Low-cost large-view-field low-light objective lens optical system
The low-cost, large field-of-view low-light objective optical system composed of 7 spherical lenses solves the problem that existing large field-of-view low-light objective optical systems cannot simultaneously meet the requirements of low cost, compact structure and good imaging effect, and realizes large field of view, light size and low illumination imaging.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-21
- Publication Date
- 2026-03-24
AI Technical Summary
Existing large field-of-view low-light objective optical systems cannot simultaneously meet the requirements of low cost, compact structure, and good imaging effect.
A low-cost, wide-field-of-view low-light objective lens optical system consisting of 7 spherical lenses, including a first lens, a cemented triplet lens, and a cemented doublet lens, is used. The lens power is configured in a positive and negative combination to control the light path and distortion. It does not use aspherical design and is suitable for mass production.
It achieves a large field of view and lightweight imaging effect, reduces processing costs, is suitable for mass production, and the lens can collect more energy under low light conditions, providing excellent image quality.
Smart Images
Figure CN224035692U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to optical technology field especially relates to a low cost big field of vision micro light objective optical system. BACKGROUND
[0002] Under the condition of low illumination, micro light objective can effectively obtain target information, thereby improving the visual performance and spatial recognition ability at night. Micro light objective uses natural light at night to construct a scene, and works in a passive mode, so it has good concealment. It is first applied in the military field, and has been widely used in night reconnaissance, aiming, vehicle driving and other battlefield operations. Combined with infrared, laser, radar and other technologies, it can form a complete photoelectric reconnaissance, measurement and early warning system, and become an indispensable part of military equipment.
[0003] Due to the burden of the user needs to be considered, micro light objective usually requires small size, light weight, and also needs to meet the requirements of large objective field of view and relative aperture. Although with the continuous improvement of optical processing technology and detection technology, large field of view micro light objective has added diffraction surface and aspheric surface technology to optimize the traditional system design, but this also leads to a substantial increase in cost.
[0004] In summary, the large field of view micro light objective optical system of the prior art is difficult to meet the requirements of low cost, compact structure and good imaging effect at the same time. UTILITY MODEL CONTENT
[0005] The utility model aims at providing a kind of low cost big field of view micro light objective optical system, to solve the technical problems that the large field of view micro light objective optical system in prior art is difficult to meet the requirements of low cost, compact structure and good imaging effect at the same time.
[0006] To achieve the above-mentioned purpose, the utility model adopts a kind of low cost big field of view micro light objective optical system, including first lens, three cemented lenses and double cemented lenses, the three cemented lenses are arranged on one side of the first lens, and the double cemented lenses are arranged on the side of the three cemented lenses away from the first lens;
[0007] The three cemented lenses include second lens, third lens and fourth lens, the double cemented lenses include fifth lens and sixth lens, the second lens is arranged on one side of the first lens, the third lens is arranged between the second lens and the fourth lens, the fifth lens is arranged on the side of the fourth lens away from the third lens, the sixth lens is arranged on the side of the fifth lens away from the fourth lens, and the side of the sixth lens away from the fifth lens is provided with seventh lens;
[0008] The first lens has positive power, the second lens has positive power, the third lens has negative power, the fourth lens has negative power, the fifth lens has positive power, the sixth lens has positive power, and the seventh lens has negative power.
[0009] The F number of the low-cost large field of view micro-light objective optical system is 1.2, the focal length is 25mm, the maximum distortion is less than 1%, the total optical length is less than 38.15mm, the field of view angle can reach 43.8°, and the working waveband is 0.6-0.9μm.
[0010] The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens are all spherical lenses, and the lenses are all made of glass.
[0011] The front surface of the second lens is provided with an aperture stop.
[0012] The effective focal length F1 of the first lens and the total effective focal length F of the lens satisfy 1.68≤F1 / F≤2.47.
[0013] The effective focal length F2 of the second lens and the total effective focal length F of the lens satisfy 0.68≤F2 / F≤1.17.
[0014] The effective focal length F3 of the third lens and the total effective focal length F of the lens satisfy 1.23≤F3 / F≤1.74.
[0015] The effective focal length F4 of the fourth lens and the total effective focal length F of the lens satisfy -0.71≤F4 / F≤-0.45.
[0016] The effective focal length F5 of the fifth lens and the total effective focal length F of the lens satisfy -1.303≤F5 / F≤-1.06.
[0017] The effective focal length F6 of the sixth lens and the total effective focal length F of the lens satisfy 0.12≤F6 / F≤0.29.
[0018] The effective focal length F7 of the seventh lens and the total effective focal length F of the lens satisfy -0.98≤F7 / F≤-0.83.
[0019] The utility model discloses a low -cost big visual field micro light objective optical system, low -cost big visual field micro light objective optical system is by 7 piece spherical lens composition, has realized big visual field, light volume, has not used aspheric surface, is suitable for batch production, reduces processing cost, lens work wave band range 0.6mu m-0.9mu m, lens F number is 1.2, can realize 10^ (-3) Lx low light condition under the imaging can collect more energy, realizes low illumination imaging, in this way solved the technical problem of big visual field micro light objective optical system in prior art difficult to meet low cost, compact structure and good imaging effect simultaneously. BRIEF DESCRIPTION OF DRAWINGS
[0020] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description, obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without creating labor.
[0021] Figure 1 It is the structure schematic diagram of the low -cost big visual field micro light objective optical system of the utility model.
[0022] Figure 2 It is the MTF curve diagram of the low -cost big visual field micro light objective optical system of the utility model.
[0023] Figure 3 It is the point list diagram of the low -cost big visual field micro light objective optical system of the utility model.
[0024] Figure 4 It is the distortion diagram of the low -cost big visual field micro light objective optical system of the utility model.
[0025] 1-first lens, 2-three cemented lenses, 3-double cemented lens, 4-second lens, 5-third lens, 6-fourth lens, 7-fifth lens, 8-sixth lens, 9-seventh lens. DETAILED DESCRIPTION
[0026] The embodiments of the utility model will be described in detail below, the examples of the embodiments are shown in the drawings, the embodiments described below by referring to the drawings are exemplary, and are intended to explain the utility model, and can not be understood as the limitation of the utility model.
[0027] Please refer to Figures 1-4 Among them, Figure 1 It is the structure schematic diagram of the low -cost big visual field micro light objective optical system of the utility model. Figure 2 It is the MTF curve diagram of the low -cost big visual field micro light objective optical system of the utility model. Figure 3It is the spot diagram of the low-cost large field of view micro light objective optical system. Figure 4 It is the distortion diagram of the low-cost large field of view micro light objective optical system.
[0028] The utility model provides a kind of low-cost large field of view micro light objective optical system, including first lens 1, three cemented lenses 2 and double cemented lenses 3, the three cemented lenses 2 are set in the one side of the first lens 1, the double cemented lenses 3 are set in the one side of the three cemented lenses 2 away from the first lens 1;
[0029] The three cemented lenses 2 include second lens 4, third lens 5 and fourth lens 6, the double cemented lenses 3 include fifth lens 7 and sixth lens 8, the second lens 4 is set in the one side of the first lens 1, the third lens 5 is set between the second lens 4 and the fourth lens 6, the fifth lens 7 is set in the one side of the fourth lens 6 away from the third lens 5, the sixth lens 8 is set in the one side of the fifth lens 7 away from the fourth lens 6, the one side of the sixth lens 8 away from the fifth lens 7 is provided with seventh lens 9;
[0030] The first lens 1 focal power is positive, the second lens 4 focal power is positive, the third lens 5 focal power is negative, the fourth lens 6 focal power is negative;The second lens 4, the third lens 5, the fourth lens 6 constitute the three cemented lenses 2, control light ray entering the trend of lens surface, reduce micro light objective aberration, increase the aperture of micro light objective, to improve system imaging quality.
[0031] The fifth lens 7 focal power is positive, the sixth lens 8 focal power is positive;The fifth lens 7 and the sixth lens 8 constitute the double cemented lenses 3, control light ray entering micro light objective subsequent lens light ray trend, can make light ray gentle transition, reduce the tolerance sensitivity while reducing various aberrations of micro light objective, improve assembly yield.
[0032] The seventh lens 9 focal power is negative, tightens light ray, reduces the chief ray angle of micro light objective, matches the CRA requirement of detector, shortens the optical total length of micro light objective simultaneously, so that the structure of micro light objective is more compact.
[0033] Wherein, the F number of the low-cost large field of view micro light objective optical system is 1.2, focal length is 25mm, maximum distortion is less than 1%, optical total length is less than 38.15mm, field of view angle can reach 43.8°, and working wave band is 0.6 μm~0.9 μm.
[0034] The first lens 1, the second lens 4, the third lens 5, the fourth lens 6, the fifth lens 7, the sixth lens 8 and the seventh lens 9 are all spherical lenses, and the lenses are all made of glass.
[0035] The front surface of the second lens 4 is provided with an aperture stop.
[0036] The effective focal length F1 of the first lens 1 and the total effective focal length F of the lens satisfy the condition: 1.68≤F1 / F≤2.47. The effective focal length of the first lens 1 is set to facilitate the convergence of large-angle light into the system, improve the field angle of the low-light objective lens, and make the diameter of the subsequent lens smaller than the first lens 1, thereby realizing the light volume of the low-light objective lens.
[0037] The effective focal length F2 of the second lens 4 and the total effective focal length F of the lens satisfy the condition: 0.68≤F2 / F≤1.17.
[0038] The effective focal length F3 of the third lens 5 and the total effective focal length F of the lens satisfy the condition: 1.23≤F3 / F≤1.74.
[0039] The effective focal length F4 of the fourth lens 6 and the total effective focal length F of the lens satisfy the condition: -0.71≤F4 / F≤-0.45.
[0040] The effective focal length F5 of the fifth lens 7 and the total effective focal length F of the lens satisfy the condition: -1.303≤F5 / F≤-1.06.
[0041] The effective focal length F6 of the sixth lens 8 and the total effective focal length F of the lens satisfy the condition: 0.12≤F6 / F≤0.29.
[0042] The fifth lens 7 and the sixth lens 8 further converge light, further reduce the system optical aperture, improve the high-order spherical aberration and coma of the fixed-focus lens, and are beneficial to improve the resolution of the low-light objective lens.
[0043] The effective focal length F7 of the seventh lens 9 and the total effective focal length F of the lens satisfy the condition: -0.98≤F7 / F≤-0.83.
[0044] The seventh lens 9 reasonably configures the light trend, controls the distance between the lens and the image plane, is beneficial to provide more assembly space for other optical elements, facilitates the assembly of the fixed-focus lens, and avoids interference between the optical elements, thereby improving the assembly yield of the fixed-focus lens.
[0045] For the specific embodiment, the low-cost large-field micro-light objective optical system is composed of 7 spherical lenses, realizes large field of view, light volume, does not use aspheric surface, is suitable for batch production, reduces processing cost, lens working wavelength range is 0.6-0.9 mu m, lens F number is 1.2, can realize 10^(-3) Lx low light condition imaging, can collect more energy, realizes low-illumination imaging, in this way, the technical problem that the large-field micro-light objective optical system in the prior art is difficult to simultaneously meet low cost, compact structure and good imaging effect is solved.
[0046] The specific implementation parameters of the utility model are shown in Table 1, the F number of the micro-light objective optical system is 1.2, the focal length is 25 mm, the maximum distortion is less than 1%, the total optical length is less than 38.15 mm, the field of view angle can reach 43.8 degrees, and the working wavelength range is 0.6-0.9 mu m.
[0047] Table 1
[0048]
[0049] The low-cost large-field micro-light objective optical system is composed of 7 spherical lenses, realizes large field of view, light volume, does not use aspheric surface, is suitable for batch production, reduces processing cost, lens working wavelength range is 0.6-0.9 mu m, lens F number is 1.2, can realize 10^(-3) Lx low light condition imaging, can collect more energy, realizes low-illumination imaging, in this way, the technical problem that the large-field micro-light objective optical system in the prior art is difficult to simultaneously meet low cost, compact structure and good imaging effect is solved.
[0050] The above disclosed is only a preferred embodiment of the utility model, of course, cannot limit the scope of the utility model, and the person skilled in the art can understand that all or part of the above-mentioned embodiments are realized, and equivalent changes made according to the utility model claims still belong to the scope covered by the utility model.
Claims
1. A low-cost, large field-of-view low-light objective lens optical system, characterized in that, It includes a first lens, a cemented triplet lens, and a cemented doublet lens, wherein the cemented triplet lens is disposed on one side of the first lens, and the cemented doublet lens is disposed on the side of the cemented triplet lens away from the first lens; The cemented triplet lens includes a second lens, a third lens, and a fourth lens; the cemented doublet lens includes a fifth lens and a sixth lens; the second lens is disposed on one side of the first lens; the third lens is disposed between the second lens and the fourth lens; the fifth lens is disposed on the side of the fourth lens away from the third lens; the sixth lens is disposed on the side of the fifth lens away from the fourth lens; and a seventh lens is disposed on the side of the sixth lens away from the fifth lens. The first lens has a positive optical power, the second lens has a positive optical power, the third lens has a negative optical power, the fourth lens has a negative optical power, the fifth lens has a positive optical power, the sixth lens has a positive optical power, and the seventh lens has a negative optical power.
2. The low-cost, large field-of-view low-light objective optical system as described in claim 1, characterized in that, The low-cost, wide-field-of-view low-light objective optical system has an F-number of 1.2, a focal length of 25mm, a maximum distortion of less than 1%, a total optical length of less than 38.15mm, a field of view of up to 43.8°, and a working wavelength of 0.6μm to 0.9μm.
3. The low-cost, large field-of-view low-light objective optical system as described in claim 1, characterized in that, The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are all spherical lenses, and all lenses are made of glass; The front surface of the second lens is provided with an aperture stop.
4. The low-cost, large field-of-view low-light objective optical system as described in claim 1, characterized in that, The effective focal length F1 of the first lens and the total effective focal length F of the lens are: 1.68≤F1 / F≤2.
47.
5. The low-cost, large field-of-view low-light objective optical system as described in claim 1, characterized in that, The effective focal length F2 of the second lens and the total effective focal length F of the lens are: 0.68≤F2 / F≤1.
17.
6. The low-cost, large field-of-view low-light objective optical system as described in claim 1, characterized in that, The effective focal length F3 of the third lens and the total effective focal length F of the lens are: 1.23≤F3 / F≤1.
74.
7. The low-cost, large field-of-view low-light objective optical system as described in claim 1, characterized in that, The effective focal length F4 of the fourth lens and the total effective focal length F of the lens are: -0.71≤F4 / F≤-0.
45.
8. The low-cost, large field-of-view low-light objective optical system as described in claim 1, characterized in that, The effective focal length F5 of the fifth lens and the total effective focal length F of the lens are: -1.303≤F5 / F≤-1.
06.
9. The low-cost, large field-of-view low-light objective optical system as described in claim 1, characterized in that, The effective focal length F6 of the sixth lens and the total effective focal length F of the lens are: 0.12≤F6 / F≤0.
29.
10. The low-cost, large field-of-view low-light objective optical system as described in claim 1, characterized in that, The effective focal length F7 of the seventh lens and the total effective focal length F of the lens are: -0.98≤F7 / F≤-0.83.