances, thus meeting the requirements for detection in changing environments and suitable for various detection scenarios, ultimately improving the comprehensiveness and accuracy of detection. Attached Figure Description
[0062] Figure 1 This is a schematic diagram of a dual-field-of-view, dual-working-distance telecentric lens according to the present invention.
[0063] Figure 2 The MTF diffraction image of the optical group consisting of the front optical group and the first rear optical group;
[0064] Figure 3 The MTF diffraction image of the optical group consisting of the front optical group and the second rear optical group;
[0065] Figure 4 The distortion diagram of the optical group consisting of the front optical group and the first rear optical group;
[0066] Figure 5 This is a distortion diagram of the optical group consisting of the front optical group and the second rear optical group.
[0067] Explanation of reference numerals in the attached figures:
[0068] 1. Front optical group; 11. First lens; 12. Second lens; 13. Third lens; 14. Fourth lens; 2. Beam splitter; 3. First rear optical group; 31. Fifth lens; 32. Sixth lens; 33. Seventh lens; 34. Eighth lens; 35. Ninth lens; 36. Tenth lens; 37. Eleventh lens; 4. Second rear optical group; 41. Twelfth lens; 42. Thirteenth lens; 43. Fourteenth lens; 44. Fifteenth lens; 45. Sixteenth lens; 46. Seventeenth lens; 47. Eighteenth lens. Detailed Implementation
[0069] To make the objectives, technical solutions, and advantages of this application clearer and more explicit, the following detailed description of this application is provided with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.
[0070] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "push-pull" and "open-close" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "push-pull" or "open-close" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.
[0071] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0072] This utility model provides a dual-field-of-view, dual-working-distance telecentric lens. To make the purpose, technical solution, and effects of this utility model clearer and more explicit, the following detailed description is provided with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of this utility model and are not intended to limit it.
[0073] like Figure 1 As shown, a dual-field-of-view, dual-working-distance telecentric lens is used to acquire high-precision and high-resolution images, thereby improving the comprehensiveness and accuracy of detection. It includes a front optical group 1, a beam splitter 2, a first rear optical group 3, and a second rear optical group 4. The front optical group 1 is used to align the object to be photographed and allow light to enter, thereby enabling the imaging of the object captured by the lens and the detection of the generated image. The beam splitter 2 has a first light-inlet end, a first light-outlet end, and a second light-outlet end. The first light-inlet end and the first light-outlet end are located on the same straight line, and the second light-outlet end is perpendicular to the first light-outlet end. The first light-inlet end is located on the light-outlet side of the front optical group 1, the first rear optical group 3 is located on the light-outlet side of the first light-outlet end, and the second rear optical group 4 is located on the light-outlet side of the second light-outlet end.
[0074] In this configuration, the beam splitter 2 is positioned on the side of the front optical group 1 furthest from the object. The beam splitter 2 divides the light entering from the front optical group 1 into two or more groups, which are then transmitted to different imaging devices. In this application, the two groups of light enter the first rear optical group 3 and the second rear optical group 4, respectively. The front optical group 1 and the first rear optical group 3 are aligned on a straight line, maintaining a horizontal orientation. The second rear optical group 4 is perpendicular to the front optical group 1, meaning it is positioned perpendicular to the front optical group 1. The first and second rear optical groups 3 are also perpendicular to each other, thus preventing interference between them. Different imaging requirements are achieved by configuring the first and second rear optical groups 3 and 4. Specifically, the focal length of the optical group formed by the front optical group 1 and the first rear optical group 3 in the horizontal direction is set to f1, the focal length of the optical group formed by the front optical group 1 and the second rear optical group 4 in the vertical direction is set to f2, the focal length of the front optical group 1 is f11, the focal length of the first rear optical group 3 in the horizontal direction is f12, and the focal length of the second rear optical group 4 in the vertical direction is f22. These have the following relationships: 0.3 < |f12 / f11| < 0.4, 0.08 < |f22 / f11| < 0.1, 0.02 < |f11 / f1| < 0.05, 0.05 < |f11 / f2| < 0.1. Furthermore, different focal lengths are obtained by coordinating the first rear optical group 3 and the second rear optical group 4 with the front optical group 1, in order to photograph objects at different distances. In addition, a camera with a 1.1-inch sensor can be connected to the image plane of the front optical group 1 and the first rear optical group 3 in the horizontal direction, and a camera with a 2 / 3-inch sensor can be connected to the image plane of the front optical group 1 and the second rear optical group 4 in the vertical direction. By connecting cameras with different sensor sizes, different imaging requirements can be met. That is, different specifications of cameras can be connected through the dual field of view dual working distance telecentric lens in this application to meet different industrial needs at different working distances.
[0075] Specifically, the front optical group 1 is provided with a first lens 11, a second lens 12, a third lens 13 and a fourth lens 14 along the direction of light incidence. The beam splitter 2 is located on the side of the fourth lens 14 away from the light incidence port. Meanwhile, the first lens 11 and the second lens 12 are biconvex lenses, and the third lens 13 and the fourth lens 14 are biconcave lenses. Furthermore, the first lens 11 has a front surface radius of curvature of 200±0.2mm, preferably 200mm, and a rear surface radius of curvature of -550±2mm, preferably -500mm, where negative numbers indicate that the surface curvature direction is the same as the direction of light incidence, and positive numbers indicate that the surface curvature direction is opposite to the direction of light incidence. It has a refractive index of 1.6, a dispersion coefficient of 58, an effective aperture of 58±1mm, preferably 58mm, and a center thickness of 15±0.5mm, preferably 15mm. The second lens 12 has a front surface radius of curvature of 49±0.2mm, preferably 49mm, and a rear surface radius of curvature of -180±0.2mm, preferably -180mm. It has a refractive index of 1.49, a dispersion coefficient of 81.6, and an effective aperture of 30±1mm. Preferably, the diameter of the first lens is 30mm, and the center thickness of the lens is 17±0.5mm, preferably 17mm. The radius of curvature of the front surface of the third lens 13 is -170.2±0.2mm, preferably -170mm, and the radius of curvature of the rear surface is -222.8±0.2mm, preferably -222.8mm. The refractive index is 1.75, the dispersion coefficient is 45, the effective aperture is 27±1mm, preferably 27mm, and the center thickness of the lens is 7±0.5mm. The radius of curvature of the front surface of the fourth lens 14 is -122.6±0.2mm, the radius of curvature of the rear surface is 55±0.2mm, preferably 55mm, the refractive index is 1.62, the dispersion coefficient is 33, the effective aperture is 15±1mm, preferably 15mm, and the center thickness of the lens is 3±0.5mm. Meanwhile, the beam splitter 2 is a 40mm thick cubic prism.
[0076] The first rear optical group 3 includes seven lenses. Specifically, the first rear optical group 3 is arranged with a fifth lens 31, a sixth lens 32, a seventh lens 33, an eighth lens 34, a ninth lens 35, a tenth lens 36, and an eleventh lens 37 in sequence along the direction of light incidence. The fifth lens 31 is located on the side of the beam splitter 2 away from the fourth lens 14. The fifth lens 31, the sixth lens 32, the ninth lens 35, and the eleventh lens 37 are biconvex lenses, the seventh lens 33 and the eighth lens 34 are biconcave lenses, and the tenth lens 36 is a plano-convex lens. The eighth lens 34 and the ninth lens 35 form a set of cemented doublet lenses.Regarding the parameters of each lens in the first rear optical group 3, the fifth lens 31 has an anterior surface radius of curvature of 333.5±0.2mm, preferably 333.5mm, a rear surface radius of curvature of -111.6±0.2mm, preferably 111.6mm, a refractive index of 1.76, a dispersion coefficient of 28, an effective aperture of 7.5±1mm, preferably 7.5mm, and a center thickness of 4.2±0.5mm, preferably 4.2mm. The sixth lens 32 has an anterior surface radius of curvature of 34.2±0.2mm, preferably 34.2mm, and a rear surface radius of curvature of -255.4±0.2mm, preferably -255.4mm. The seventh lens 33 has a refractive index of 1.51, a dispersion coefficient of 64, an effective aperture of 7.5±1mm (preferably 7.5mm), a center thickness of 6±0.5mm (preferably 6mm), an anterior surface radius of curvature of -30±0.2mm (preferably -30mm), a posterior surface radius of curvature of -44±0.2mm (preferably -44mm), a refractive index of 1.62, a dispersion coefficient of 36, an effective aperture of 11±1mm (preferably 11mm), a center thickness of 3±0.5mm (preferably 3mm), and an anterior surface radius of curvature of -33±0.2mm (preferably -33mm). The eighth lens 34 has an anterior surface radius of curvature of -33±0.2mm (preferably -33mm), a posterior surface radius of curvature of -33±0.2mm (preferably -33mm), a refractive index of 1.62, a dispersion coefficient of 36, an effective aperture of 11±1mm (preferably 11mm), a center thickness of 3±0.5mm (preferably 3mm), and a posterior surface radius of curvature of -33±0.2mm (preferably -33mm). The ninth lens has a front surface curvature radius of 177±0.2mm, preferably 177mm, a refractive index of 1.73, a dispersion coefficient of 25, an effective aperture of 16.5±1mm, preferably 16.5mm, and a center thickness of 7±0.5mm, preferably 7mm. The tenth lens has a front surface curvature radius of 177±0.2mm, preferably 177mm, a rear surface curvature radius of -40.2±0.2mm, preferably -40.2mm, a refractive index of 1.6, a dispersion coefficient of 58, an effective aperture of 16.5±1mm, preferably 16.5mm, and a center thickness of 11±0.5mm, preferably 11mm. Lens 36 has a flat front surface, a rear surface radius of curvature of -66.3±0.2mm (preferably -66.3mm), a refractive index of 1.67, a dispersion coefficient of 47, an effective aperture of 19±1mm (preferably 19mm), and a center thickness of 8±0.5mm (preferably 8mm). Lens 37 has a front surface radius of curvature of 77±0.2mm (preferably 77mm), a rear surface radius of curvature of -155±0.2mm (preferably -155mm), a refractive index of 1.67, a dispersion coefficient of 47, an effective aperture of 21±1mm (preferably 21mm), and a center thickness of 12±0.5mm (preferably 12mm).
[0077] The second rear optical group 4 includes seven lenses. Specifically, the second rear optical group 4 is provided with a twelfth lens 41, a thirteenth lens 42, a fourteenth lens 43, a fifteenth lens 44, a sixteenth lens 45, a seventeenth lens 46 and an eighteenth lens 47 in sequence along the direction of light incidence. The twelfth lens 41 is located on the side of the beam splitter 2.Furthermore, the twelfth lens 41, the thirteenth lens 42, the sixteenth lens 45, the seventeenth lens 46, and the eighteenth lens 47 are biconvex lenses, while the fourteenth lens 43 and the fifteenth lens 44 are biconcave lenses. Regarding the parameters of each lens in the second rear optical group 4, the front surface radius of curvature of the twelfth lens 41 is 333.5±0.2mm, preferably 333.5mm, the rear surface radius of curvature is -111.6±0.2mm, preferably -111.6, the refractive index is 1.76, the dispersion coefficient is 28, and the effective aperture is 7.5±1mm, preferably 7.5mm. The front surface radius of curvature of the thirteenth lens 42 is 12.5±0.2mm, preferably 12.5mm, and the rear surface... The fourteenth lens 43 has a front surface curvature radius of -44.6±0.2mm, preferably -44.6mm, a refractive index of 1.65, a dispersion coefficient of 44, an effective aperture of 4±1mm, preferably 4mm, and a center thickness of 2.5±0.5mm, preferably 2.5mm. The fourteenth lens 43 has a front surface curvature radius of -13±0.2mm, preferably -13mm, a rear surface curvature radius of 12.4±0.2mm, preferably 12.4mm, a refractive index of 1.62, a dispersion coefficient of 36, an effective aperture of 5.5±1mm, preferably 5.5mm, and a center thickness of 2±0.5mm, preferably 2mm. The fifteenth lens 44 has a front surface curvature radius of -8... The sixteenth lens 45 has an anterior surface curvature radius of 24±0.2mm, preferably 24mm, a rear surface curvature radius of -11±0.2mm, preferably -11mm, a refractive index of 1.75, a dispersion coefficient of 25, an effective aperture of 6±1mm, preferably 6mm, and a center thickness of 2±0.5mm, preferably 2mm. The seventeenth lens 46 has an anterior surface curvature radius of 24±0.2mm, preferably 24mm, a rear surface curvature radius of -11±0.2mm, preferably -11mm, a refractive index of 1.58, a dispersion coefficient of 62, an effective aperture of 6±1mm, preferably 6mm, and a center thickness of 3.6±0.5mm, preferably 3.6mm. The radius of curvature of the front surface of the eighteenth lens 47 is 88.9±0.2mm, preferably 88.9mm; the radius of curvature of the rear surface is -24±0.2mm, preferably -24mm; the refractive index is 1.6; the dispersion coefficient is 58; the effective aperture is 7.5±1mm, preferably 7.5mm; and the center thickness of the lens is 3±0.5mm, preferably 3mm.
[0078] In this application, objects at close range are photographed through the cooperation of the front optical group 1, the first rear optical group 3, and the beam splitter 2. Detailed parameters regarding the distances between the lenses in the front optical group 1, the first rear optical group 3, and the beam splitter 2 and the object, as well as the distances between different lenses, are as follows: the front surface of the first lens 11 is 270mm from the object surface; the rear surface of the first lens 11 is 114mm from the front surface of the second lens 12; the rear surface of the second lens 12 is 2mm from the front surface of the third lens 13; the rear surface of the third lens 13 is 18mm from the front surface of the fourth lens 14; and the rear surface of the fourth lens 14 is 18mm from the beam splitter 2. The center of prism 2 is 23.2 mm. The distance between the center of prism 2 and the front surface of the fifth lens 31 is 25.7 mm. The distance between the rear surface of the fifth lens 31 and the front surface of the sixth lens 32 is 8.8 mm. The distance between the rear surface of the sixth lens 32 and the front surface of the seventh lens 33 is 21 mm. The distance between the rear surface of the seventh lens 33 and the front surface of the eighth lens 34 is 2.3 mm. The distance between the rear surface of the ninth lens 35 and the front surface of the tenth lens 36 is 0.2 mm. The distance between the rear surface of the tenth lens 36 and the front surface of the eleventh lens 37 is 16.7 mm. The distance between the rear surface of the eleventh lens 37 and the imaging plane is 48 mm.
[0079] In this application, objects at a relatively long distance are photographed through the cooperation of the front optical group 1, the second rear optical group 4, and the beam splitter 2. Detailed parameters regarding the distances between the objects and the lenses within the front optical group 1, the second rear optical group 4, and the beam splitter 2, as well as the distances between different lenses, are as follows: the distance from the object surface to the front surface of the first lens 11 is 320 mm; the distance from the rear surface of the first lens 11 to the front surface of the second lens 12 is 114 mm; the distance from the rear surface of the second lens 12 to the front surface of the third lens 13 is 2 mm; the distance from the rear surface of the third lens 13 to the front surface of the fourth lens 14 is 18 mm; and the distance from the rear surface of the fourth lens 14 to the center of the beam splitter 2 is... The distance between the center of the beam splitter 2 and the front surface of the twelfth lens 41 is 23.2 mm. The distance between the rear surface of the twelfth lens 41 and the front surface of the thirteenth lens 42 is 8.8 mm. The distance between the rear surface of the thirteenth lens 42 and the front surface of the fourteenth lens 43 is 3.5 mm. The distance between the rear surface of the fourteenth lens 43 and the front surface of the fifteenth lens 44 is 1.2 mm. The distance between the rear surface of the sixteenth lens 45 and the front surface of the seventeenth lens 46 is 0.3 mm. The distance between the rear surface of the seventeenth lens 46 and the front surface of the eighteenth lens 47 is 0.9 mm. The distance between the rear surface of the eighteenth lens 47 and the imaging plane is 14.7 mm.
[0080] like Figures 2 to 5 As shown, these images illustrate specific analytical data using the dual-view, dual-working-distance telecentric lens described in this application. Figure 2This is the MTF (modulation transfer function) diffraction image of the optical group consisting of front optical group 1 and first rear optical group 3, where OTF stands for optical transfer function. Figure 3 The image shows the MTF diffraction pattern of the optical group consisting of the front optical group 1 and the second rear optical group 4. Figure 4 The image shows the distortion diagram of the optical group consisting of the front optical group 1 and the first rear optical group 3. Figure 5 The distortion diagram is for the optical group consisting of the front optical group 1 and the second rear optical group 4.
[0081] In summary, when using the dual-field-of-view, dual-working-distance telecentric lens of this application to photograph and detect close-range objects, an imaging device is connected behind the first rear optical group 3, so that light passes through the front optical group 1, the beam splitter 2, and the first rear optical group 3, and finally enters the imaging device connected to the first rear optical group 3 to generate an image for detection. When photographing and detecting distant objects, an imaging device is connected behind the second rear optical group 4, so that light passes through the front optical group 1, the beam splitter 2, and the second rear optical group 4, and finally enters the imaging device connected to the second rear optical group 4 to generate an image for detection. Alternatively, imaging devices can be connected simultaneously behind the first rear optical group 3 and the second rear optical group 4, respectively, to allow the dual-field-of-view, dual-working-distance telecentric lens of this application to simultaneously photograph close-range and distant objects.
[0082] It should be understood that the application of this utility model is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.
Claims
1. A dual view dual working distance telecentric lens characterized by, The utility model relates to a lens, which comprises: a front optical group for aligning an object to be photographed and allowing light to enter; a light-splitting prism having a first light-in end, a first light-out end and a second light-out end, the first light-in end and the first light-out end being in a straight line, the second light-out end being perpendicular to the first light-out end, the first light-in end being arranged on the light-out side of the front optical group; a first rear optical group arranged on the light-out side of the first light-out end; a second rear optical group arranged on the light-out side of the second light-out end.
2. The dual field dual working distance telecentric lens of claim 1, wherein, The front optical group is provided with a first lens, a second lens, a third lens and a fourth lens along the direction of light incidence, and the light-splitting prism is arranged on the side of the fourth lens away from the light-in opening.
3. The dual field dual working distance telecentric lens of claim 2, wherein, The first and second lenses are biconvex lenses, and the third and fourth lenses are biconcave lenses.
4. The dual field dual working distance telecentric lens of claim 3, wherein, The front surface of the first lens has a radius of curvature of 200±0.2 mm, the back surface has a radius of curvature of -550±2 mm, the refractive index is 1.6, the dispersion coefficient is 58, the effective aperture is 58±1 mm, and the central thickness of the lens is 15±0.5 mm. The front surface of the second lens has a radius of curvature of 49±0.2 mm, the back surface has a radius of curvature of -180±0.2 mm, the refractive index is 1.49, the dispersion coefficient is 81.6, the effective aperture is 30±1 mm, and the central thickness of the lens is 17±0.5 mm. The front surface of the third lens has a radius of curvature of -170.2±0.2 mm, the back surface has a radius of curvature of -222.8±0.2 mm, the refractive index is 1.75, the dispersion coefficient is 45, the effective aperture is 27±1 mm, and the central thickness of the lens is 7±0.5 mm. The front surface of the fourth lens has a radius of curvature of -122.6±0.2 mm, the back surface has a radius of curvature of 55±0.2 mm, the refractive index is 1.62, the dispersion coefficient is 33, the effective aperture is 15±1 mm, and the central thickness of the lens is 3±0.5 mm. The light-splitting prism is a square prism with a thickness of 40 mm.
5. The dual field dual working distance telecentric lens of claim 4, wherein, The first rear optical group is sequentially provided with a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens and an eleventh lens along the direction of light incidence, and the fifth lens is arranged on the side of the light-splitting prism away from the fourth lens.
6. The dual field dual working distance telecentric lens of claim 5, wherein, The fifth, sixth, ninth and eleventh lenses are biconvex lenses, the seventh and eighth lenses are biconcave lenses, the tenth lens is a plano-convex lens, and the eighth and ninth lenses form a double-cemented lens. The front surface of the fifth lens has a radius of curvature of 333.5±0.2 mm, the back surface has a radius of curvature of -111.6±0.2 mm, the refractive index is 1.76, the dispersion coefficient is 28, the effective aperture is 7.5±1 mm, and the central thickness of the lens is 4.2±0.5 mm. The front surface radius of curvature of the sixth lens is 34.2±0.2mm, the back surface radius of curvature is -255.4±0.2mm, the refractive index is 1.51, the dispersion coefficient is 64, the effective aperture is 7.5±1mm, and the center thickness of the lens is 6±0.5mm; The front surface radius of curvature of the seventh lens is -30±0.2mm, the back surface radius of curvature is -44±0.2mm, the refractive index is 1.62, the dispersion coefficient is 36, the effective aperture is 11±1mm, and the center thickness of the lens is 3±0.5mm; The front surface radius of curvature of the eighth lens is -33±0.2mm, the back surface radius of curvature is 177±0.2mm, the refractive index is 1.73, the dispersion coefficient is 25, the effective aperture is 16.5±1mm, and the center thickness of the lens is 7±0.5mm; The front surface radius of curvature of the ninth lens is 177±0.2mm, the back surface radius of curvature is -40.2±0.2mm, the refractive index is 1.6, the dispersion coefficient is 58, the effective aperture is 16.5±1mm, and the center thickness of the lens is 11±0.5mm; The front surface of the tenth lens is a plane, the back surface radius of curvature is -66.3±0.2mm, the refractive index is 1.67, the dispersion coefficient is 47, the effective aperture is 19±1mm, and the center thickness of the lens is 8±0.5mm; The front surface radius of curvature of the eleventh lens is 77±0.2mm, the back surface radius of curvature is -155±0.2mm, the refractive index is 1.67, the dispersion coefficient is 47, the effective aperture is 21±1mm, and the center thickness of the lens is 12±0.5mm.
7. The dual field dual working distance telecentric lens of claim 4, wherein, The second rear optical group is sequentially provided with a twelfth lens, a thirteenth lens, a fourteenth lens, a fifteenth lens, a sixteenth lens, a seventeenth lens and an eighteenth lens along the direction of light incidence, and the twelfth lens is located on the side surface of the light splitting prism.
8. The dual field dual working distance telecentric lens of claim 7, wherein, The twelfth lens, the thirteenth lens, the sixteenth lens, the seventeenth lens and the eighteenth lens are double-convex lenses, and the fourteenth lens and the fifteenth lens The front surface radius of curvature of the twelfth lens is 333.5±0.2mm, the back surface radius of curvature is -111.6±0.2mm, the refractive index is 1.76, the dispersion coefficient is 28, and the effective aperture is 7.5±1mm; The front surface radius of curvature of the thirteenth lens is 12.5±0.2mm, the back surface radius of curvature is -44.6±0.2mm, the refractive index is 1.65, the dispersion coefficient is 44, the effective aperture is 4±1mm, and the center thickness of the lens is 2.5±0.5mm; The front surface radius of curvature of the fourteenth lens is -13±0.2mm, the back surface radius of curvature is 12.4±0.2mm, the refractive index is 1.62, the dispersion coefficient is 36, the effective aperture is 5.5±1mm, and the center thickness of the lens is 2±0.5mm; The front surface radius of curvature of the fifteenth lens is -8.5±0.2mm, the back surface radius of curvature is 24±0.2mm, the refractive index is 1.75, the dispersion coefficient is 25, the effective aperture is 6±1mm, and the center thickness of the lens is 2±0.5mm; The front surface radius of curvature of the sixteenth lens is 24±0.2mm, the back surface radius of curvature is -11±0.2mm, the refractive index is 1.58, the dispersion coefficient is 62, the effective aperture is 6±1mm, and the center thickness of the lens is 3.6±0.5mm; The front surface radius of curvature of the seventeenth lens is 88.9±0.2mm, the back surface radius of curvature is -24±0.2mm, the refractive index is 1.6, the dispersion coefficient is 58, the effective aperture is 7.5±1mm, and the center thickness of the lens is 3±0.5mm; The front surface radius of curvature of the eighteenth lens is 24±0.2mm, the back surface radius of curvature is -88.9±0.2mm, the refractive index is 1.6, the dispersion coefficient is 58, the effective aperture is 7.5±1mm, and the center thickness of the lens is 3±0.5mm.
9. The dual field dual working distance telecentric lens of claim 6, wherein, The front surface of the first lens is 270mm from the object surface; The back surface of the first lens is 114mm from the front surface of the second lens; The back surface of the second lens is 2mm from the front surface of the third lens; The back surface of the third lens is 18mm from the front surface of the fourth lens; The back surface of the fourth lens is 23.2mm from the center of the light splitting prism; The center of the light splitting prism is 25.7mm from the front surface of the fifth lens; The back surface of the fifth lens is 8.8mm from the front surface of the sixth lens; The back surface of the sixth lens is 21mm from the front surface of the seventh lens; The back surface of the seventh lens is 2.3mm from the front surface of the eighth lens; The back surface of the ninth lens is 0.2mm from the front surface of the tenth lens; The back surface of the tenth lens is 16.7mm from the front surface of the eleventh lens; The back surface of the eleventh lens is 48mm from the imaging surface.
10. The dual field dual working distance telecentric lens of claim 8, wherein, The front surface of the first lens is 320mm from the object surface; The back surface of the first lens is 114mm from the front surface of the second lens; The back surface of the second lens is 2mm from the front surface of the third lens; The back surface of the third lens is 18mm from the front surface of the fourth lens; The back surface of the fourth lens is 23.2mm from the center of the light splitting prism; The center of the light splitting prism is 25.7mm from the front surface of the twelfth lens; The back surface of the twelfth lens is 8.8mm from the front surface of the thirteenth lens; The back surface of the thirteenth lens is 3.5mm from the front surface of the fourteenth lens; The back surface of the fourteenth lens is 1.2mm from the front surface of the fifteenth lens; The back surface of the sixteenth lens is 0.3mm from the front surface of the seventeenth lens; The back surface of the seventeenth lens is 0.9mm away from the front surface of the eighteenth lens; The back surface of the eighteenth lens is 14.7mm away from the imaging surface.