3P thin lens for preventing performance degradation after locking and processing method thereof

Abstract

The present invention relates to the technical field of optical lenses, and in particular to a 3P thin lens and a processing method thereof for preventing performance degradation after locking. The 3P thin lens comprises: a lens barrel; the lens barrel comprises a P1-level lens barrel, a P2-level lens barrel and a P3-level lens barrel connected from outside to inside; a P1-level lens is fixed in the P1-level lens barrel, and the P1-level lens is in contact with the bottom of the lens barrel; a P2-level lens is fixed in the P2-level lens barrel; and a P3-level lens is fixed in the P3-level lens barrel. The bottom thickness H of the lens barrel is 0.22-0.25 mm; the thickness B1 of the P1-level lens barrel is (1.56-1.60)×H; the thickness B2 of the P2-level lens barrel is (1.24-1.702)×H; and the thickness B3 of the P3-level lens barrel is (1.14-2.26)×H. The 3P thin lens and processing method thereof for preventing performance degradation after locking provided by the present invention can reduce the bottom thickness of the lens barrel as much as possible while ensuring that the performance of the lens remains unchanged after locking by providing the above formula to stipulate the functional relationship between the bottom thickness H of the lens barrel and the thickness of the third-level lens barrel.

Description

Technical Field

[0001] The present invention relates to the technical field of optical lenses, and in particular to a 3P thin lens capable of preventing performance degradation after locking and a processing method thereof. Background Art

[0002] Optical lenses are essential components in machine vision systems, which directly affect the quality of imaging and the implementation and effect of algorithms. Optical lenses can be divided into short-focus lenses, medium-focus lenses, and long-focus lenses in terms of focal length; wide-angle, standard, and telephoto lenses in terms of field of view; and fixed-aperture fixed-focus lenses, manual-aperture fixed-focus lenses, automatic-aperture fixed-focus lenses, manual-variable-focus lenses, automatic-variable-focus lenses, automatic-aperture electric-variable-focus lenses, and electric three-variable (aperture, focal length, and focus are all variable) lenses in terms of structure. Today, as the TTL requirements for lenses become smaller and smaller, the thickness of the lens barrel is forced to become thinner and thinner. Technically, the thinner the thickness of the lens barrel, the worse the lens structure, which poses new challenges to the design of the lens barrel structure. If the structural design is not good, the lens will fail after locking even if it performs well before locking. Moreover, the factory usually no longer inspects the performance after locking, and it is detected by the customer, resulting in batch returns and huge losses. Summary of the invention

[0003] The present invention aims at the technical problem in the prior art that the performance of an optical lens after locking is easily unqualified after the base thickness is reduced, and provides a 3P thin lens and a processing method thereof for preventing the performance from being deteriorated after locking.

[0004] The technical solution of the present invention to solve the above technical problems is as follows:

[0005] A 3P thin lens for preventing performance degradation after locking, comprising: a lens barrel; the lens barrel comprises a P1-level lens barrel, a P2-level lens barrel and a P3-level lens barrel connected from outside to inside; a P1-level lens is fixed in the P1-level lens barrel, and the P1-level lens abuts against the bottom of the lens barrel; a P2-level lens is fixed in the P2-level lens barrel; and a P3-level lens is fixed in the P3-level lens barrel;

[0006] The bottom thickness H of the lens barrel is 0.22-0.25mm; the thickness B1 of the P1-level lens barrel is (1.56-1.60)×H; the thickness B2 of the P2-level lens barrel is (1.24-1.702)×H; the thickness B3 of the P3-level lens barrel is (1.14-2.26)×H; the matching length PH1 of the P1-level lens and the P1-level lens barrel is (0.458-0.514)×H; the matching length PH2 of the P2-level lens and the P2-level lens barrel is (0.752-1.076)×H.

[0007] Furthermore, the matching length PH3 between the P3 lens and the P3 lens barrel is (0.716-0.805)×H.

[0008] Furthermore, interference fit is adopted between the P1 gear lens and the P1 gear lens barrel, between the P2 gear lens and the P2 gear lens barrel, and between the P3 gear lens and the P3 gear lens barrel.

[0009] Furthermore, the maximum interference between the P1-level lens and the P1-level lens barrel is 5 to 7 μm; the maximum interference between the P2-level lens and the P2-level lens barrel is 5 to 7 μm; and the maximum interference between the P3-level lens and the P3-level lens barrel is 5 to 7 μm.

[0010] The present invention also provides a method for processing a 3P thin lens to prevent performance degradation after locking, comprising the following steps:

[0011] Step S10, taking the bottom thickness H of the lens barrel within the range of 0.22-0.25 mm; calculating the thickness B1 of the lens barrel at P1 level according to the formula B1=(1.56-1.60)×H; calculating the thickness B2 of the lens barrel at P2 level according to the formula B2=(1.24-1.702)×H; calculating the thickness B3 of the lens barrel at P3 level according to the formula B3=(1.14-2.26)×H;

[0012] Step S20, processing the lens barrel according to the selected bottom thickness H of the lens barrel, the calculated values ​​of the lens barrel thickness B1 at the P1 level, the lens barrel thickness B2 at the P2 level, and the lens barrel thickness B3 at the P3 level;

[0013] Step S30, fixing the P1-level lens in the P1-level lens barrel, fixing the P2-level lens in the P2-level lens barrel; fixing the P3-level lens in the P3-level lens barrel.

[0014] Furthermore, the step S30 also includes: controlling the matching length PH1 of the P1 gear lens and the P1 gear lens barrel to be (0.458~0.514)×H; controlling the matching length PH2 of the P2 gear lens and the P2 gear lens barrel to be (0.752~1.076)×H; and controlling the matching length PH3 of the P3 gear lens and the P3 gear lens barrel to be (0.716~0.805)×H.

[0015] Furthermore, the step S30 also includes: controlling the P1-level lens and the P1-level lens barrel, the P2-level lens and the P2-level lens barrel, and the P3-level lens and the P3-level lens barrel to adopt interference fit.

[0016] Furthermore, the step S30 also includes: controlling the maximum interference between the P1 gear lens and the P1 gear lens barrel to be 5-7 μm; controlling the maximum interference between the P2 gear lens and the P2 gear lens barrel to be 5-7 μm; and controlling the maximum interference between the P3 gear lens and the P3 gear lens barrel to be 5-7 μm.

[0017] The 3P thin lens and its processing method for preventing performance degradation after locking provided by the present invention have at least the following beneficial effects or advantages:

[0018] The 3P thin lens and processing method thereof for preventing performance degradation after locking provided by the present invention, wherein a P1-level lens is fixed in a P1-level lens barrel, and the P1-level lens is in contact with the bottom of the lens barrel; a P2-level lens is fixed in a P2-level lens barrel; a P3-level lens is fixed in a P3-level lens barrel; the bottom thickness H of the lens barrel is 0.22-0.25 mm; the thickness B1 of the P1-level lens barrel is (1.56-1.60)×H; the thickness B2 of the P2-level lens barrel is (1.24-1.702)×H; the thickness B3 of the P3-level lens barrel is (1.14-2.26)×H. The 3P thin lens and processing method thereof for preventing performance degradation after locking provided by the present invention, by providing the above formula to stipulate the functional relationship between the bottom thickness H of the lens barrel and the thickness of the three-level lens barrel, can reduce the bottom thickness of the lens barrel as much as possible while ensuring that the performance of the lens remains unchanged after locking. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of a 3P thin lens structure for preventing performance degradation after locking provided by an embodiment of the present invention.

[0020] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0021] 1-P1 gear lens, 2-P2 gear lens, 3-P3 gear lens, 4-P1 gear lens barrel, 5-P2 gear lens barrel, 6-P3 gear lens barrel. DETAILED DESCRIPTION

[0022] The present invention aims at the technical problem in the prior art that the performance of an optical lens after locking is easily unqualified after the base thickness is reduced, and provides a 3P thin lens and a processing method thereof for preventing the performance from being deteriorated after locking.

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Embodiment 1

[0025] See also Figure 1 The embodiment of the present invention provides a 3P thin lens that prevents performance degradation after locking, which mainly includes: a lens barrel; the lens barrel includes a P1-stage lens barrel 4, a P2-stage lens barrel 5, and a P3-stage lens barrel 6 connected from the outside to the inside. A P1-stage lens 1 is fixed in the P1-stage lens barrel 4, and the P1-stage lens 1 abuts against the bottom of the lens barrel; a P2-stage lens 2 is fixed in the P2-stage lens barrel; and a P3-stage lens 3 is fixed in the P3-stage lens barrel 6. The bottom thickness H of the lens barrel is 0.22-0.25mm; the thickness B1 of the P1-stage lens barrel 4 is (1.56-1.60)×H; the thickness B2 of the P2-stage lens barrel 5 is (1.24-1.702)×H; the thickness B3 of the P3-stage lens barrel 6 is (1.14-2.26)×H; wherein, the thickness of each stage lens barrel can be a small value when H is large, and must be a large value when H is small.

[0026] The matching length PH1 of the P1-stage lens 1 and the P1-stage lens barrel 4 is (0.458-0.514)×H. The matching length PH2 of the P2-stage lens 2 and the P2-stage lens barrel 5 is (0.752-1.076)×H. The matching length PH3 of the P3-stage lens 3 and the P3-stage lens barrel 6 is (0.716-0.805)×H; wherein, the matching length of the P1-stage lens 1 and the P1-stage lens barrel 4 can be a small value when H is large, and must be a large value when H is small. .

[0027] Interference fit is adopted between the P1-level lens 1 and the P1-level lens barrel 4, between the P2-level lens 2 and the P2-level lens barrel 5, and between the P3-level lens 3 and the P3-level lens barrel 6. The maximum interference fit between the P1-level lens 1 and the P1-level lens barrel 4 is 5-7 μm; the maximum interference fit between the P2-level lens 2 and the P2-level lens barrel 5 is 5-7 μm; the maximum interference fit between the P3-level lens 3 and the P3-level lens barrel 6 is 5-7 μm.

[0028] Embodiment 2

[0029] See also Figure 1 This embodiment also provides a method for processing a 3P thin lens to prevent performance degradation after locking, comprising the following steps:

[0030] Step S10, the bottom thickness H of the lens barrel is taken within the range of 0.22-0.25 mm; the thickness B1 of the lens barrel 4 at P1 level is calculated according to the formula B1=(1.56-1.60)×H; the thickness B2 of the lens barrel 5 at P2 level is calculated according to the formula B2=(1.24-1.702)×H; the thickness B3 of the lens barrel 6 at P3 level is calculated according to the formula B3=(1.14-2.26)×H.

[0031] Step S20, processing the lens barrel according to the selected bottom thickness H of the lens barrel, the calculated thickness B1 of the lens barrel 4 at P1 level, the thickness B2 of the lens barrel 5 at P2 level, and the thickness B3 of the lens barrel 6 at P3 level.

[0032] Step S30, fixing the P1 lens 1 in the P1 lens barrel 4, fixing the P2 lens 2 in the P2 lens barrel; fixing the P3 lens 3 in the P3 lens barrel 6. To further increase the assembly accuracy, step S30 also includes:

[0033] The matching length PH1 of the P1-level lens 1 and the P1-level lens barrel 4 is controlled to be (0.458~0.514)×H; the matching length PH2 of the P2-level lens 2 and the P2-level lens barrel 5 is controlled to be (0.752~1.076)×H; and the matching length PH3 of the P3-level lens 3 and the P3-level lens barrel 6 is controlled to be (0.716~0.805)×H.

[0034] Interference fit is adopted between the P1 gear lens 1 and the P1 gear lens barrel 4 , between the P2 gear lens 2 and the P2 gear lens barrel 5 , and between the P3 gear lens 3 and the P3 gear lens barrel 6 .

[0035] The maximum interference between the P1-level lens 1 and the P1-level lens barrel 4 is controlled to be 5-7 μm; the maximum interference between the P2-level lens 2 and the P2-level lens barrel 5 is controlled to be 5-7 μm; and the maximum interference between the P3-level lens 3 and the P3-level lens barrel 6 is controlled to be 5-7 μm.

[0036] The following provides specific data to further illustrate this embodiment:

[0037] 0S 0.38S 0.38T 0.7S 0.7T 0.77S 0.77T MTF 72.14 47.80 55.93 47.27 48.29 50.88 42.17 Offset -7.10 0.20 -2.40 -0.50 0.90 -3.60

[0038] Table 1

[0039] 0S 0.38S 0.38T 0.7S 0.7T 0.77S 0.77T MTF 60.10 45.40 22.00 38.20 6.20 29.50 3.30 Offset -3.10 11.00 8.50 17.40 13.70 15.40

[0040] Table 2

[0041] 0S 0.38S 0.38T 0.7S 0.7T 0.77S 0.77T MTF -12.04 -2.40 -33.93 -9.07 -42.09 -21.38 -38.87 Offset 4.00 10.80 10.90 17.90 12.80 19.00

[0042] Table 3

[0043] Table 1 above is the data before locking of the optical lens manufactured by the prior art, Table 2 is the data after locking of the optical lens manufactured by the prior art, and Table 3 is the variation data after locking of the optical lens manufactured by the prior art. It can be seen from Tables 1 to 3 that the performance test before locking is normal, the field curvature is normal, and the vertex is normal. After locking, 0.77T changes from -3.6 to 15.4, the variation is 19NG, the field curvature is seriously positive, and the result is abnormal; MTF drops from 72.14 to 60.1, the variation is 12.04NG, the MTF drops drastically, and the parameters are seriously abnormal.

[0044] 0S 0.38S 0.38T 0.7S 0.7T 0.77S 0.77T MTF 71.72 56.28 55.08 48.14 46.61 46.62 43.07 Offset -6.30 2.30 -0.50 3.10 4.40 1.30

[0045] Table 4

[0046] 0S 0.38S 0.38T 0.7S 0.7T 0.77S 0.77T MTF 72.29 54.02 54.62 57.11 50.56 53.81 46.02 Offset -6.50 1.60 -1.20 2.30 3.30 -0.20

[0047] Table 5

[0048] 0S 0.38S 0.38T 0.7S 0.7T 0.77S 0.77T MTF 0.57 -2.26 -0.46 8.97 3.95 7.19 2.95 Offset -0.20 -0.70 -0.70 -0.80 -1.10 -1.50

[0049] Table 6

[0050] Table 4 is the data before the optical lens provided in this embodiment is locked, Table 2 is the data after the optical lens provided in this embodiment is locked, and Table 3 is the variation data after the optical lens provided in this embodiment is locked. It can be seen from Tables 4 to 6 that the performance test before locking is normal, the field curvature is normal, and the vertex is normal; after locking, 0.77T changes from 1.3 to -0.2, the variation is 1.5, the field curvature changes are not significant, and the measurement error is normal. MTF changes from 71.72 to 72.29, the variation is 0.57, which is a normal measurement error.

[0051] The 3P thin lens and the processing method thereof for preventing performance degradation after locking provided by the embodiments of the present invention have at least the following beneficial effects or advantages:

[0052] The 3P thin lens and processing method thereof for preventing performance degradation after locking provided by the embodiment of the present invention, wherein a P1-level lens is fixed in a P1-level lens barrel, and the P1-level lens is in contact with the bottom of the lens barrel; a P2-level lens is fixed in a P2-level lens barrel; a P3-level lens is fixed in a P3-level lens barrel; the bottom thickness H of the lens barrel is 0.22-0.25mm; the thickness B1 of the P1-level lens barrel is (1.56-1.60)×H; the thickness B2 of the P2-level lens barrel is (1.24-1.702)×H; the thickness B3 of the P3-level lens barrel is (1.14-2.26)×H. The 3P thin lens and processing method thereof for preventing performance degradation after locking provided by the embodiment of the present invention, by providing the above formula to stipulate the functional relationship between the bottom thickness H of the lens barrel and the thickness of the three-level lens barrel, can reduce the bottom thickness of the lens barrel as much as possible while ensuring that the performance of the lens remains unchanged after locking.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A 3P thin lens for preventing performance degradation after locking, comprising: Lens tube; The lens barrel comprises a P1 lens barrel, a P2 lens barrel and a P3 lens barrel connected from outside to inside; A P1-level lens is fixed in the P1-level lens barrel, and the P1-level lens abuts against the bottom of the lens barrel; a P2-level lens is fixed in the P2-level lens barrel; and a P3-level lens is fixed in the P3-level lens barrel; It is characterized in that the bottom thickness H of the lens barrel is 0.22-0.25 mm; the thickness B1 of the lens barrel in the P1 gear is (1.56-1.60)×H; the thickness B2 of the lens barrel in the P2 gear is (1.24-1.702)×H; and the thickness B3 of the lens barrel in the P3 gear is (1.14-2.26)×H.

2. The 3P thin lens for preventing performance degradation after locking according to claim 1, characterized in that: The matching length PH1 of the P1-level lens and the P1-level lens barrel is (0.458~0.514)×H; the matching length PH2 of the P2-level lens and the P2-level lens barrel is (0.752~1.076)×H; the matching length PH3 of the P3-level lens and the P3-level lens barrel is (0.716~0.805)×H.

3. The 3P thin lens for preventing performance degradation after locking according to claim 1 or 2, characterized in that: Interference fit is adopted between the P1 gear lens and the P1 gear lens barrel, between the P2 gear lens and the P2 gear lens barrel, and between the P3 gear lens and the P3 gear lens barrel.

4. The 3P thin lens for preventing performance degradation after locking according to claim 3, characterized in that: The maximum interference between the P1-level lens and the P1-level lens barrel is 5~7μm; the maximum interference between the P2-level lens and the P2-level lens barrel is 5~7μm; the maximum interference between the P3-level lens and the P3-level lens barrel is 5~7μm.

5. A method for processing a 3P thin lens to prevent performance degradation after locking as claimed in claim 1, characterized in that: The steps include: Step S10, taking the bottom thickness H of the lens barrel within the range of 0.22-0.25 mm; calculating the thickness B1 of the lens barrel at P1 according to the formula B1=(1.56-1.60)×H; calculating the thickness B2 of the lens barrel at P2 according to the formula B2=(1.24-1.702)×H; Calculate the thickness B3 of the P3 lens barrel according to the formula B3=(1.14~2.26)×H; Step S20, processing the lens barrel according to the selected bottom thickness H of the lens barrel, the calculated values ​​of the lens barrel thickness B1 at the P1 level, the lens barrel thickness B2 at the P2 level, and the lens barrel thickness B3 at the P3 level; Step S30, fixing the P1-level lens in the P1-level lens barrel, fixing the P2-level lens in the P2-level lens barrel; fixing the P3-level lens in the P3-level lens barrel.

6. The method for processing a 3P thin lens to prevent performance degradation after locking according to claim 5, characterized in that: The step S30 also includes: controlling the matching length PH1 of the P1-level lens and the P1-level lens barrel to be (0.458~0.514)×H; controlling the matching length PH2 of the P2-level lens and the P2-level lens barrel to be (0.752~1.076)×H; and controlling the matching length PH3 of the P3-level lens and the P3-level lens barrel to be (0.716~0.805)×H.

7. The method for processing a 3P thin lens to prevent performance degradation after locking according to claim 5, characterized in that: The step S30 further includes: controlling the P1-level lens and the P1-level lens barrel, the P2-level lens and the P2-level lens barrel, and the P3-level lens and the P3-level lens barrel to adopt interference fit.

8. The method for processing a 3P thin lens to prevent performance degradation after locking according to claim 7, characterized in that: The step S30 also includes: controlling the maximum interference between the P1-level lens and the P1-level lens barrel to be 5-7 μm; controlling the maximum interference between the P2-level lens and the P2-level lens barrel to be 5-7 μm; and controlling the maximum interference between the P3-level lens and the P3-level lens barrel to be 5-7 μm.

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