CN118191982A - Super-surface lens, manufacturing method and infrared folded super-mixed quantum dot camera - Google Patents
Super-surface lens, manufacturing method and infrared folded super-mixed quantum dot camera Download PDFInfo
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Abstract
The invention discloses a super-surface lens, a manufacturing method and an infrared folded super-mixed quantum dot camera, which belong to the technical field of infrared imaging and micro-nano photonics, and comprise a lens, a super-surface lens, a quantum dot infrared detector and an optical lens assembly which are sequentially arranged along an optical axis; the super-surface lens adopts a bonding process, so that the thickness of the super-surface and the mechanical stress which can be born by the super-surface lens are improved. The invention adopts a double-plate type simple optical structure, realizes the simplification of an optical system, has wide application range, ensures the imaging quality of the optical system in an infrared band, and combines the optical system with a quantum dot infrared detector to form an infrared quantum dot camera.
Description
Technical Field
The invention belongs to the technical field of infrared imaging and micro-nano photonics, and particularly relates to a super-surface lens, a manufacturing method and an infrared folded super-mixed quantum dot camera.
Background
Infrared imaging techniques aim to capture thermal radiation information of a target object by an infrared detector and convert it into a visible image. The technology is widely applied to tasks such as night investigation, infrared guidance, missile early warning and the like in the military field, and simultaneously has wide application prospects in the fields such as security monitoring, vehicle-mounted night vision, industrial detection and the like in the civil field. Compared with the traditional infrared detector, the quantum dot detector has the advantages of long service life of effective carriers, low dark current, high working temperature, response to vertical incidence light and the like, and can better identify and detect a target object.
In recent years, with the gradual increase of the application of infrared imaging technology on various mobile devices such as an onboard mobile device and a vehicle-mounted mobile device, the requirements on light weight, simple structure, small size and cost economy of the devices are higher and higher, and a light, compact, simple and practical infrared optical system is becoming an important point of research. In general, the current development trend of infrared imaging technology can be summarized into a simpler system structure and stronger perceptibility.
However, the conventional lens has difficulty in further reducing the weight, volume and cost of the infrared camera because it relies on the curved shape of the element and the optical characteristics of the material to achieve the modulation of the wavefront. Under the background, the super surface is taken as an emerging research direction in the field of nano photonics, and is hopeful to replace a traditional lens, so that the aim of simplifying an infrared optical system is fulfilled. The structure of the super surface is a two-dimensional periodic array of electromagnetic resonance units with sub-wavelength or wavelength scale, which can regulate and control the parameters of intensity, phase, polarization and the like of electromagnetic waves in the whole electromagnetic spectrum range. Compared with the traditional optical element, the imaging technology based on the super surface, in particular to the super surface lens, has the advantages of simple integral structure, economic mass production cost, suitability for plane processing technology and the like, and therefore, the imaging technology has wide application prospect in infrared imaging. The introduction of a super surface lens is expected to further reduce the weight, volume and cost of the infrared camera.
However, at present, the problem of insufficient lens thickness exists in the practical application of the large-caliber super-surface lens, for example, chinese patent CN113917578a discloses a large-caliber chromatic aberration correction super-lens, a super-lens system and an optical system, wherein the super-lens has a larger caliber, but the thickness is insufficient and is less than 2mm, which results in the problems of weakening the optical system structure, reduced shock resistance, easy deformation and distortion, etc.
Disclosure of Invention
Aiming at the defects or improvement demands of the prior art, the invention provides a super-surface lens, a manufacturing method and an infrared folded super-mixed quantum dot camera, thereby realizing the technical problems of light equipment, simple structure, small size, cost economy and insufficient lens thickness of the large-caliber super-surface lens in practical application of the existing infrared quantum dot camera.
In order to achieve the above object, according to one aspect of the present invention, there is provided a method for manufacturing a super surface lens, using a bonding process to increase the thickness of the super surface lens and to decrease the diameter-thickness ratio, thereby increasing the mechanical stress that the super surface lens can withstand, comprising the steps of:
preparing a micro-nano structure array and a bonding alignment mark on the front surface of a first wafer, and coating a film on the front surface to protect the micro-nano structure array; preparing a bonding alignment mark on the front surface of the second wafer, preparing a micro-nano structure array on the back surface, and coating a film on the back surface to protect the micro-nano structure array;
Determining the thickness of a third wafer according to the aperture and transmittance requirements of the super-surface lens, and polishing the front and back surfaces of the third wafer;
and cleaning and heating the first to third wafers, aligning the back surface of the first wafer and the front surface of the second wafer with the third wafer by photoetching, performing heating pre-bonding and high-temperature annealing treatment, and finally cleaning the bonded wafers to remove surface masks.
Optionally, acetone, ethanol and other organic cleaning agents are sequentially used for carrying out vibration cleaning on the wafer, then hydrofluoric acid and other corrosive cleaning agents are used for cleaning the wafer to remove the surface oxide layer, then the wafer is subjected to heating treatment, ammonia water, hydrogen peroxide and other alkaline oxidation solutions are used for treating the wafer, the number of hydroxyl groups adsorbed on the silicon wafer is increased, the bonding effect is improved, and photoetching alignment and wafer bonding are carried out.
In a second aspect, the present invention provides a super-surface lens obtained by the above-described manufacturing method.
The third aspect of the invention provides an infrared folded super-mixed quantum dot camera, which comprises a lens, a super-surface lens, a quantum dot infrared detector and an optical lens assembly which are sequentially arranged along an optical axis;
The lens and the super-surface lens form an optical lens group, the lens is used for converging incident light, and the converged incident light is focused on a focal plane of the quantum dot infrared detector after aberration correction by the super-surface lens;
the quantum dot infrared detector is used for eliminating stray light and incident light of a non-target wave band and carrying out infrared detection imaging;
The lens and the super surface lens are disposed in an optical lens assembly for securing and protecting the lens and the super surface lens.
Optionally, the lens is an aspherical lens, including: a first aspheric surface and a second aspheric surface; the surface coordinates Z 1、Z2 of the first aspheric surface and the second aspheric surface respectively satisfy:
Wherein r is the distance from any point on the aspheric lens to the optical axis of the optical imaging system; c 1、C2 is the curvature of the two corresponding spherical surfaces respectively; k 1、k2 is the cone coefficient of two corresponding spherical surface profile, X 1、Y1、M1、N1 is the fourth term, sixth term, eighth term and tenth term coefficient of the first aspheric surface type coordinate, and X 2、Y2、M2、N2 is the fourth term, sixth term, eighth term and tenth term coefficient of the second aspheric surface type coordinate.
Optionally, the lens is a meniscus refractive lens having positive optical power.
The super-surface lens comprises a dielectric substrate layer and a columnar microstructure array, wherein the columnar microstructure array is formed by arranging a plurality of columnar microstructure units according to a hexagonal lattice or tetragonal lattice periodic array; the columnar microstructure units are all the same in height and are on the order of the wavelength of the thermal radiation of the target object, and the diameters of the columnar microstructure units are on the order of sub-wavelength.
The quantum dot infrared detector comprises a detector window sheet, a filter and an infrared photosensitive surface, wherein the detector window and the infrared photosensitive surface are sequentially arranged along the optical axis direction; the detector window sheet and the filter sheet are used for eliminating stray light and incident light of non-target wave bands; the infrared photosensitive surface is used for detecting and imaging the focused light.
The lens and the super-surface lens are arranged on the optical lens assembly, and the optical lens assembly adopts a thread and groove structure to fix and protect the lens and the super-surface lens and is convenient for the structural adjustment of an optical system.
The optical lens assembly comprises a lens barrel main body and a lens barrel outer wall, wherein a buffer rubber material is arranged at a groove structure arranged in the lens barrel main body and used for damping and protecting an optical system, and the lens barrel outer wall is provided with a heat insulation material coating.
Phase distribution of the periodic array of columnar microstructure unitsThe following expression is satisfied:
wherein ρ is the super surface radial coordinate, R is the normalized radius, n is the maximum term of the phase distribution, and a i (i=1, 2,3, … n) are polynomial coefficients.
Alternatively, the radius and height of the columnar microstructure elements at each location on the super-surface lens are determined from the phase distribution of a hexagonal or tetragonal lattice periodic array.
Optionally, both the front and back surfaces of the super-surface lens are plated with anti-reflection and anti-reflection film layers for anti-reflection of incident light and filtering of incident light in non-target wave bands.
Optionally, the super-surface lens is a double-sided super-surface lens or a single-sided super-surface lens.
Optionally, the columnar microstructure unit material includes but is not limited to silicon, germanium or titanium dioxide; the material of the dielectric substrate layer includes, but is not limited to, silicon dioxide, or barium fluoride.
Alternatively, the super surface lens is fabricated using a semiconductor process, including but not limited to ICP etching, photolithography, nanoimprinting.
Optionally, the super surface lens adopts a bonding process to increase the thickness of the super surface lens and reduce the diameter-thickness ratio, thereby improving the mechanical stress that the super surface lens can bear, and the wafer bonding process comprises the following steps:
By the above technical scheme, compared with the prior art, the invention can obtain the following
The beneficial effects are that:
1. The invention provides a manufacturing method of a super-surface lens, wherein the super-surface lens can be manufactured through a multi-piece bonding process, the thickness of a third wafer can be selected according to actual requirements, the thickness of a lens is increased, the radius-thickness ratio is reduced to be below 10, and therefore the mechanical stress which the super-surface lens can bear, the structural strength and the shock resistance of the super-surface lens are improved, and the overall stability of an optical system is improved on the premise that the optical performance of the system is not influenced; meanwhile, the super-surface lens is prepared by adopting a semiconductor process, so that mass production can be realized, the optical processing precision and reliability are improved, and the mass production cost of an optical system is reduced.
2. In the prior art, the color difference correction superlens can be provided, the aperture of the superlens is larger, but the thickness is insufficient, so that the problems of weakening the structure of an optical system, reducing the shock resistance, easily generating deformation, twisting and the like are caused.
3. The infrared folded super-mixed quantum dot camera provided by the invention has the advantages that the optical lens part only adopts a double-sheet structure, the system structure is simple, the assembly is easy, and the number of sheets is reduced compared with the traditional optical system; meanwhile, the optical performance of the system is excellent, the Modulation Transfer Function (MTF) is close to the diffraction limit, the combination with the small-pixel and large-array quantum dot infrared detectors is realized by utilizing a simple lens structure, the high-resolution infrared detection imaging is realized, and the imaging quality is good; the optical lens assembly adopts a screw thread and groove structure to fix and protect the lens and the super-surface lens, and is convenient for the structural adjustment of an optical system.
Drawings
Fig. 1 is a schematic structural diagram of an infrared folded super-hybrid quantum dot camera according to an embodiment of the present invention.
Fig. 2 is a schematic structural diagram of a super-surface lens according to an embodiment of the present invention.
Fig. 3 is a graph of MTF for a simulated first optical system in accordance with an embodiment of the present invention.
Fig. 4 is a spot-plot of a simulated mid-infrared quantum dot detector at the photosurface in accordance with an embodiment of the invention.
Fig. 5 is a graph of MTF for a simulated second optical system according to an embodiment of the present invention.
FIG. 6 is a spot-plot of a simulated near infrared quantum dot detector at the photosurface in accordance with an embodiment of the invention.
Fig. 7 is a schematic flow chart of a super surface lens bonding process according to an embodiment of the invention.
The same reference numbers are used throughout the drawings to reference like elements or structures, wherein: 1-a lens; 2-a super surface lens; 3-quantum dot infrared detector; 4-optical lens assembly.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. In addition, the technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
The electromagnetic super-surface structure is a two-dimensional periodic array of electromagnetic resonance units with sub-wavelength or wavelength scale, and the electromagnetic super-surface structure has the function of regulating and controlling the parameters such as the intensity, the frequency, the phase, the polarization and the like of electromagnetic waves in the whole electromagnetic spectrum range. Compared with the traditional optical element, the imaging technology based on the electromagnetic super-surface, in particular to the super-surface lens, has the advantages of simple integral structure, low mass production cost, suitability for plane processing technology and the like, and therefore, the imaging technology has wide application prospect in infrared imaging. The introduction of the super-surface lens is expected to further reduce the weight, volume and cost of the infrared camera, and the super-surface lens is combined with the traditional refraction lens, so that a new scheme is provided for the design of an infrared detection system.
The description of the contents of the above embodiment will be given below in connection with a preferred embodiment.
Example 1
As shown in fig. 1, the present invention provides an infrared folded super-hybrid quantum dot camera, comprising a lens 1, a super-surface lens 2, an infrared quantum dot detector 3 and an optical lens assembly 4, which are sequentially arranged along the incident light direction;
the super-surface lens 2 adopts a bonding process to improve the thickness of the super-surface and the mechanical stress thereof;
the quantum dot infrared detector 3 is used for eliminating stray light and incident light of a non-target wave band and performing infrared detection imaging;
the lens 1 and the super-surface lens 2 form an optical lens group, and are used for converging the thermal radiation of a target object and focusing the thermal radiation on the surface of the quantum dot infrared detector 3;
The refractive lens 1 and the super surface lens 2 are arranged on the optical lens assembly 4, and the optical lens assembly 4 adopts a thread and groove structure to fix and protect the lens and the super surface lens and is convenient for the structural adjustment of an optical system.
The super-surface lens 2 comprises a dielectric substrate layer and a columnar microstructure array, as shown in fig. 2, wherein the columnar microstructure array is formed by arranging a plurality of columnar microstructure units according to a hexagonal lattice or tetragonal lattice periodic array; the heights of the columnar microstructure units are all the same and are in the wavelength magnitude of the thermal radiation of the target object, and the diameters of the columnar microstructure units are in the sub-wavelength magnitude;
phase distribution of the periodic array of columnar microstructure units The following expression is satisfied:
wherein ρ is the super surface radial coordinate, R is the normalized radius, n is the maximum term of the phase distribution, and a i (i=1, 2,3, … n) are polynomial coefficients.
Optionally, the diameter, period, height and arrangement of the columnar microstructure units are determined according to the corresponding phase distribution.
The infrared quantum dot detector used in this embodiment is used to image the focused infrared light, and its pixel size is 15 μm, and the number of pixels or resolution is 640×512. When the MTF curve of the optical system approaches the diffraction limit and the cut-off frequency and the pixel spacing of the detector satisfy the formula: cut-off frequency = 1/(2 pixel size), this means that the optical system matches the detector and the optical performance is good.
In a specific embodiment, the infrared folded super-mixed quantum dot camera provided by the invention is used for realizing focusing imaging in a middle infrared band with a 4.25 μm central wavelength and 3.7-4.8 μm, the entrance pupil diameter of an optical system is 32.4mm, the angle of view is 5.4 degrees, the focal length of the system is 63.2mm, the f-number is 2, the total length of the optical system is not more than 64mm, and the focal length change is less than 0.1% in the 3.7-4.8 μm band.
In more detail, the values of specific parameters in the first optical system provided by the embodiment of the invention are shown in table one, table two and table three.
Table one: super surface lens parameter table of first optical system
| R(mm) | A1 | A2 | A3 | A4 | |
| A first super surface | 1 | -25.026 | -0.129 | -7.094E-04 | 2.666E-06 |
| R(mm) | A5 | A6 | A7 | A8 | |
| A first super surface | 1 | 2.737E-08 | 4.834E-11 | -1.958E-12 | 7.849E-15 |
| R(mm) | A9 | A10 | |||
| A first super surface | 1 | 1.923E-16 | -2.087E-18 | ||
| R(mm) | A1 | A2 | A3 | A4 | |
| Second super surface | 1 | 24.984 | 0.148 | 9.205E-04 | -5.782E-06 |
| R(mm) | A5 | A6 | A7 | A8 | |
| Second super surface | 1 | 7.344E-09 | -5.107E-11 | -2.629E-12 | -4.618E-15 |
| R(mm) | A9 | A10 | |||
| Second super surface | 1 | 2.231E-16 | 5.413E-19 |
And (II) table: first optical system structural parameters
Table three: aspherical lens conic coefficient and polynomial coefficient of first optical system
The MTF curve graph of the first optical system of the mid-infrared band infrared folded super-mixed quantum dot camera provided by the embodiment of the invention is shown in fig. 3, the MTF values under all fields are higher than 0.5 at the cut-off frequency of 34lp/mm, the MTF curve is close to the diffraction limit, the system point graph is shown in fig. 4, the RMS radius is smaller than 6 μm, the maximum color focus shift is smaller than 0.1%, and the near diffraction limit imaging is realized.
In another specific embodiment, the infrared folded super-mixed quantum dot camera provided by the invention is used for realizing focusing imaging in a middle infrared band with a central wavelength of 1.55 mu m and a focal length of 1.3-1.8 mu m, the entrance pupil diameter of an optical system is 12mm, the angle of view is 5.4 degrees, the focal length of the system is 46.1mm, the f-number is 4, the total length of the optical system is not more than 42mm, and the focal length change is less than 0.12% in the band of 1.3-1.8 mu m.
In more detail, the values of specific parameters in the second optical system provided by the embodiment of the invention are shown in table four, table five and table six.
Table four: super surface lens parameter table of second optical system
Table five: structural parameters of the second optical system
Table six: aspherical lens conic coefficient and polynomial coefficient of second optical system
The MTF curve graph of the second optical system of the infrared folded super-mixed quantum dot camera in the near infrared band is shown in fig. 5, the MTF values of all the fields are higher than 0.6 at the cut-off frequency of 34lp/mm, the MTF curve is close to the diffraction limit, the system point graph is shown in fig. 6, the RMS radius is smaller than 4.2 microns, the maximum color focus shift is smaller than 0.12%, and the near diffraction limit imaging is realized.
The embodiment of the invention provides an infrared folded super-mixed quantum dot camera, which adopts a mode of mixing a refractive lens and a super-surface lens, wherein the super-surface lens modulates incident light together with the refractive lens by virtue of the fine regulation and control capability of the super-surface lens on the incident light, the optical system performance is excellent, an MTF curve is close to a diffraction limit, and the f-number is matched with a target detector, so that the combination with the infrared quantum dot detector is realized; the super-surface lens manufactured by the design adopts a bonding process, so that the thickness of the super-surface lens is increased, the mechanical stress which the super-surface lens can bear, the structural strength and the shock resistance of the super-surface lens are increased, and the overall stability of the optical system is improved on the premise that the optical performance of the system is not influenced.
Example two
The invention also provides a manufacturing method of the super-surface lens, which comprises the following steps:
The super-surface lens is prepared by a semiconductor process, and the super-surface preparation method comprises the steps of, but is not limited to, ICP etching, photoetching and nanoimprint;
Optionally, the super surface lens adopts a bonding process, and a flow chart is shown in fig. 7, so as to increase the thickness of the super surface lens and reduce the diameter-thickness ratio, thereby improving the mechanical stress that the super surface lens can bear, and the wafer bonding process comprises the following steps:
Firstly, reserving mark positions during photoetching layout drawing, preparing a micro-nano structure array and an alignment mark on the front surface of a first wafer of super-structure elements by utilizing processes such as step-by-step photoetching, deep silicon etching and the like, preparing a bonding alignment mark on the front surface of a second wafer of super-structure elements by utilizing a double-sided photoetching process, and preparing a micro-nano structure array on the back surface of the wafer; and then carrying out surface coating treatment on the super-structure element to protect a microstructure array on the surface of the super-structure element, adopting a surface polished high-purity silicon wafer, determining the thickness of the wafer according to the requirements of the caliber and the transmittance of the super-surface lens, sequentially using acetone and ethanol to carry out vibration cleaning on the silicon wafer in an ultrasonic cleaner, then using hydrofluoric acid to clean the silicon wafer to remove an oxide layer on the surface of a silicon wafer, then putting the silicon wafer into a solution consisting of concentrated sulfuric acid and hydrogen peroxide for heating treatment, treating the silicon wafer with ammonia water and hydrogen peroxide after cleaning, carrying out photoetching alignment by using a photoetching machine after cleaning, carrying out heating pre-bonding and high-temperature annealing treatment in the wafer bonding machine, and finally using a buffer oxide etching liquid to clean the bonded silicon wafer to remove a surface mask.
The number of the specific bonding sheets is determined according to the absorption coefficient of the substrate material in a target wave band, the index requirement of the system transmittance and the ratio of the diameter to the thickness required by the assembly of the super-surface lens.
The super-surface lens manufactured by the manufacturing method of the super-surface lens provided by the embodiment is applied to the infrared folded super-mixed quantum dot camera, and has the corresponding beneficial effects as in the embodiment.
It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the invention and is not intended to limit the invention, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (10)
1. A method of manufacturing a super-surface lens, comprising the steps of:
preparing a micro-nano structure array and a bonding alignment mark on the front surface of a first wafer, and coating a film on the front surface; preparing a bonding alignment mark on the front surface of the second wafer, preparing a micro-nano structure array on the back surface, and coating a film on the back surface;
Determining the thickness of a third wafer according to the aperture and transmittance requirements of the super-surface lens, and polishing the front and back surfaces of the third wafer;
and cleaning and heating the first to third wafers, aligning the back surface of the first wafer and the front surface of the second wafer with the third wafer by photoetching, performing heating pre-bonding and high-temperature annealing treatment, and finally cleaning the bonded wafers to remove surface masks.
2. A super-surface lens, characterized in that it is obtained by the manufacturing method according to claim 1.
3. An infrared folded super hybrid quantum dot camera, characterized by comprising a lens (1), a super surface lens (2) according to claim 2, a quantum dot infrared detector (3) and an optical lens assembly (4) which are arranged in sequence along an optical axis;
The lens (1) is used for converging incident light, and the converged incident light is focused on a focal plane of the quantum dot infrared detector (3) after aberration correction by the super-surface lens (2);
The quantum dot infrared detector (3) is used for eliminating stray light and incident light of a non-target wave band and performing infrared detection imaging;
The lens (1) and the super surface lens (2) are arranged in the optical lens assembly (4), and the optical lens assembly (4) is used for fixing and protecting the lens (1) and the super surface lens (2).
4. An infrared folded super-hybrid quantum dot camera according to claim 1, characterized in that the lens (1) is an aspherical lens or a meniscus refractive lens with positive optical power.
5. An infrared folded super mixed quantum dot camera according to claim 1, wherein the super surface lens (2) comprises a dielectric substrate layer and columnar microstructure arrays located at both sides of the dielectric substrate layer, the columnar microstructure arrays comprising a plurality of columnar microstructure units arranged in a hexagonal lattice or tetragonal lattice periodic array; the height of each columnar microstructure unit is the same and is in the wavelength magnitude of the thermal radiation of the target object, and the diameter and the period of each columnar microstructure unit are in the sub-wavelength magnitude;
phase distribution of the periodic array of columnar microstructure units The following expression is satisfied:
Wherein ρ is the super surface radial coordinate, R is the normalized radius, n is the maximum number of terms of phase distribution, a i is the polynomial coefficient, i=1, 2,3, … n.
6. An infrared folded super mixed quantum dot camera according to claim 5, characterized in that the super surface lens (2) is designed by the following method:
the simulation obtaining of the corresponding relation between the size of the columnar microstructure unit in the super-surface lens, the phase distribution and the transmittance comprises the following steps:
According to a time domain finite difference algorithm and a strict coupled wave analysis method, the size parameters of the columnar microstructure units of the super-surface lens are simulated, and the corresponding relation among the heights, the periods and the diameters of the columnar microstructure units, the phase distribution and the transmittance is determined.
7. An infrared folded super mixed quantum dot camera as claimed in claim 3, wherein both the front and back surfaces of the super surface lens (2) are plated with anti-reflection film layers of a target wave band.
8. The infrared folded super mixed quantum dot camera according to claim 5, wherein the columnar microstructure unit of the super surface lens (2) is made of silicon, germanium or titanium dioxide; the dielectric substrate layer is made of silicon, silicon dioxide or barium fluoride.
9. An infrared folded super hybrid quantum dot camera according to claim 3, wherein the quantum dot infrared detector (3) comprises a detector window sheet, an optical filter, a diaphragm and an infrared photosensitive surface which are sequentially arranged along the optical axis direction, wherein the detector window sheet, the optical filter and the diaphragm are used for eliminating stray light and incident light of non-target wave bands; the infrared photosensitive surface is used for detecting and imaging the focused light.
10. An infrared folded super hybrid quantum dot camera according to claim 3, wherein the optical lens assembly (4) comprises a lens barrel body and a lens barrel outer wall, a groove structure is arranged in the lens barrel body and used for fixing the lens (1) and the super surface lens (2), and a damping material is arranged at the groove structure and used for damping and protecting the lens (1) and the super surface lens (2); the outer wall of the lens barrel is provided with a heat insulation material coating.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410475129.1A CN118191982A (en) | 2024-04-19 | 2024-04-19 | Super-surface lens, manufacturing method and infrared folded super-mixed quantum dot camera |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410475129.1A CN118191982A (en) | 2024-04-19 | 2024-04-19 | Super-surface lens, manufacturing method and infrared folded super-mixed quantum dot camera |
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| CN118191982A true CN118191982A (en) | 2024-06-14 |
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| CN202410475129.1A Pending CN118191982A (en) | 2024-04-19 | 2024-04-19 | Super-surface lens, manufacturing method and infrared folded super-mixed quantum dot camera |
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| Country | Link |
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| CN (1) | CN118191982A (en) |
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