Double telecentric optical lens
By designing a dual telecentric optical lens that combines multiple lenses, the problem of insufficient performance of existing lenses is solved, and performance indicators of high resolution, low distortion and excellent depth of field are achieved, meeting the accuracy requirements of precision optical measurement systems.
Patent Information
- Application Number
- CN202510547564.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-28
- Publication Date
- 2025-06-17
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
There are still insufficient performance parameters such as resolution, distortion and depth of field of existing dual telecentric lenses, which affect the measurement accuracy of the precision optical measurement system.
A dual telecentric optical lens is designed to form multiple glued lenses by combining different types of lenses (such as biconvex positive lenses, crescent positive lenses, meniscus negative lenses, etc.), optimizing the structure and materials of the lens to meet specific focal lengths and lens group parameters.
It achieves performance indicators of high resolution, low distortion and excellent depth of field. For example, the object square resolution reaches 6um, distortion ≤0.15%, and the image square MTF ≥0.25@41lp/mm@NA0.1, meeting the needs of precision optical measurement systems.
Smart Images
Figure CN120161597A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of optical lenses, and particularly relates to a double telecentric optical lens. Background Art
[0002] A double telecentric lens is a special optical lens. In a precision optical measurement system, there are some limiting factors in ordinary optical lenses, such as image distortion, errors caused by perspective selection, boundary uncertainty caused by inappropriate light source interference, etc. These problems will affect the measurement accuracy. The double telecentric lens can effectively reduce or even eliminate these problems, so it has become an indispensable component in the precision optical measurement system. However, the performance parameters such as resolution, distortion, and depth of field of existing double telecentric lenses still have deficiencies. Summary of the Invention
[0003] The present invention provides a double telecentric optical lens, which solves the deficiencies of existing double telecentric lenses in performance parameters such as resolution, distortion, and depth of field.
[0004] The technical solution of the present invention is as follows:
[0005] A double telecentric optical lens is provided with a double convex positive lens A, a crescent positive lens B, a double convex positive lens C, a meniscus negative lens D, a double convex positive lens E, a double concave negative lens F, a diaphragm, a double convex positive lens G, a double concave negative lens H, a double concave negative lens I, a double convex positive lens J, and a double convex positive lens K in sequence from the outgoing parallel light to the observed object surface; wherein, the double convex positive lens C and the meniscus negative lens D are glued together to form a glued lens CD, the double convex positive lens E and the double concave negative lens F are glued together to form a glued lens EF, the double convex positive lens G and the double concave negative lens H are glued together to form a glued lens GH, and the double concave lens I and the double convex positive lens J are glued together to form a glued lens IJ.
[0006] Preferably, the double convex positive lens A is made of H-K5 glass, the crescent positive lens B is made of H-ZK1 glass, the double convex positive lens C is made of H-ZK6 glass, the meniscus negative lens D is made of H-ZF52A glass, the double convex positive lens E is made of H-ZF72A glass, and the double concave negative lens F is made of H-ZF7LA glass.
[0007] Preferably, the double convex positive lens G is made of H-ZBAF5 glass, the double concave negative lens H is made of H-ZLAF69 glass, the double concave negative lens I is made of H-ZLAF69 glass, the double convex positive lens J is made of H-LAK2A glass, and the double convex positive lens K is made of H-K8 glass.
[0008] Preferably, the focal length f of the double convex positive lens A A satisfies: 100mm < f A < 150mm.
[0009] Preferably, the focal length f of the biconvex positive lens B B satisfies: 200 mm < f B < 250 mm.
[0010] Preferably, the focal length f of the biconvex positive lens K K satisfies: 10 mm < f K < 100 mm.
[0011] Preferably, the focal length f of the cemented lens CD CD satisfies: -150 mm < f CD < -100 mm.
[0012] Preferably, the focal length f of the cemented lens EF EF satisfies: 100 mm < f EF < 200 mm.
[0013] Preferably, the focal length f of the cemented lens GH GH satisfies: -100 mm < f GH < -10 mm.
[0014] Preferably, the focal length f of the cemented lens IJ IJ satisfies: -100 mm < f IJ < -10 mm.
[0015] The double telecentric lens of the present invention can achieve the following beneficial effects:
[0016] Wavelength used: 490 - 580 nm, with a central wavelength of 530 nm;
[0017] Object-side numerical aperture: two gears of 0.05 / 0.11, manually switchable;
[0018] Object-side field of view: ≥ 8 mm;
[0019] Object-side telecentricity: ≤ 0.2°;
[0020] Image-side telecentricity: ≤ 1°;
[0021] Image-side MTF: ≥ 0.25 @ 41 lp / mm @ NA0.1;
[0022] Distortion: ≤ 0.15% @ NA0.1;
[0023] Magnification: 3.5X ± 0.1 times;
[0024] Object-side resolution: 6 μm @ NA0.1;
[0025] Optical lens group transmittance: ≥ 80%. Description of the Drawings
[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.
[0027] Figure 1 Schematic structural diagram of the optical system of the present invention;
[0028] Figure 2 Image-space telecentricity diagram of Embodiment 1;
[0029] Figure 3 Distortion diagram of Embodiment 1;
[0030] Figure 4 Image-space MTF diagram of Embodiment 2;
[0031] Figure 5 Wavefront error diagram of Embodiment 2;
[0032] Figure 6 Distortion diagram of Embodiment 3;
[0033] Figure 7 Wavefront error diagram of Embodiment 3.
[0034] In the figure: 1 - Double-convex positive lens A, 2 - Meniscus positive lens B, 3 - Double-convex positive lens C, 4 - Meniscus negative lens D, 5 - Double-convex positive lens E, 6 - Double-concave negative lens F, 7 - Double-convex positive lens G, 8 - Double-concave negative lens H, 9 - Double-concave negative lens I, 10 - Double-convex positive lens J, 11 - Double-convex positive lens K, 12 - Cemented lens CD, 13 - Cemented lens EF, 14 - Cemented lens GH, 15 - Cemented lens IJ, 16 - Diaphragm. Detailed implementation manners
[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.
[0036] Refer to Figure 1, A double telecentric optical lens is provided with a double convex positive lens A1, a crescent positive lens B2, a double convex positive lens C3, a meniscus negative lens D4, a double convex positive lens E5, a double concave negative lens F6, a diaphragm 16, a double convex positive lens G7, a double concave negative lens H8, a double concave negative lens I9, a double convex positive lens J10, and a double convex positive lens K11 in sequence from the outgoing parallel light to the observed object surface; among them, the double convex positive lens C3 and the meniscus negative lens D4 are glued together to form a glued lens CD12, the double convex positive lens E5 and the double concave negative lens F6 are glued together to form a glued lens EF13, the double convex positive lens G7 and the double concave negative lens H8 are glued together to form a glued lens GH14, and the double concave lens I9 and the double convex positive lens J10 are glued together to form a glued lens IJ15.
[0037] Preferably, the double convex positive lens A is made of H-K5 glass, the crescent positive lens B is made of H-ZK1 glass, the double convex positive lens C is made of H-ZK6 glass, the meniscus negative lens D is made of H-ZF52A glass, the double convex positive lens E is made of H-ZF72A glass, and the double concave negative lens F is made of H-ZF7LA glass.
[0038] Preferably, the double convex positive lens G is made of H-ZBAF5 glass, the double concave negative lens H is made of H-ZLAF69 glass, the double concave negative lens I is made of H-ZLAF69 glass, the double convex positive lens J is made of H-LAK2A glass, and the double convex positive lens K is made of H-K8 glass.
[0039] Preferably, the focal length f of the double convex positive lens A A satisfies: 100mm < f A < 150mm.
[0040] Preferably, the focal length f of the crescent positive lens B B satisfies: 200mm < f B < 250mm.
[0041] Preferably, the focal length f of the double convex positive lens K K satisfies: 10mm < f K < 100mm.
[0042] Preferably, the focal length f of the glued lens CD CD satisfies: -150mm < f CD < -100mm.
[0043] Preferably, the focal length f of the glued lens EF EF satisfies: 100mm < f EF < 200mm.
[0044] Preferably, the focal length f of the glued lens GH GH satisfies: -100mm < fGH < - 10 mm.
[0045] Preferably, the focal length f of the cemented lens IJ IJ satisfies: - 100 mm < f IJ < - 10 mm.
[0046] The dual telecentric lens of the present invention can achieve the following technical specifications:
[0047] Wavelength used: 490 - 580 nm, with a central wavelength of 530 nm;
[0048] Object space numerical aperture: two gears of 0.05 / 0.11, manual switching;
[0049] Object space field of view: ≥ 8 mm;
[0050] Object space telecentricity: ≤ 0.2°;
[0051] Image space telecentricity: ≤ 1°;
[0052] Image space MTF: ≥ 0.25 @ 41 lp / mm @ NA0.1;
[0053] Distortion: ≤ 0.15% @ NA0.1;
[0054] Magnification: 3.5X ± 0.1 times;
[0055] Object space resolution: 6 um @ NA0.1;
[0056] Optical lens group transmittance: ≥ 80%.
[0057] Example 1
[0058] A dual telecentric optical lens is provided with a double convex positive lens A1, a crescent positive lens B2, a double convex positive lens C3, a meniscus negative lens D4, a double convex positive lens E5, a double concave negative lens F6, a diaphragm 16, a double convex positive lens G7, a double concave negative lens H8, a double concave negative lens I9, a double convex positive lens J10, and a double convex positive lens K11 in sequence from the outgoing parallel light to the observed object surface; among them, the double convex positive lens C3 and the meniscus negative lens D4 are cemented together to form a cemented lens CD12, the double convex positive lens E5 and the double concave negative lens F6 are cemented together to form a cemented lens EF13, the double convex positive lens G7 and the double concave negative lens H8 are cemented together to form a cemented lens GH14, and the double concave lens I9 and the double convex positive lens J10 are cemented together to form a cemented lens IJ15.
[0059] Among them, the double convex positive lens A1 is made of H-K5 glass, the crescent positive lens B2 is made of H-ZK1 glass, the double convex positive lens C3 is made of H-ZK6 glass, the meniscus negative lens D4 is made of H-ZF52A glass, the double convex positive lens E5 is made of H-ZF72A glass, the double concave negative lens F6 is made of H-ZF7LA glass, the double convex positive lens G7 is made of H-ZBAF5 glass, the double concave negative lens H8 is made of H-ZLAF69 glass, the double concave negative lens I9 is made of H-ZLAF69 glass, the double convex positive lens J10 is made of H-LAK2A glass, and the double convex positive lens K11 is made of H-K8 glass.
[0060] Among them, the focal length f of the double convex positive lens A1 A Satisfies: f A = 127.02 mm.
[0061] Among them, the focal length f of the double convex positive lens B2 B Satisfies: f B = 227.83 mm.
[0062] Among them, the focal length f of the double convex positive lens K11 K Satisfies: f K = 58.05 mm.
[0063] Among them, the focal length f of the cemented lens CD12 CD Satisfies: f CD = -121.28 mm.
[0064] Among them, the focal length f of the cemented lens EF13 EF Satisfies: f EF = 154.42 mm.
[0065] Among them, the focal length f of the cemented lens GH14 GH Satisfies: f GH = -50.47 mm.
[0066] Among them, the focal length f of the cemented lens IJ15 IJ Satisfies: f IJ = -50.20 mm.
[0067] The lens distribution and detailed parameters of this embodiment are shown in Table 1
[0068] Table 1
[0069]
[0070] The double telecentric optical lens of this embodiment can achieve the following technical indicators;
[0071] Wavelength range: 490 - 580 nm, and the central wavelength is 530 nm;
[0072] Object-side numerical aperture: 0.05 / 0.1 in two gears, manually switchable;
[0073] Object-side field of view: ≥8 mm;
[0074] Object-side telecentricity: ≦0.2°;
[0075] Image-side telecentricity: ≦1°, as Figure 2 shown, it can be seen that the telecentric angle of the full field of view is less than 0.2 degrees, meeting the index requirements;
[0076] Image-side MTF: ≥0.25 @ 50 lp / mm @ NA0.1;
[0077] Distortion: 0.034% @ NA0.1, as Figure 3 shown, this result indicates that the optical distortion of the double telecentric lens is extremely low, meaning that the imaging distortion degree of this lens group is very small;
[0078] Magnification: 3.5X;
[0079] Object-side resolution: 6 um @ NA0.1;
[0080] Optical lens group transmittance: ≥80%.
[0081] Embodiment 2
[0082] A double telecentric optical lens is successively provided with a double convex positive lens A1, a crescent positive lens B2, a double convex positive lens C3, a meniscus negative lens D4, a double convex positive lens E5, a double concave negative lens F6, a diaphragm 16, a double convex positive lens G7, a double concave negative lens H8, a double concave negative lens I9, a double convex positive lens J10, and a double convex positive lens K11 from the outgoing parallel light to the observed object surface; among them, the double convex positive lens C3 and the meniscus negative lens D4 are glued together to form a glued lens CD12, the double convex positive lens E5 and the double concave negative lens F6 are glued together to form a glued lens EF13, the double convex positive lens G7 and the double concave negative lens H8 are glued together to form a glued lens GH14, and the double concave lens I9 and the double convex positive lens J10 are glued together to form a glued lens IJ15.
[0083] Among them, the double convex positive lens A1 is made of H-K5 glass, the crescent positive lens B2 is made of H-ZK1 glass, the double convex positive lens C3 is made of H-ZK6 glass, the meniscus negative lens D4 is made of H-ZF52A glass, the double convex positive lens E5 is made of H-ZF72A glass, the double concave negative lens F6 is made of H-ZF7LA glass, the double convex positive lens G7 is made of H-ZBAF5 glass, the double concave negative lens H8 is made of H-ZLAF69 glass, the double concave negative lens I9 is made of H-ZLAF69 glass, the double convex positive lens J10 is made of H-LAK2A glass, and the double convex positive lens K11 is made of H-K8 glass.
[0084] Among them, the focal length f of the biconvex positive lens A1 A satisfies: f A = 127.03 mm.
[0085] Among them, the focal length f of the biconvex positive lens B2 B satisfies: f B = 227.83 mm.
[0086] Among them, the focal length f of the biconvex positive lens K11 K satisfies: f K = 57.79 mm.
[0087] Among them, the focal length f of the cemented lens CD12 CD satisfies: f CD = -121.13 mm.
[0088] Among them, the focal length f of the cemented lens EF13 EF satisfies: f EF = 154.62 mm.
[0089] Among them, the focal length f of the cemented lens GH14 GH satisfies: f GH = -50.89 mm.
[0090] Among them, the focal length f of the cemented lens IJ15 IJ satisfies: f IJ = -49.81 mm.
[0091] The lens distribution and detailed parameters of this embodiment are shown in Table 2:
[0092] Table 2
[0093]
[0094] The double telecentric optical lens of this embodiment can achieve the following technical indicators:
[0095] Wavelength range: 490 - 580 nm, with a central wavelength of 530 nm;
[0096] Object-side numerical aperture: 0.05 / 0.1 two gears, manual switching;
[0097] Object-side field of view: ≥ 8 mm;
[0098] Object-side telecentricity: ≤ 0.2°;
[0099] Image-side telecentricity: ≤ 1°;
[0100] Image-space MTF: ≥0.25 @ 50 lp / mm @ NA0.1, as Figure 4 shown;
[0101] Distortion: 0.034% @ NA0.1;
[0102] Wavefront error: RMS < 0.05λ, as Figure 5 shown, it can be seen that the RMS wavefront error within the field of view is less than 0.025λ;
[0103] Magnification: 3.5X;
[0104] Object-space resolution: 6um @ NA0.1;
[0105] Transmittance of the optical lens group: ≥80%.
[0106] Example 3
[0107] A double telecentric optical lens is provided with a double convex positive lens A1, a crescent positive lens B2, a double convex positive lens C3, a meniscus negative lens D4, a double convex positive lens E5, a double concave negative lens F6, a diaphragm 16, a double convex positive lens G7, a double concave negative lens H8, a double concave negative lens I9, a double convex positive lens J10, and a double convex positive lens K11 in sequence from the outgoing parallel light to the observed object surface; among them, the double convex positive lens C3 and the meniscus negative lens D4 are glued together to form a glued lens CD12, the double convex positive lens E5 and the double concave negative lens F6 are glued together to form a glued lens EF13, the double convex positive lens G7 and the double concave negative lens H8 are glued together to form a glued lens GH14, and the double concave lens I9 and the double convex positive lens J10 are glued together to form a glued lens IJ15.
[0108] Among them, the double convex positive lens A1 is made of H-K5 glass, the crescent positive lens B2 is made of H-ZK1 glass, the double convex positive lens C3 is made of H-ZK6 glass, the meniscus negative lens D4 is made of H-ZF52A glass, the double convex positive lens E5 is made of H-ZF72A glass, the double concave negative lens F6 is made of H-ZF7LA glass, the double convex positive lens G7 is made of H-ZBAF5 glass, the double concave negative lens H8 is made of H-ZLAF69 glass, the double concave negative lens I9 is made of H-ZLAF69 glass, the double convex positive lens J10 is made of H-LAK2A glass, and the double convex positive lens K11 is made of H-K8 glass.
[0109] Among them, the focal length f of the double convex positive lens A1 A satisfies: f A = 127.01mm.
[0110] Among them, the focal length f of the double convex positive lens B2 B satisfies: f B = 227.81mm.
[0111] Among them, the focal length f of the biconvex positive lens K11 K satisfies: f K = 57.54 mm.
[0112] Among them, the focal length f of the cemented lens CD12 CD satisfies: f CD = -121.08 mm.
[0113] Among them, the focal length f of the cemented lens EF13 EF satisfies: f EF = 154.62 mm.
[0114] Among them, the focal length f of the cemented lens GH14 GH satisfies: f GH = -50.92 mm.
[0115] Among them, the focal length f of the cemented lens IJ15 IJ satisfies: f IJ = -49.58 mm.
[0116] The lens distribution and detailed parameters of this embodiment are shown in Table 3:
[0117] Table 3
[0118]
[0119] The double telecentric optical lens of this embodiment can achieve the following technical indicators:
[0120] Wavelength range: 490 - 580 nm, with a central wavelength of 530 nm;
[0121] Object-side numerical aperture: 0.05 / 0.1 two gears, manual switching;
[0122] Object-side field of view: ≥ 8 mm;
[0123] Object-side telecentricity: ≤ 0.2°;
[0124] Image-side telecentricity: ≤ 1°;
[0125] Image-side MTF: ≥ 0.25 @ 50 lp / mm @ NA0.1;
[0126] Distortion: 0.035% @ NA0.1, as Figure 6 shown;
[0127] Wavefront error: RMS < 0.05λ, as Figure 7 shown, it can be seen that the RMS wavefront error within the field of view is less than 0.025λ;
[0128] Magnification: 3.5X;
[0129] Object-side resolution: 6um @ NA0.1;
[0130] Transmittance of the optical lens group: ≥80%.
[0131] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.
Claims
1. A bi-telecentric optical lens, characterized in that: From the outgoing parallel light to the observed object surface, there are arranged in sequence a biconvex positive lens A, a crescent positive lens B, a biconvex positive lens C, a meniscus negative lens D, a biconvex positive lens E, a biconcave negative lens F, an aperture, a biconvex positive lens G, a biconcave negative lens H, a biconcave negative lens I, a biconvex positive lens J and a biconvex positive lens K; Among them, the biconvex positive lens C and the meniscus negative lens D are cemented together to form a cemented lens CD, the biconvex positive lens E and the biconcave negative lens F are cemented together to form a cemented lens EF, the biconvex positive lens G and the biconcave negative lens H are cemented together to form a cemented lens GH, and the biconcave lens I and the biconvex positive lens J are cemented together to form a cemented lens IJ.
2. A bi-telecentric optical lens as claimed in claim 1, characterized in that: The focal length f of the biconvex positive lens A is A Meet: 100mm <f A <150mm.
3. A bi-telecentric optical lens as claimed in claim 1, characterized in that: The focal length f of the biconvex positive lens B is B Meet: 200mm <f B <250mm.
4. A bi-telecentric optical lens as claimed in claim 1, characterized in that: The focal length f of the biconvex positive lens K is K Meet: 10mm <f K <100mm.
5. The bi-telecentric optical lens according to claim 1, characterized in that: The focal length f of the cemented lens CD CD Meets: -150mm <f CD <-100mm.
6. The bi-telecentric optical lens according to claim 1, characterized in that: The focal length f of the cemented lens EF EF Meet: 100mm <f EF <200mm.
7. The bi-telecentric optical lens according to claim 1, characterized in that: The focal length f of the cemented lens GH GH Meets: -100mm <f GH <-10mm.
8. The bi-telecentric optical lens according to claim 1, characterized in that: The focal length f of the cemented lens IJ IJ Meets: -100mm <f IJ <-10mm.