阅读说明：本技术 一种航天用光学镜头 (Optical lens for spaceflight ) 是由 张新 刘涛 王灵杰 史广维 张建萍 于 2019-11-15 设计创作，主要内容包括：本发明公开一种航天用光学镜头,包括从物方到像方依次排列的第一透镜,第二透镜,第三透镜,第四透镜,第五透镜,第六透镜,光阑,第七透镜,第八透镜,第九透镜,第十透镜,第一透镜与第二透镜均为凸向物方的负弯月透镜,第三透镜为凸向像方的负弯月透镜或者双凹透镜,第四透镜为凸向像方的正弯月透镜,第五透镜为凸向物方的正弯月透镜或者平凸透镜或者双凸透镜,第六透镜为凸向物方的正弯月透镜,第七透镜为双凸透镜,第八透镜为平凹透镜或者双凹透镜,第九透镜为双凸透镜,第十透镜为双凸透镜,所有透镜无胶合,其中第一透镜和第十透镜为单面非球面透镜,由此本发明公开的光学镜头可实现大视场、低畸变、消热差。(The invention discloses an optical lens for spaceflight, which comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a diaphragm, a seventh lens, an eighth lens, a ninth lens and a tenth lens which are sequentially arranged from an object side to an image side, wherein the first lens and the second lens are both negative meniscus lenses convex to the object side, the third lens is a negative meniscus lens or a biconcave lens convex to the image side, the fourth lens is a positive meniscus lens convex to the image side, the fifth lens is a positive meniscus lens or a plano-convex lens or a biconvex lens convex to the object side, the sixth lens is a positive meniscus lens convex to the object side, the seventh lens is a biconvex lens, the eighth lens is a plano-concave lens or a biconcave lens, the ninth lens is a biconvex lens, the tenth lens is a biconvex lens, all the lenses are not cemented, wherein the first lens and the tenth lens are single-sided lenses, therefore, the optical lens disclosed by the invention can realize large view field, low distortion and athermal difference.)

1. An optical lens for aerospace, comprising a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element, a diaphragm, a seventh lens element, an eighth lens element, a ninth lens element and a tenth lens element arranged in order from an object side to an image side, wherein the first lens element is a negative meniscus lens element convex toward the object side, the second lens element is a negative meniscus lens element convex toward the object side, the third lens element is a negative meniscus lens element or a biconcave lens element convex toward the image side, the fourth lens element is a positive meniscus lens element convex toward the image side, the fifth lens element is a positive meniscus lens element convex toward the object side, the sixth lens element is a positive meniscus lens element convex toward the object side, the seventh lens element is a biconvex lens element, the eighth lens element is a plano-concave lens element or a biconcave lens element, the ninth lens element is a biconvex lens element, and the tenth lens element is a biconvex lens element, the surface of the first lens facing the object side and the surface of the tenth lens facing the image side are aspheric surfaces, and all the lenses are of a separated structure.

2. An aerospace optical lens according to claim 1, wherein the first to tenth lenses are all glass or crystalline material.

3. An aerospace optical lens according to claim 2, wherein the first and tenth lenses are both glass single-sided aspheric lenses.

4. An aerospace optical lens according to claim 3, wherein the first lens is a fused silica glass material, the first lens has a refractive index in the range 1.45< n <1.55 and a dispersion in the range 60< v < 70; the refractive index range of the tenth lens is more than 1.45 and less than n and less than 1.65, and the dispersion range is more than 60 and less than v and less than 80.

5. An aerospace optical lens according to claim 2, wherein the second to ninth lenses are all glass.

6. An aerospace optical lens according to claim 5, wherein the second lens has a refractive index in the range 1.75< n <1.95 and a dispersion in the range 20< v < 40; the refractive index range of the third lens is more than 1.65 and less than 1.85, and the dispersion range is more than 40 and less than 60; the refractive index range of the fourth lens is more than 1.65 and less than 1.85, and the dispersion range is more than 25 and less than v and less than 45; the refractive index range of the sixth lens is more than 1.45 and less than 1.65, and the dispersion range is more than 55 and less than 75; the refractive index range of the seventh lens or the ninth lens is more than 1.45 and less than 1.60, and the dispersion range is more than 70 and less than 90; the refractive index range of the eighth lens is more than 1.75 and less than 1.95, and the dispersion range is more than 20 and less than 35; the refractive index range of the ninth lens is more than 1.45 and less than n and less than 1.60, and the dispersion range is more than 70 and less than v and less than 90.

7. An aerospace optical lens according to claim 1, wherein the fifth lens is coated with a long-wavelength-pass filter on the surface facing the object side and a short-wavelength-pass filter on the surface facing the image side.

8. An aerospace optical lens as claimed in claim 1, wherein the aspheric surface has an equation of

Where Z is a height of h from the aspheric surface along the optical axis, c is 1/r, r represents a curvature radius of the mirror surface, k is conic coefficient conc, and A, B, C, D is a high-order aspheric coefficient.

Technical Field

The invention relates to the technical field of optical design, in particular to an optical lens for aerospace.

Background

With the development of aerospace industry to a higher level, aiming at special aerospace activities such as extravehicular activities of astronauts, spacecraft flying environments and the like, a camera device capable of working in the extravehicular space environment needs to be arranged, and an optical system configured by the camera device needs to have the characteristics of large field of view and low distortion, and also needs to ensure that the imaging performance of the camera device can be kept stable under the conditions of aircraft operation rising and falling, severe temperature change, high-flux cosmic radiation and the like, so that the development of an aerospace optical lens with large field of view and low distortion, which comprehensively considers weight, structural impact resistance, temperature stability and radiation resistance, is necessary.

The existing wide-angle optical system mostly adopts a multi-lens refraction type structure, and when the field angle is increased, the structure can be ensured to be compact, but the increase of the field angle of the optical system can bring serious distortion, and the imaging quality of the marginal field is influenced, in order to ensure the imaging quality and low distortion of the camera device, and simultaneously, an enough field angle is reached, the large-field optical lens realizes distortion correction by using a multi-purpose plastic aspheric lens, and the wide-angle mega-pixel vehicle-mounted lens disclosed in the Chinese patent with the application number of CN200910099703.3 comprises two lens groups and a diaphragm, and is sequentially provided with from the object side: a front lens group having a negative optical power, a diaphragm, and a rear lens group having a positive optical power. The front lens group consists of a first lens and a second lens with negative focal power and a third lens with positive focal power; the rear lens group consists of a cemented lens group and a sixth lens with positive focal power, the second lens and the sixth lens are aspheric lenses, at least one surface of the second lens and the sixth lens is provided with an aspheric mirror surface, and aberration correction is carried out by adopting two aspheric lenses made of plastic materials.

However, both surfaces of the lens are aspheric surfaces, which is not beneficial to ensuring the center deviation of the lens in optical processing, and in addition, for the optical lens capable of imaging clearly and working stably in the outer space environment, it is necessary to fully consider that the differences between the temperature, pressure and solar radiation borne by the optical lens and the ground are extremely large, and these factors can cause the refractive index, thickness and other parameters of the refractive optical material to change, thereby causing the change of imaging quality.

Disclosure of Invention

The invention aims to provide an aerospace optical lens with a large view field, low distortion and poor heat dissipation, and aims to solve the problems that in the prior art, an optical lens cannot work for a long time in an outer space environment, and cannot meet the requirements of radiation adaptability and temperature change of the outer space environment and impact vibration of an optical system in a satellite emission process.

The embodiment of the invention provides an aerospace optical lens with a large field of view, low distortion and thermal aberration elimination, which comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a diaphragm, a seventh lens, an eighth lens, a ninth lens and a tenth lens which are sequentially arranged from an object side to an image side, wherein the first lens is a negative meniscus lens convex to the object side, the second lens is a negative meniscus lens convex to the object side, the third lens is a negative meniscus lens or a biconcave lens convex to the image side, the fourth lens is a positive meniscus lens convex to the image side, the fifth lens is a positive meniscus lens or a planoconvex lens or a biconvex lens convex to the object side, the sixth lens is a positive meniscus lens convex to the object side, the seventh lens is a biconvex lens, the eighth lens is a planoconvex lens or a biconcave lens, and the ninth lens are, the tenth lens is biconvex lens, through the refraction of ten lens, can be present the big visual field of camera lens, the surface towards the object space of first lens and the surface towards the image space of tenth lens are the aspheric surface, and the distortion correction is realized to aspheric lens, and all lenses are the disconnect-type structure, compare double cemented lens, and outer space environment non-deformable is fit for long-time outer space work more.

Further, the first to tenth lenses are all glass or crystalline materials.

Furthermore, the first lens and the tenth lens are both glass single-sided aspheric lenses, so that the central deviation of the lenses in optical processing is guaranteed, and various aberrations are well corrected.

Furthermore, the first lens is made of fused quartz glass, the refractive index range of the first lens is 1.45< n <1.55, the dispersion range is 60< v <70, the optical quartz glass with the best optical radiation resistant effect at present enables an optical system to have the advantages of difficult color change under the radiation environment and good radiation shielding effect, meanwhile, the optical quartz glass is used as an excellent optical material, the thermal expansion coefficient is extremely small, the chemical stability is good, bubbles, stripes, uniformity and birefringence can be comparable to those of common optical glass, the optical system aberration can also be corrected, the quartz glass density is also very small, and the light weight of the whole optical lens is also greatly facilitated; the refractive index range of the tenth lens is more than 1.45 and less than n and less than 1.65, and the dispersion range is more than 60 and less than v and less than 80.

Furthermore, the second lens, the third lens and the fourth lens are all made of glass materials.

Further, the refractive index range of the second lens is 1.75< n <1.95, and the dispersion range is 20< v < 40; the refractive index range of the third lens is more than 1.65 and less than 1.85, and the dispersion range is more than 40 and less than 60; the refractive index range of the fourth lens is more than 1.65 and less than 1.85, and the dispersion range is more than 25 and less than v and less than 45; the refractive index range of the sixth lens is more than 1.45 and less than 1.65, and the dispersion range is more than 55 and less than 75; the refractive index range of the seventh lens or the ninth lens is more than 1.45 and less than 1.60, and the dispersion range is more than 70 and less than 90; the refractive index range of the eighth lens is more than 1.75 and less than 1.95, and the dispersion range is more than 20 and less than 35; the refractive index range of the ninth lens is more than 1.45 and less than n and less than 1.60, and the dispersion range is more than 70 and less than v and less than 90.

Furthermore, the surface of the fifth lens facing the object space is plated with a long-wave-pass filter film, the surface of the fifth lens facing the image space is plated with a short-wave-pass filter film, and the two filter films are combined to serve as a band-pass filter.

Further, the equation for the aspheric surface is

In the formula, when the height of the aspheric surface along the optical axis direction is h, the distance from the vertex of the aspheric surface is as high as Z, c is 1/r, r represents the curvature radius of the mirror surface, k is a conic coefficient conc, A, B, C, D is a high-order aspheric coefficient, and the aspheric lens well corrects various aberrations, so that the optical system has good quality, and large-field, low-distortion and high-definition imaging can be realized.

According to the invention, a quasi-image space telecentric light path design technology is adopted to reasonably match lens materials, radiuses, distances and thickness parameters, and according to the trend of a light path, light rays are refracted from an object space position through ten lenses and finally focused at an image space position.

Based on the technical scheme, compared with the prior art, the optical lens for spaceflight provided by the invention has the following advantages:

1. by adopting ten lenses for matching, the refraction of the ten lenses can realize the large view field of the optical lens;

2. the invention provides that the surfaces of the first lens and the tenth lens facing the outside of the lens are both aspheric surfaces, the aspheric surfaces can realize distortion correction, and the single-sided aspheric lens is a single-sided aspheric lens, compared with the double-sided aspheric lens in the prior art, the single-sided aspheric lens is beneficial to ensuring the central deviation of the lens in optical processing and well correcting various aberrations;

3. all lenses of the invention adopt a separated structure, and compared with a double-cemented lens, the lens of the separated structure is not easy to deform in an outer space environment, and can adapt to the complex outer space environment for a longer time;

4. the lens provided by the invention can ensure the imaging definition within the temperature range of-55 ℃ to 70 ℃ through testing by reasonably matching different refractive index ranges and dispersion ranges, and the influence of the temperature range on the temperature change is inhibited, so that the large view field, low distortion and heat difference elimination can be realized;

5. in addition, the lenses in the optical lens are made of glass or crystal materials, wherein the first lens is made of fused quartz glass, is a material with the best optical radiation resistant effect at present, has extremely low thermal expansion coefficient and good chemical stability, so that the optical lens is not easy to change color in a radiation environment, can play a good role in radiation shielding, and has better capacity of resisting space charged particles and ultraviolet radiation;

the optical lens for aviation has good environmental adaptability, and can ensure that the whole camera device can clearly image in a severe space environment.

Drawings

FIG. 1 is a schematic structural diagram of a large-field-of-view, low-distortion and athermal optical lens for aerospace in an embodiment of the invention;

FIG. 2 is a schematic diagram of the F-Theta distortion curve in an embodiment of the present invention;

FIG. 3 is a field curvature diagram in an embodiment of the present invention;

FIG. 4 is a schematic view of MTF curve at-55 ℃ in the example of the present invention;

FIG. 5 is a schematic view of MTF curve at 20 ℃ in the example of the present invention;

FIG. 6 is a schematic graph of MTF curve at 70 ℃ in the example of the present invention.

The lens comprises an L1 lens, a first lens, an L2 lens, a second lens, an L3 lens, a third lens, an L4 lens, a fourth lens, an L5 lens, a fifth lens, an L6 lens, a sixth lens, an L7 lens, a seventh lens, an L8 lens, an eighth lens, an L9 lens, a ninth lens, an L10 lens, a tenth lens, an S lens and a diaphragm.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or intervening elements may also be present.

In addition, it should be noted that the terms of orientation such as left, right, up and down in the embodiments of the present invention are only relative concepts or reference to the normal use state of the product, and should not be considered as limiting. The following describes the implementation of the present invention in detail with reference to specific embodiments.

As shown in fig. 1 to 6, an embodiment of the invention provides an optical lens for aerospace, which reasonably matches lens materials, radii, distances and thickness parameters by using a quasi-image-space telecentric optical path design technology, and according to an optical path direction, left side surfaces of all optical elements in fig. 1 are defined as front surfaces, right side surfaces are defined as rear surfaces, leftmost positions are defined as an object space, and rightmost positions are defined as an image space, and the optical lens includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a diaphragm S, a seventh lens L7, an eighth lens L8, a ninth lens L9 and a tenth lens L10, which are sequentially arranged from the object space to the image space. The first lens L1 is a convex object-side negative meniscus lens, the second lens L2 is a convex object-side negative meniscus lens, the third lens L3 is a biconcave lens, in another embodiment, the third lens L3 is a convex negative meniscus lens facing the image side, the fourth lens L4 is a convex positive meniscus lens facing the image side, the fifth lens L5 is a convex plano-convex lens facing the object side, in another embodiment, the fifth lens L5 is a positive meniscus lens convex toward the object or a plano-convex lens, the sixth lens L6 is a positive meniscus lens convex toward the object, the seventh lens L7 is a biconvex lens, the stop S of the entire optical lens is located between the sixth lens L6 and the seventh lens L7, the eighth lens L8 is a biconcave lens, in another embodiment, the eighth lens L8 is a plano-concave lens, the ninth lens L9 is a biconvex lens, and the tenth lens L10 is a biconvex lens, all of which are separate structures.

In the embodiment of the present invention, the refractive index range of the first lens is 1.45< n <1.55, the dispersion range is 60< v <70, and in the embodiment of the present invention, a fused silica glass material is preferred, the refractive index of the fused silica glass material is 1.458, the dispersion of the fused silica glass material is 67.82, or other glass and crystal materials in the refraction range and the dispersion range are preferred; the refractive index range of the second lens is 1.75< n <1.95, the dispersion range is 20< v <40, the embodiment of the invention preferably adopts a glass material of H-ZF62 type, the refractive index of the glass material is 1.923, the dispersion of the glass material is 20.88, or glass and crystal materials in other refraction ranges and dispersion ranges are preferred; the refractive index range of the third lens is 1.65< n <1.85, the dispersion range is 40< v <60, the embodiment of the invention preferably adopts a glass material of H-LAK53B type, the refractive index is 1.755, the dispersion is 52.34, or glass and crystal materials in other refraction ranges and dispersion ranges are preferred; the refractive index range of the fourth lens is 1.65< n <1.85, the dispersion range is 25< v <45, the embodiment of the invention preferably adopts a glass material of H-LAF4 type, the refractive index of the glass material is 1.750, the dispersion of the glass material is 35.02, or glass and crystal materials in other refraction ranges and dispersion ranges are preferred; the refractive index range of the fifth lens is 1.65< n <1.85, the dispersion range is 25< v <45, the embodiment of the invention preferably adopts a glass material of H-LAF4 type, the refractive index of the glass material is 1.750, the dispersion of the glass material is 35.02, or glass and crystal materials in other refraction ranges and dispersion ranges are preferred; the refractive index of the sixth lens is in a range of 1.45< n6<1.65, the dispersion range is 55< v <75, the embodiment of the invention preferably adopts a glass material of H-K9L type, the refractive index is 1.517, and the dispersion is 64.21, or glass and crystal materials in other refraction ranges and dispersion ranges are preferred; the refractive index range of the seventh lens is 1.45< n <1.60, the dispersion range is 70< v <90, the embodiment of the invention preferably adopts a glass material of H-FK61 type, the refractive index of the glass material is 1.497, the dispersion is 81.59, or glass and crystal materials in other refraction ranges and dispersion ranges are preferred; the refractive index range of the eighth lens is 1.75< n <1.95, the dispersion range is 20< v <35, the embodiment of the invention preferably adopts a glass material of H-ZF52 type, the refractive index is 1.847, the dispersion is 23.79, or glass and crystal materials in other refraction ranges and dispersion ranges are preferred; the refractive index range of the ninth lens is 1.45< n <1.60, the dispersion range is 70< v <90, the embodiment of the invention preferably adopts a glass material of H-FK61 type, the refractive index of the glass material is 1.497, the dispersion is 81.59, or glass and crystal materials in other refractive ranges and dispersion ranges are preferred; the refractive index of the tenth lens is in the range of 1.45< n6<1.65, the dispersion range is 60< v <80, and the embodiment of the invention preferably adopts a glass material of H-QK3L type, the refractive index is 1.487, the dispersion is 70.42, or glass and crystal materials in other refraction ranges and dispersion ranges.

All lens mirror parameters for this example are as follows:

TABLE 1

In the embodiment of the invention, the surface of the fifth lens L5 facing the object side is plated with a long-wave pass filter film, and the surface facing the image side is plated with a short-wave pass filter film.

The object side surface of the first lens L1 and the image side surface of the tenth lens L10 are aspheric

Where Z is a height of h from the aspheric surface along the optical axis, c is 1/r, r represents a curvature radius of the mirror surface, k is conic coefficient conc, and A, B, C, D is a high-order aspheric coefficient.

In this embodiment, the aspheric coefficients k, a, B, and C are as follows:

TABLE 2

Serial number	Type (B)	k	A	B	C
						1	Aspherical surface	0	4.81e-005	-8.84e-008	1.05e-010
20	Aspherical surface	-3.09	0	0	0

The effective focal length of the optical lens in the embodiment is F & ltSUB & gt 3.6mm, F/& ltSUB & gt 4.3, the optical total length is less than 59.0mm, the full field of view reaches 145 degrees, the distortion of the marginal field of view is less than 40%, the module height can be very compact, the weight is light, the imaging definition can be kept in the temperature range of-55 ℃ to 70 ℃, and the optical lens in the embodiment can be used as a refractive optical lens for spaceflight with large field of view, low distortion and heat difference elimination, and can also be used as a high-performance vehicle-mounted wide-angle lens and a monitoring lens.

Fig. 2 is a graph of F-Theta distortion of the aerospace refractive optical lens with large field of view, low distortion and thermal difference elimination according to the embodiment, wherein the horizontal axis is percentage, the vertical axis is field of view, and distortion is distortion when an actual lens images an object, which makes a straight line image as a curve, which is inevitable in actual imaging.

FIG. 3 is a field curvature curve diagram of a large-field-of-view, low-distortion and athermalized refractive optical lens for aerospace according to an embodiment of the invention, wherein the field curvature of the embodiment of the invention is less than 0.072 mm.

Fig. 4 to 6 are MTF curves of the refractive optical lens for aerospace having a large field of view, low distortion, and an athermalization difference, where the horizontal axis represents a spatial frequency in units of: wire pairs per millimeter (lp/mm); the longitudinal axis is the MTF value, the MTF value is used for evaluating the imaging quality of the lens, the value range is 0 to 1.0, the higher the MTF curve is, the straighter the MTF curve is, the better the imaging quality of the lens is, and the stronger the reduction capability of a real image is, the embodiment of the invention takes the MTF curve schematic diagram under the conditions of the temperature of-55 ℃, 20 ℃ and 70 ℃, as can be seen from the graphs of figures 4 to 6, the lens can ensure that the lens component can clearly image on the whole imaging surface under the environment of-55 ℃ to 70 ℃, and the requirement of the heat dissipation difference is met.

The above-mentioned embodiments are only specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive various equivalent modifications, substitutions and improvements within the technical scope of the present invention, and these modifications, substitutions and improvements should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.