119 results about "Athermalization" patented technology

The invention provides an infrared target simulator focusing collimation projection optical system and a design method thereof. The optical system is composed of a telescope objective, an intermediate field lens and a relay lens group. A source target and a background image generated by the infrared target simulator are input into the DMD and then are incident to the focusing collimation projection optical system through the DMD, the incident light firstly passes through the relay lens group and the intermediate field lens to generate a primary image of the image on the DMD, and then the primary image surface is collimated and projected to an entrance pupil of a tested photoelectric device through the telescope objective. According to the invention, optical material parameters are finely analyzed and matched, three infrared optical materials are adopted to form a lens group, a field lens is added to compress the aperture of a light beam, and only five lenses are used, so that achromatism and athermalization are realized while high transmittance is ensured. And a focusing lens group and a precise mechanical structure are arranged in the relay lens group, so that the target simulation requirement of photoelectric detection equipment such as a guide head at a wider working temperature range is met, and meanwhile, the requirement of obtaining a clear simulation target scene by matching detected photoelectric equipment with different working distances can be met.

The invention discloses an optical system of an infrared thermal imager, and the system comprises a super-structure lens module which employs a silicon-based super-structure lens, and achieves 3-5 [mu] m and 8-12 [mu] m multi-band focusing through a single sheet; the free-form surface lens is matched with the super-structure lens to correct asymmetric aberration; the multi-view-field switching mechanism is used for driving a zoom group through a micro stepping motor to realize switching between a wide angle and a narrow angle; the active athermalization compensation unit comprises an MEMS driver and a temperature sensor, and the lens spacing is dynamically adjusted through closed-loop control; and the intelligent processing module is integrated with an embedded FPGA processor and operates a deconvolution algorithm to suppress diffraction stray light at the edge of the super-structure lens. According to the optical system of the infrared thermal imager, the problems that a traditional infrared optical system is large in size, high in weight and poor in environmental adaptability are solved through the innovative optical design and manufacturing process, and efficient and long-time patrol flight detection of the unmanned aerial vehicle-mounted infrared thermal imager is achieved.

The invention relates to a broadband short-wave infrared athermalization optical system. The optical system is a transmission type optical system. The structure of the optical system is a coaxial structure; the optical system is provided with a first positive lens, a first negative lens, a second positive lens, a second negative lens and a third negative lens in sequence in the light incidence direction. Light rays are converged through the lenses and are incident on the focal plane of the detector. According to the optical system provided by the invention, only five common infrared optical material lenses are used and matched with an aluminum alloy lens cone material, confocal imaging in a broadband range of 1.0 mu m-2. 5 mu m can be realized, the relative aperture is not greater than 1 / 0.4, athermalization of the optical system is realized, and the optical system is easy to manufacture, high in imaging quality and good in stability.

The invention relates to a small-sized light-weight large-target-surface infrared athermalization optical system, and the optical system consists of a first meniscus positive lens, a meniscus negative lens, a second meniscus positive lens and a third meniscus positive lens which are sequentially and coaxially arranged from an object side to an image side, the second meniscus positive lens and the third meniscus positive lens are the same lens, the first meniscus positive lens, the second meniscus positive lens and the third meniscus positive lens are all made of chalcogenide glass IRG206, and the optical system ensures that edge imaging is clear and the image surface diameter reaches 20mm through optimal arrangement of focal power and optical materials of all the lenses and intervals among all the lenses, so that the image quality is improved. The long-wave infrared imaging device can adapt to a 1280 * 1024 array and a long-wave uncooled infrared detector with the pixel size of 12 microns, and has the advantages of high imaging quality, small size and light weight.

This application discloses an imaging device with an operating temperature range of -40℃ to +60℃, comprising a 4K high-definition lens and a detector for receiving images captured by the 4K high-definition lens. The 4K high-definition lens has a focal length of 50mm, a relative aperture of 1.25, and operates in dual bands: 0.43~0.656μm and 0.7~1μm. The detector has a pixel count of 3840×2160 and a pixel size of 2.9μm. The 4K high-definition lens employs a heat-free design using domestically produced spherical glass, resulting in a simple, compact structure and small size. It utilizes a high-dispersion material lens and a low-dispersion material glass bonded together to achieve dispersion matching. The combination of different lenses and the rational allocation of optical power ensure excellent optical performance. Furthermore, it is suitable for imaging in high-brightness daytime and low-light nighttime environments and can switch bands for imaging, ensuring clear images both day and night.

The invention relates to an athermalization optical system. The system comprises a protection window, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an optical filter, a detector window and an image plane which are sequentially arranged in the light propagation direction and share the same optical axis. The first lens is a negative meniscus lens protruding towards the object side. The second lens is a biconcave lens; the third lens is a biconvex lens; the fourth lens is a positive meniscus lens protruding towards the object side. The fifth lens is a negative meniscus lens protruding towards the object side. The sixth lens is a biconvex lens; the seventh lens is a biconcave lens; the eighth lens is a biconvex lens; the ninth lens is a negative meniscus lens protruding towards the image space. The tenth lens is a biconvex lens; the surface of each lens is a spherical surface; the diaphragm is arranged on the front surface of the sixth lens. The optical system has the advantages of large field of view, high-resolution imaging, simple and reliable structure, high assembly efficiency and capability of being produced on a large scale.

The invention relates to the technical field of optical imaging, in particular to a low-cost large-aperture high-definition vehicle-mounted lens and an imaging method thereof.The optical system of the lens is composed of a first lens body, a second lens body, a third lens body, a diaphragm, a fourth lens body, a fifth lens body and a sixth lens body which are sequentially arranged from the object side to the image side along the optical axis; wherein the first lens, the second lens, the third lens, the fourth lens and the fifth lens are glass spherical lenses, and the sixth lens is a glass aspheric lens. The lens material is reasonably selected, and the focal power, the surface type and the diaphragm position of each lens are reasonably distributed, so that the lens has the advantages of large aperture, high resolution, athermalization function, large clear aperture, high light transmission capability and bright and clear imaging pictures in different light environments; meanwhile, short-wave chromatic aberration is considered, and it is guaranteed that the imaging picture does not have the purple edge phenomenon.

The invention discloses an aviation surveying and mapping lens optical system and a lens, particularly discloses a long-focal-length passive athermalization aviation surveying and mapping lens optical system and a lens, and solves the problems that an existing aviation surveying and mapping lens cannot meet the requirements of long-distance and high-precision surveying and mapping and cannot have long focal length, miniaturization and wide temperature adaptability at the same time. The lens optical system comprises a primary lens, a diaphragm, a secondary lens and an aberration correction lens group, the diaphragm is arranged on a reflection light path of the primary mirror; the secondary mirror is arranged on one side, deviating from the primary mirror, of the diaphragm; the aberration correction lens group is arranged in the central through hole of the primary lens; light in a target area enters the primary mirror, passes through the diaphragm to enter the secondary mirror after being reflected by the primary mirror, reversely passes through the diaphragm to enter the aberration correction mirror group after being reflected by the secondary mirror, and then is imaged; the curvature radiuses of the vertexes of the reflecting surfaces of the primary mirror and the secondary mirror are respectively-400mm to-360mm and-220mm to-180mm; the axial interval between the primary mirror and the secondary mirror is-140 mm to-120 mm.

The application provides an optical system and an optical lens working in a far-infrared wave band, which sequentially comprises, along an optical axis, from an object side to an image side: a first chalcogenide refractive lens, a superlens, and a second chalcogenide refractive lens; the first chalcogenide refractive lens and the second chalcogenide refractive lens are both positive lenses; the superlens comprises a substrate and a superstructure unit, and the superstructure unit is provided with micro-nano structures; the optical system satisfies the following condition with a unit of 1 / mm: 0.25<=n*(|C1|+|C2|)<=2.01; wherein, when n is the refractive index of the first chalcogenide refractive lens, C1 is the curvature of the front surface of the first chalcogenide refractive lens, and C2 is the curvature of the back surface of the first chalcogenide refractive lens; when n is the refractive index of the second chalcogenide refractive lens, C1 is the curvature of the front surface of the second chalcogenide refractive lens, and C2 is the curvature of the back surface of the second chalcogenide refractive lens. The optical system provided by the application can simultaneously meet the requirements of good imaging quality, small size, sufficient athermalization, and high lens processability of the optical system.

The invention provides a Gamma lens and an industrial camera comprising the Gamma lens, the Gamma lens is an optical imaging system, and the Gamma lens sequentially comprises a first lens to a ninth lens with specific diopters and surface types and a diaphragm from an object side to an image side along an optical axis; by optimizing lens configuration, material matching and optical parameters, the problems of small target surface, easy thermal defocus, small inclination angle, small numerical aperture and the like in the prior art are effectively solved; the lens has the advantages of a large imaging target surface (the diameter of an imaging ring is 22 mm), good athermalization performance (the working temperature range is-20 DEG C to + 60 DEG C), a large object plane inclination angle (larger than 50 degrees), a large numerical aperture (NA = 0.12), a specific working wave band (395-415 nm) and the like, and the imaging quality, the environmental adaptability and the measurement precision in the fields of machine vision, 3D measurement and the like are remarkably improved; the invention also discloses an industrial camera comprising the Sammer lens.

The application provides a high-pixel forward-looking intelligent driving optical system and an applied camera module. The optical system is sequentially composed of a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens. Through reasonable distribution of the surface shape and the optical power of each lens, the volume of the optical system can be effectively reduced, the performance of a large target surface, a large aperture and high pixels is achieved, the optical system has the unique advantages of stable performance, high pixels, a large aperture, a large target surface, no thermalization and no ghost image, and the driving safety of the driver and passengers can be more effectively protected.

The invention provides chalcogenide glass with a negative refractive index temperature coefficient as well as a preparation method and application of the chalcogenide glass, and belongs to the technical field of infrared chalcogenide glass. The chemical formula of the chalcogenide glass provided by the invention is As < x > Se < 100-x >, and x ranges from 20 to 36. By optimizing the chemical formula of the chalcogenide glass, the refractive index and the dn / dT value of the chalcogenide glass can be controlled, and the dn / dT value of the chalcogenide glass is negative, so that the characteristic that the refractive index generated by a conventional lens changes along with the temperature can be effectively compensated, and the heat effect is reduced or even eliminated; the linear refractive index value of the chalcogenide glass provided by the invention is reduced along with the increase of the dn / dT value, so that the chalcogenide glass can be used as a passive athermalization lens element in an infrared system, and is of great significance to athermalization of the system. The result of the embodiment shows that the dn / dT value of the chalcogenide glass provided by the invention is-45 to-19 ppm / K, and the refractive index of the chalcogenide glass is 2.61 to 2.68.

The invention relates to the technical field of optical lenses, in particular to an athermalized ultra-wide-angle lens, which comprises a lens barrel, and a first lens group, a diaphragm and a second lens group which are coaxially arranged in the lens barrel in sequence, from the object side to the image side, the first lens group comprises a first lens, a second lens, a third lens and a fourth lens which are arranged in sequence, and the second lens group comprises a fifth lens, a sixth lens and a seventh lens which are arranged in sequence. Wherein the first lens is a fisheye-type meniscus negative lens, and the concave surface of the first lens faces the image space; the second lens and the third lens are meniscus negative lenses, and the concave surfaces of the second lens and the third lens face the image space. The fourth lens is a positive lens; the fifth lens, the sixth lens and the seventh lens are all positive lenses. The field angle of the lens provided by the invention reaches 185 degrees, and all objects right ahead can be shot comprehensively without dead angles; the aperture value can reach 1.4, and rapid imaging can be realized; and the lens can adapt to an environment with a temperature range of-40 DEG C to 80 DEG C, and covers most of outdoor temperature environments, so that the adaptability of the lens to the environment is effectively improved.

The invention provides an optical antenna structure with a wide temperature adaptation range, which comprises a plurality of optical lenses, each optical lens is sleeved with a gasket, the optical lenses provided with the gaskets are fixed in a lens barrel through a pressing ring, a space ring for separating the optical lenses is further arranged in the lens barrel, and a solar optical filter is arranged at the front end of the lens barrel; the optical lens is made of optical glass with low heat sensitivity, the lens cone is made of an aluminum alloy material, the space ring is made of an invar steel material, the gasket is a graphene gasket subjected to anti-oxidation treatment, and the solar optical filter is made of microcrystalline glass and is coated with an aluminum film. The athermalization design is carried out by selecting an optical structure material with a low thermal expansion coefficient, so that the optical antenna structure can keep stable performance in a larger temperature range, and the possibility of mechanical deformation or rigid body displacement of the optical antenna structure in a space extreme temperature environment is further reduced.

The invention relates to the technical field of cooling optical elements, in particular to a chalcogenide material-based long-wave refrigeration athermalization optical system, which comprises temperature behavior recognition, acquisition of material temperature thickness focus feedback and analysis of a master control behavior sequence, optical path response, extraction of lens actions and generation of a priority sequence, the perturbation effect sequences the lens response according to the deformation frequency, the actuation linkage constructs a synchronous driving path and keeps continuous response, and the focal level drift alignment corrects the lens group according to the image change and stabilizes the performance. Through multi-source feedback parallel analysis, temperature, thickness and focus changes form a traceable chain unified reference, a potential change lens is exposed in advance by comparing lens actions and optical path arrangement, the disturbance degree corresponding to the adjustment syn-position is determined through the displacement frequency, actuation coherence is maintained through path switching, and the adjustment direction is guided through image differences. And the image is kept stable and consistent in dynamic cooling.

The utility model discloses a two-piece optical athermalization lens which comprises a first lens and a second lens which are sequentially arranged from the object side to the image side along the optical axis, the first lens is a meniscus negative lens with the convex face facing the object side, the second lens is a biconvex lens, the focal length of the lens is f, the focal length of the first lens is f1, and the focal length of the second lens is f2, the curvature radius of the intersection point of the object side surface of the first lens and the optical axis is R1, the curvature radius of the intersection point of the image side surface of the first lens and the optical axis is R2, the curvature radius of the intersection point of the object side surface of the second lens and the optical axis is R3, and f, f1, f2, R1, R2 and R3 meet the following relations:-5.6 < f1 / f <-4, 0.6 < f2 / f < 1.2, 1.3 < R1 / R2 < 2.5, and 4.4 < R3 / R1 < 5.4. The athermalization lens can realize the characteristic of temperature self-adaptive optical athermalization, is simple in structure, small in size and light in weight, and can meet the use requirements of a miniaturized uncooled infrared optical system. The utility model further discloses an imaging device.

The application discloses an infrared large-view-field wide-spectrum multi-spectrum imaging spectrometer optical system, which is coaxially arranged in sequence from an object plane to a focal plane as a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a filter wheel; the first lens and the fourth lens are meniscus positive lenses, the second lens, the third lens and the fifth lens are meniscus negative lenses, and the sixth lens is a double-convex positive lens. The application adopts common chalcogenide and zinc selenide crystal infrared materials, corrects aberration and chromatic aberration by optimizing surface shape parameters of each surface and adopting aspheric surfaces, realizes high-quality imaging in a wide waveband range of 2.5-15 mu m, has the characteristics of large view field, small distortion, athermalization and super-long back intercept, is easy to produce and adjust, has strong versatility, and can be applied to the fields of monitoring of chemical harmful gases, environmental protection, agriculture and food safety, medical treatment and health and judicial identification.

The application discloses a compact athermal high-definition wide-angle optical system, which comprises, in sequence from an object side to an image side along an optical axis, a first lens with negative focal power, the object side of which is a convex surface and the image side of which is a concave surface; a second lens with positive focal power, the object side of which is a concave surface and the image side of which is a convex surface; a third lens with positive focal power, the object side of which is a convex surface and the image side of which is a convex surface; a fourth lens with positive focal power, the object side of which is a convex surface and the image side of which is a convex surface; a fifth lens with negative focal power, the object side of which is a concave surface and the image side of which is a convex surface; and an infrared filter, which is located between the fifth lens and an imaging surface; the third lens is a glass spherical lens, the first lens, the second lens, the fourth lens and the fifth lens are plastic aspherical lenses, and a diaphragm is arranged between the second lens and the third lens. The full field modulation transfer function (MTF) is greater than 50% at 100 lp / mm, the maximum field of view is 140°<FOV<156°, the total optical length (TTL) is less than 15.1 mm, and the working waveband is 400-700 nm.

This invention belongs to the field of infrared lens design and manufacturing technology, and relates to a large-aperture 2K resolution infrared lens. The infrared lens, along the light incident direction, sequentially comprises a first lens with negative optical power, a second lens with positive optical power, a third lens with positive optical power, a fourth lens with negative optical power, a detector protective glass, and an imaging target surface for the detector. The first, second, third, and fourth lenses are all convex surfaces in the light incident direction and concave surfaces in the opposite direction. This invention provides a large-aperture 2K resolution infrared lens with a thermal-free design, capable of normal operation within a temperature range of -40℃ to 50℃, and compatible with 1920*1080@8μm uncooled long-wave infrared detectors. It features a large aperture, simple structure, and large imaging target surface size.

The invention provides an athermalization space debris detection optical system. According to the scheme, the field curvature and color are corrected by adopting negative-positive-negative-positive-positive-positive-positive-negative and corresponding refractive index combination according to the focal power of a system lens; besides, the first negative lens adopts negative focal power to increase the relative aperture, SILICA is adopted as a material for radiation resistance, the optical system is prevented from using a radiation-proof flat window, the weight of the optical system is reduced, and the length of the optical system is reduced; moreover, in the temperature range of-10 DEG C to 50 DEG C, the size of optical defocused spots in the full field of view of 14 degrees is balanced, and the system distortion is small.

The invention provides a vehicle-mounted auxiliary driving large-aperture glass-plastic mixed looking-around optical system. The vehicle-mounted auxiliary driving large-aperture glass-plastic mixed looking-around optical system sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens, a seventh lens, an optical filter, protective glass and an image plane from an object plane to an image plane along an optical axis. The 2G5P structure is adopted, the aperture is designed to F1.6, the large aperture structure design is adopted, the imaging definition in the low-illumination environment can be improved, the sentinel function of a vehicle-mounted system is met, the imaging quality requirement for normally monitoring the surrounding conditions of a vehicle in the low-illumination environment is met, meanwhile, the athermalization design is adopted, thermal temperature drift compensation is achieved, and the imaging quality of the vehicle-mounted system is improved. And the working temperature can range from-40 DEG C to 105 DEG C, so that the application of the product in complex temperature scenes is greatly improved.

The application discloses athermal micro-array LED projection lens, which comprises a first lens, a diaphragm, a second lens, a third lens, a fourth lens and a fifth aspherical lens arranged in sequence along a main optical axis from an object side to an image side; the first lens is a biconvex or plano-convex lens with positive focal power; the second lens is a meniscus lens with positive focal power; the third lens is a biconcave or plano-concave lens with negative focal power; the fourth lens is a meniscus or plano-convex lens with positive focal power; and the fifth aspherical lens is a meniscus aspherical lens with positive focal power. The application effectively solves the problem of serious outdoor athermalization, effectively controls the light path through the matching of important parameters such as the surface curvature, the interval and the material characteristics of the lenses, greatly shortens the lens size, reduces the lens cost, effectively controls various aberrations, improves the imaging quality and the thermal stability of the lens.

The utility model discloses a large-relative-aperture athermalization near-infrared optical lens for a Raman spectrum analyzer. The large-relative-aperture athermalization near-infrared optical lens comprises an image plane, a reflecting mirror, a first positive crescent lens, a second positive crescent lens, a third negative crescent lens, a fourth negative crescent lens, a fifth negative crescent lens and a reflecting grating which are sequentially arranged from right to left. Through the above mode, according to the large-relative-aperture athermalization near-infrared optical lens used for the Raman spectrum analyzer, through arrangement and improvement of the lens, the reflecting mirror and the reflecting grating, the large-relative-aperture athermalization near-infrared optical lens is realized, and the athermalization effect is good. The spectral resolution and imaging quality of the lens can be improved in a large temperature range, and the lens is small in size and high in universality.

A chalcogenide material-based low-cost long-wave refrigeration athermalization optical system belongs to the technical field of optical imaging, and is sequentially and coaxially provided with a fairing, a first lens, a second lens, a third lens, detector protection glass, a cold diaphragm and an image plane from outside to inside in a light propagation direction. The optical system is used for receiving inherent infrared radiation passing through a target and a background and converging the infrared radiation to the photosensitive surface of the long-wave infrared refrigeration detector, optical signals are converted into electric signals through photoelectric conversion, and the system has high sensitivity and small spatial resolution and can be used for detecting the target and the background. Detection, identification and accurate positioning of a target can be realized at night or under a complex meteorological condition. The system has the prominent advantages of excellent imaging quality in a working temperature range of-40 DEG C to + 70 DEG C, strong light collecting capability, good environmental adaptability, strong anti-interference capability, capability of working all day long and the like, and can be widely applied to the fields of spaceflight optical remote sensing, optical imaging guidance, astronomical observation, civil safety monitoring and the like.

The present application belongs to the field of aviation / aerospace photoelectric remote sensing imaging detection technology, and particularly relates to a light and small common-aperture infrared / laser ranging integrated camera. During operation, infrared incident light sequentially passes through a first mirror surface, a third mirror surface, a second mirror surface and a beam splitter, and is then reflected onto an infrared receiving assembly. Incident laser light sequentially passes through the first mirror surface, the third mirror surface, the second mirror surface and the beam splitter along an optical path, and is then refracted onto a laser receiving assembly. The material of the annular multi-surface common main mirror, secondary mirror, main mirror barrel and secondary mirror seat is aluminum alloy, which is light in weight, high in strength and easy to process, and is beneficial to the manufacture and adjustment of the device, and is more conducive to the realization of athermalization design. The device still maintains good imaging quality or detection performance under a wide dynamic temperature environment of -150 DEG C to +80 DEG C, greatly reduces the volume of the device, realizes lightweight design of the system, solves the problems of low optical system transmittance and large optical-mechanical structure background radiation at high temperatures, and improves the detection performance of the system.

The lens comprises a first lens, a second lens, a third lens and a fourth lens which are sequentially arranged from the object side to the image side, the focal power of the four lenses is negative-positive-negative-positive, the first lens is a double-meniscus negative lens with the convex face facing the object side, the second lens is a double-meniscus negative lens with the convex face facing the image side, and the fourth lens is a double-meniscus negative lens with the convex face facing the image side. One of the surfaces is an aspheric surface; the second lens is a biconvex positive lens of which the convex surface faces the object side; the third lens is a double-meniscus negative lens of which the convex surface faces the object side, and one surface of the third lens is an aspheric surface; the fourth lens is a double-meniscus positive lens with a convex surface facing the object side, and one surface of the fourth lens is a diffraction surface. According to the invention, a four-piece structure with negative-positive-negative-positive focal power is adopted, and particularly, the negative lens is placed at the foremost part, so that the effective aperture of the first lens can be effectively compressed, the field angle can be enlarged, the rear working distance of the lens can be increased, various aberrations can be corrected, and high-performance passive athermalization of the lens can be realized; and then the design of an aspheric surface, a diffraction surface and the like is coupled, so that the functions of large target surface, high resolution, large relative aperture and wide temperature range imaging clearness can be realized, and the imaging requirement of a large-pixel-scale medium-wave refrigeration detector can be met.

The invention provides a large-target-surface ultra-clear thermal-stability DVR optical imaging lens. The optical imaging lens sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens, a seventh lens, an optical filter, protective glass and an image plane from an object plane to the image plane along an optical axis. According to the invention, a 2G5P structure is adopted, and a 1 / 1.8 inch large-target-surface chip can be matched while the cost is obviously reduced. According to the invention, the aperture is F1.6, so that the night vision photosensitive performance of the recorder is effectively enhanced, and the recorder can still clearly record the driving road condition in a low-light environment. The athermalization design is adopted, effective compensation of thermal temperature drift can be achieved, the working temperature range is wide to-40 DEG C to 85 DEG C, and application requirements of various complex temperature scenes can be met. In the aspect of optical design, the plastic aspheric lens and the glass spherical lens are combined, the lens chromatic aberration is remarkably corrected, and the overall quality of an imaging picture is improved.

The utility model discloses an imaging lens comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens which are sequentially arranged along an optical axis from an object side to an image side. The first lens has a positive refractive index, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a plane; the second lens has a positive refractive index, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; and the like. According to the utility model, the lens adopts six pieces of grinding spherical glass, the light path structure is simple, the assembly is facilitated, and the light assembly yield is high; the light transmission FNO of the lens reaches 2.0, the imaging is excellent, no obvious purple edge and chromatic dispersion exist, the image quality is clear and bright, the lens can adapt to a target surface with two millions of pixels, and the pixel size is 2 microns; the wavelength range of the lens is 435-650 [mu] m; application requirements of special scenes are met, and all-weather clear imaging requirements are covered; the lens meets the temperature drift requirement from-40 DEG C to 85 DEG C, and athermalization design is achieved.

This application discloses an optical system including a short-focal-length eyepiece and a display adapted to the eyepiece. The short-focal-length eyepiece has a focal length of 13.7 mm, a field of view of 40°, a magnification of 18x, an exit pupil diameter of 8 mm, an exit pupil distance of 20 mm, an operating temperature range of -40℃ to +60℃, and an operating wavelength range of 0.48 to 0.65 μm. The display is an OLED display with a resolution of 1024×768 and a pixel size of 7.8 μm. The short-focal-length eyepiece consists of a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis from the eye side to the image side. The first and second lenses are cemented together, and the fourth and fifth lenses are cemented together. This short-focal-length eyepiece can achieve clear imaging of a large target area, meets the requirements of low distortion, and adopts a non-thermal compensation method, exhibiting good imaging performance at different operating temperatures.

The invention discloses a fixed-focus wide-angle lens, and the lens sequentially comprises a first lens with negative refractive power from an object side to an image side along an optical axis, a second lens with negative refractive power, a third lens with negative refractive power, a fourth lens with negative refractive power and a fifth lens with negative refractive power, the object side surface of the second lens is a concave surface, and the image side surface of the second lens is a convex surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a convex surface; the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a convex surface; wherein the fourth lens is a glass spherical mirror, the other lenses are plastic aspherical mirrors, and a diaphragm is arranged between the second lens and the third lens. The system has the advantages of large field of view, athermalization, high resolution, small size, low distortion and the like.