阅读说明：本技术 双直区弯曲形光学纤维锥及其应用 (Double-straight-area curved optical fiber cone and application thereof ) 是由 黄永刚 付杨 周游 王云 王久旺 焦朋 蔡京生 王叶 于 2020-06-18 设计创作，主要内容包括：本发明的主要目的在于提供一种双直区弯曲形光学纤维锥及其应用。所述光学纤维锥包括大端和小端,组成所述大端的各根光纤平行设置形成大端直区；组成所述小端的各根光纤平行设置形成小端直区；所述大端直区的中心轴与所述小端直区的中心轴不在一条直线上。所要解决的技术问题是通过双直区弯曲形+端面立体结构的设计,使光锥入射到CCD的光线自动聚集,避免发散,减少光纤之间光线的串扰,抑制分辨率的下降,提高了光锥与CCD耦合的效率、光透过率和分辨率,提升了耦合的成像质量,同时又减少了对耦合器件的辐射伤害,提高了器件的耐辐照性能,促进了数字化微光成像、粒子探测技术的进步,从而更加适于实用。(The invention mainly aims to provide a double-straight-area curved optical fiber cone and application thereof. The optical fiber cone comprises a large end and a small end, and all optical fibers forming the large end are arranged in parallel to form a large end straight area; all the optical fibers forming the small end are arranged in parallel to form a small end straight area; the central axis of the large end straight area and the central axis of the small end straight area are not on the same straight line. The technical problem that solve is through the design of two straight district bending types + terminal surface spatial structure, make the light cone incide CCD's light automatic gathering, avoid dispersing, reduce the crosstalk of light between the optic fibre, restrain the decline of resolution ratio, the efficiency of light cone and CCD coupling has been improved, light transmissivity and resolution ratio, the imaging quality of coupling has been promoted, the radiation damage to coupling device has been reduced again simultaneously, the radiation resistance ability of device has been improved, digital shimmer formation of image has been promoted, particle detection technology's progress, thereby be suitable for the practicality more.)

1. A double straight region bending optical fiber cone comprises a big end and a small end, and is characterized in that all optical fibers forming the big end are arranged in parallel to form a big end straight region; all the optical fibers forming the small end are arranged in parallel to form a small end straight area; the central axis of the large end straight area and the central axis of the small end straight area are not on the same straight line.

2. The optical fiber taper of claim 1, wherein a central axis of the large end straight region and a central axis of the small end straight region are parallel or intersect to form an included angle α, wherein 0 ° < α <180 °.

3. The optical fiber taper of claim 1, wherein the large end straight section and the small end straight section each have a length dimension in the axial direction of the optical fiber of greater than 2.0 mm; or the core diameter d of the optical fiber forming the large end is more than or equal to 2 mu m.

4. The optical fiber taper according to claim 1, wherein the cross-section of the large end and the small end is circular, wherein the diameter D of the large end is Φ 10mm to Φ 200 mm; or the sections of the large end and the small end are square, wherein the side length L of the large end is 7-150 mm.

5. The optical fiber taper of claim 1, wherein the length L of the optical fiber taper along the fiber axis direction is greater than or equal to 0.8D, where D is the diameter of the large end or the equivalent diameter of the large end.

6. The optical fiber taper according to any one of claims 1 to 5, wherein the optical fiber comprises a core layer and a skin layer, wherein the skin layer extends beyond the core layer at the end of the optical fiber to make the end surface of the core layer in a concave spherical structure; or the core layer exceeds the skin layer to enable the end face of the core layer to be in a convex spherical structure; the curvature radius R of the concave spherical structure or the convex spherical structure is more than or equal to 0.5d, the arch height h of the concave spherical structure or the convex spherical structure is less than or equal to 0.5d, and d is the core diameter of the optical fiber in the large-end straight region or the small-end straight region.

7. The optical fiber taper of claim 6, wherein the end faces of the core layer comprise an input end face and an output end face; the output end face is of a spherical crown structure; and/or the input end surface is of a spherical cap structure.

8. Use of an optical fiber taper according to claims 1 to 7.

9. Use of an optical fiber taper according to claims 1 to 7 in the field of particle detection.

10. Use of an optical fiber taper according to claims 1 to 7 in the field of low-light night vision imaging.

Technical Field

The invention belongs to the technical field of optical devices, and particularly relates to a double-straight-region curved optical fiber cone with a special structure and application thereof.

Background

An optical fiber taper (hereinafter referred to as a light taper) is an optical device made of a large number of optical fibers through processes of regular arrangement, heating, pressure fusion and stretching; since the light cone has an effect of enlarging and reducing an image by a certain factor and can obtain a small object distance, it becomes one of core elements of an image enhancement device and is widely used in a miniaturized image apparatus and an image digitizing apparatus.

Besides the above-mentioned enlarging and reducing imaging, another key function of the light cone is to couple the light cone with the CCD for converting the image into a digital signal through coupling, so as to implement the image processing and long-distance transmission. However, when the light cone is coupled with the CCD in the prior art, on one hand, the coupling efficiency is low, the coupling resolution is poor, and the imaging definition is poor; on the other hand, it is difficult to achieve different axial couplings of the optical image-transmitting elements. Meanwhile, in the prior art, the radiation-resistant cerium oxide material is introduced into the glass material to absorb the radiation valence change mechanism so as to achieve the radiation-resistant effect. However, this method also has a negative effect, and the use of cerium oxide reduces the light transmittance of the glass itself. Secondly, the radiation-resistant effect is still not ideal enough, and a large amount of high-energy rays still penetrate through the semiconductor device of the component to reach the rear end, so that radiation damage is caused.

Disclosure of Invention

The invention mainly aims to provide a double-straight-area bent optical fiber cone and application thereof, and aims to solve the technical problems of realizing non-coaxial coupling of optical image transmission elements, reducing radiation damage of high-energy rays to a coupling device, improving the coupled imaging quality, promoting the progress of digital low-light-level imaging and particle detection technologies and being more practical.

The purpose of the invention and the technical problem to be solved are realized by adopting the following technical scheme. According to the double-straight-region curved optical fiber cone provided by the invention, the double-straight-region curved optical fiber cone comprises a large end and a small end, wherein all optical fibers forming the large end are arranged in parallel to form a large-end straight region; all the optical fibers forming the small end are arranged in parallel to form a small end straight area; the central axis of the large end straight area and the central axis of the small end straight area are not on the same straight line.

The object of the present invention and the technical problems solved thereby can be further achieved by the following technical measures.

Preferably, the optical fiber taper is described above, wherein the central axis of the large end straight section and the central axis of the small end straight section are parallel or intersect to form an included angle α, wherein 0 ° < α <180 °.

Preferably, the optical fiber taper is provided, wherein the length dimension of each of the large end straight region and the small end straight region along the axial direction of the optical fiber is greater than 2.0 mm; or the core diameter d of the optical fiber forming the large end is more than or equal to 2 mu m.

Preferably, the section of the large end and the small end of the optical fiber taper is circular, and the diameter D of the large end ranges from Φ 10mm to Φ 200 mm; or the sections of the large end and the small end are square, wherein the side length L of the large end is 7-150 mm.

Preferably, the length L of the optical fiber taper along the axial direction of the optical fiber is greater than or equal to 0.8D, wherein D is the diameter of the large end or the equivalent diameter of the large end.

Preferably, the optical fiber taper described above, wherein the optical fiber is composed of a core layer and a skin layer; at the end part of the optical fiber, the skin layer exceeds the core layer so that the end surface of the core layer is in a concave spherical structure; or the core layer exceeds the skin layer to enable the end face of the core layer to be in a convex spherical structure; the curvature radius R of the concave spherical structure or the convex spherical structure is more than or equal to 0.5d, the arch height h of the concave spherical structure or the convex spherical structure is less than or equal to 0.5d, and d is the core diameter of the optical fiber in the large-end straight region or the small-end straight region.

Preferably, the optical fiber taper described above, wherein the end faces of the core layer comprise an input end face and an output end face; the output end face is of a spherical crown structure; and/or the input end surface is of a spherical cap structure.

The purpose of the invention and the technical problem to be solved are realized by adopting the following technical scheme. According to the invention, an application of the optical fiber taper according to the above is provided.

The purpose of the invention and the technical problem to be solved are realized by adopting the following technical scheme. The invention provides the application of the optical fiber cone in the field of particle detection.

The purpose of the invention and the technical problem to be solved are realized by adopting the following technical scheme. The invention provides an application of the optical fiber cone in the field of low-light night vision imaging.

By the technical scheme, the double-straight-region curved optical fiber cone and the application thereof provided by the invention at least have the following advantages:

1. the input end face and/or the output end face of each optical fiber forming the optical fiber cone are of a concave spherical structure or a convex spherical structure, wherein the core layer and the skin layer of each optical fiber are positioned on different planes, and the input end face is designed into the structure, so that incident light of each optical fiber can obtain incident light beams with larger angles, and the light collection capability of each optical fiber can be improved, the light transmittance can be improved, the mutual crosstalk among the light beams can be effectively reduced, and the imaging resolution can be improved; the input end face is designed to be of such a structure that the emergent light of each optical fiber is focused towards the center of each optical fiber; for the whole output surface of the whole optical fiber cone, the purpose of condensing emergent light is realized, light spots of the optical fiber cone are reduced when the optical fiber cone is coupled with a CCD, and the purpose of improving the resolution of the optical fiber cone can be achieved; therefore, the optical fiber cone can converge more incident light rays to enter the light cone, and the light rays transmitted in the light cone have the functions of light convergence and divergence when being output, so that the high resolution, the high light transmittance and the high coupling efficiency of the optical fiber cone and the CCD can be realized;

2. the structure of the double-straight-area bent optical fiber cone is designed into the optical fiber cone with the bent and double-straight-area structures, and the straight area and the three-dimensional structure are combined and applied, so that incident light is converged on the input end face, emergent light is converged on the output end face, the problems of beam divergence of the output end face and inclination of the output end face of the optical cone are solved, the light incident to a CCD by the optical cone is automatically converged, the divergence is avoided, the crosstalk of the light among optical fibers is reduced, the reduction of resolution is inhibited, the coupling efficiency, the light transmittance and the resolution of the optical cone and the CCD are improved, and the coupled imaging quality is improved, so that the coupling efficiency can be adjusted when the optical cone is coupled with other optical fiber image transmission elements such as CCD/CMOS and the like;

3. according to the double-straight-region curved optical fiber cone and the application thereof, through the curved design of the light cone, the light cone can be prevented from being directly irradiated by rays, so that the irradiation resistance of a device can be improved, the irradiation damage to detection elements such as a CCD/CMOS and the like in a high-energy ray use environment can be effectively reduced, and the improvement of digital low-light-level imaging and particle detection technologies is promoted.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to implement them in accordance with the contents of the description, the following detailed description is given with reference to the preferred embodiments of the present invention and the accompanying drawings.

Drawings

FIG. 1 is a schematic diagram of the structure and operation of the light cone of the present invention;

fig. 2 is a schematic diagram of the light cone structure of the present invention, where α is 0 °;

FIG. 3 is a schematic view of the structure of a light cone of the present invention, with 0 < alpha < 90;

fig. 4 is a schematic view of the light cone structure of the present invention, where α is 90 °;

FIG. 5 is a schematic view of a light cone structure of the present invention, 180 > α > 90;

FIG. 6 is a schematic view of the focusing of light in one optical fiber at the output end of the cone of the present invention;

FIG. 7 is a schematic diagram of the light transmission principle of the light cone of the present invention-including the input and output ends of the optical fibers;

FIG. 8 is a schematic view of the light collection in one optical fiber at the input end of the light cone of the present invention.

Detailed Description

To further illustrate the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description will be made on a dual straight section curved optical fiber taper and its application, embodiments, structures, features and effects thereof according to the present invention with reference to the accompanying drawings and preferred embodiments.

The invention provides a double-straight-region curved optical fiber cone, which comprises a large end and a small end, wherein as shown in figure 1, all optical fibers forming the large end are arranged in parallel to form a large-end straight region 1; all the optical fibers forming the small end are arranged in parallel to form a small end straight area 2; the central axis of the large end straight area 1 and the central axis of the small end straight area 2 are not on the same straight line.

The optical fiber cone sequentially comprises a large-end straight area 1, a transition part and a small-end straight area 2, wherein a plurality of optical fibers 21 forming the optical fiber cone extend to the small-end straight area 2 from the large-end straight area 1 and the transition part; the image A to be transmitted passes through the large end straight region 1, the transition part and the small end straight region 2 and then is output as an image A' reduced by several times by the small end.

The end face of the optical fiber 21 forming the large end straight region 1 and the small end straight region 2 is in a non-planar structure; the optical fiber consists of a core layer and a skin layer, wherein the skin layer extends out of the core layer at the end part of the optical fiber to enable the end surface of the core layer to be in a concave spherical structure (the structure is not shown in the attached figure 1); alternatively, the core layer extends beyond the skin layer to make the end surface of the core layer in a convex spherical structure 22.

As shown in the right part of the drawing 1, which is an enlarged view of the small end straight region 2, it can be seen from the enlarged view that the optical fibers 21 constituting the small end straight region 2 are arranged in parallel with each other, a convex spherical structure 22 is arranged on the output end face thereof, the light transmitted by the light cone is reflected by the optical fibers for a plurality of times and then is emitted from the output end face, and the emitted light 3 is incident in a convergent manner into the CCD/CMOS 4 coupled therewith.

Preferably, the end faces of the core layer comprise an input end face and an output end face; the output end face is of a spherical crown structure; and/or the input end face is of a spherical crown structure; the curvature radius R of the spherical crown structure is more than or equal to 0.5d, the arch height h of the spherical crown structure is less than or equal to 0.5d, and the sizes of the curvature radius and the arch height of the end surface spherical crown structure of the large-end straight area are related to the core diameter of the large-end straight area; the curvature radius and the arch height of the end face spherical cap structure of the small end straight area are related to the core diameter of the small end straight area.

Preferably, the arch height of the spherical cap structure is smaller than or equal to the radius of the core layer; the radius of curvature of the spherical cap structure is greater than or equal to the radius of the core layer; the maximum size of the outward protrusion or inward recess of the spherical cap structure does not exceed the size of a half spherical surface taking the radius of the core layer as the radius.

The optical fiber cone of the invention is used as an intermediate image transmission medium, the front surface of the optical fiber cone is connected with an optical fiber panel or fluorescent powder is directly coated on the input end surface of the optical fiber cone, and the back surface of the optical fiber cone is coupled with other optical elements. In order to improve the coupled image quality, particularly the resolution and light transmission performance, the end surface of the core layer and the end surface of the skin layer of each optical fiber on the output end surface and/or the input end surface of the optical fiber cone are not in the same plane, so that the end surface of the core layer forms a convex spherical structure or a concave spherical structure relative to the end surface of the skin layer, the concave spherical structure/the convex spherical structure is in one-to-one correspondence with the core layers of the optical fibers, and the shape and the size of the concave spherical structure are completely matched with those of the core layers.

When the optical fiber is produced, the end face of the optical fiber can be firstly manufactured into a planar structure with the core layer end face and the skin layer end face positioned in the same plane, and then the core layer end face is processed through the subsequent procedures to form a convex spherical structure or a concave spherical structure. Preferably, the convex spherical structure is prepared by combining a chemical difference acid etching method with a heat treatment method; or the convex spherical structure is processed and prepared by a photomask ion etching technology; the concave spherical structure is processed and prepared by a chemical wet acid etching method.

The structure of the end face can be directly processed and manufactured on the optical fiber end head; alternatively, other materials may be used to attach the ends of the optical fibers to form the endface structure. When other materials are used to connect the light ends, the refractive index of the material of the end is preferably the same as or similar to that of the core glass, so as to ensure that the light is transmitted therein without being affected by the change of the material.

The end face of the concave spherical structure/convex spherical structure of the core layer has the curvature radius of R, the arch height of h, the core diameter of straight areas at two ends of the optical fiber cone of d, and the refractive index of the optical fiber core layer glass of n₁Refractive index n of material having end face structure, and refractive index n of medium₀The parameters of the spherical crown structure of the output end face and the input end face of the optical fiber cone core layer can be designed according to the requirements of practical application, the main basis of the design of the spherical crown structure parameters of the input end face is determined according to the size of a target light collection angle β of the optical fiber cone, and after the target light collection angle β is determined, the curvature radius R, the arch height h, the optical fiber core diameter d and the core glass refractive index n of the spherical crown structure are further determined₁Refractive index n of micro-convex structure and refractive index n of medium₀The structure design can lead the incident light of each optical fiber to obtain incident light beams with larger angles, improve the light collection capability of the incident light, improve the light transmittance, effectively reduce the mutual crosstalk among the light beams and contribute to improving the imaging resolution.

Further, key index parameters such as an emergence angle of the light beam, a distance between the output end face and an imaging focal point (focal plane) and the like can be calculated according to the parameters of the spherical cap structure. Based on the acquisition of parameters, the method not only can guide the forming of the spherical crown structure, but also can guide the assembly distance between the optical fiber cone and the coupling element or the thickness of the optical adhesive coating, and the focal plane coincides with the image plane to obtain the best imaging quality.

According to the technical scheme, the output end face of each optical fiber is designed into a spherical crown structure, so that emergent light can be gathered towards the center of each optical fiber; for the whole output surface of the whole optical fiber cone, the purpose of condensing emergent light is realized, so that light spots of the optical fiber cone are reduced when the optical fiber cone is coupled with a CCD (charge coupled device), and the purpose of improving the resolution of the optical fiber cone can be achieved.

Preferably, the central axis of the large end straight region 1 and the central axis of the small end straight region 2 are parallel or intersect to form an included angle α, wherein 0 ° < α <180 °. The central axes of the two ends of the optical fiber cone are not on the same straight line, are either parallel or intersect, and the angle alpha can be between 0 and 180 degrees, and corresponding design can be carried out according to the actual application requirement; the transition part connecting the large end straight area and the small end straight area is bent, that is, two ends of the optical fiber cone are designed to be of an optical fiber cone structure with central axes intersecting or even parallel, that is, the structural design of the bent optical fiber cone is similar to the shape of a 'ox horn', and the integral shape of the bent optical fiber cone is defined as the 'ox horn' type optical fiber cone in the application document of the invention. The structure is designed into a bent double-straight-area optical fiber cone structure, the coupling problem among non-coaxial elements can be solved, and meanwhile, the optical fiber cone not only has the function of amplifying or reducing image transmission, but also has the function of transmitting images in various directions, and the transmission angle can be adjusted between 0 and 180 degrees.

As shown in fig. 2 to 5, the two straight regions are curved optical fiber cones with included angles α of 0 ° (i.e., axes are parallel), 0 ° < α < 90 °, α of 90 ° and 180 ° > α > 90 °, respectively, wherein the central axes of the large end straight region and the small end straight region of the optical fiber cone of fig. 2 are parallel to each other, and the optical fiber cone is a "ox horn" optical fiber cone for low-light level night vision imaging, and can be used in a scene when images are spliced; the optical fiber cones of fig. 3-5 can be used in the image-turning scene.

Preferably, the length dimension of the large end straight region and the length dimension of the small end straight region along the axial direction of the optical fiber are both larger than 2.0 mm. The large end and the small end of the optical fiber cone are both provided with straight areas with certain lengths, and the lengths of the straight areas are determined according to the size of the optical fiber cone. Typically, the length of the straight region is not less than 2.0mm to ensure that the direction of each optical fiber of the large-end straight region and the small-end straight region can be kept perpendicular to the end face. Generally, the length of the large end straight region is greater than the length of the small end straight region.

Preferably, the cross sections of the large end and the small end are circular, wherein the diameter D of the large end ranges from phi 10mm to phi 200 mm.

Preferably, the cross sections of the large end and the small end are square, wherein the side length L of the large end is 7-150 mm.

Preferably, the cross sections of the large end and the small end can also be designed to be irregular, wherein the irregular cross section of the large end is arranged in a circle with the diameter D ranging from Φ 10mm to Φ 200mm, and can be designed to be any shape such as an ellipse, a diamond, a polygon, a racetrack and the like.

Preferably, the magnification M of the optical fiber cone is 1-5. The optical fiber cone is generally used for amplification of small image signals; the magnification value is calculated by dividing the size of the large end of the optical fiber cone by the size of the small end of the optical fiber cone. The size of the large end and the size of the small end may take their equivalent sizes. The size of the small end can be obtained by calculation according to the design value of the magnification value of the optical fiber cone and the effective size of the large end. Preferably, the magnification M of the optical fiber cone is 1-2, 2-3, 3-4 or 4-5.

Preferably, the core diameter d of the optical fiber constituting the large end is not less than 2 μm.

Preferably, the length L of the optical fiber cone along the axial direction of the optical fiber is more than or equal to 0.8D, wherein D is the diameter of the large end or the equivalent diameter of the large end.

The equivalent diameter in the technical scheme of the invention is that when the section of the big end is not circular, the diameter of the equivalent circle can be converted according to the area of the section of the big end, for example, when the big end is a square with side length lmm, the area of the equivalent circle is 1mm²Then the equivalent diameter is about 1.13mm as calculated from the area formula of the circle.

The light cone is designed into a bent light cone with a large end straight region and a small end straight region which are not coaxial, and the input end face and the output end face of the light cone are set to be of structures that the end face of a core layer and the end face of a skin layer are located on different planes, so that the core layer exceeds the skin layer to enable the end face of the core layer to be of a convex spherical structure, or the skin layer exceeds the core layer to enable the end face of the core layer to be of a concave spherical structure. Through the combined application of straight district structure and sandwich layer terminal surface structure, make and assemble incident light at the input end face, assemble emergent light at the output end face, the problem of light cone output terminal surface light beam divergence and output terminal surface slope has been overcome, make the light cone incide CCD's light automatic aggregation, avoid dispersing, the crosstalk of light between the optic fibre has been reduced, the decline of resolution ratio has been suppressed, the efficiency of light cone and CCD coupling has been improved, light transmissivity and resolution ratio, the imaging quality of coupling has been promoted, simultaneously the bent shape design of main aspects and tip disalignment has reduced the radiation damage of high energy ray to coupling device again, the radiation resistance of device has been improved, digital shimmer imaging has been promoted, the improvement of particle detection technique.

The invention also proposes the use of an optical fiber taper according to the above.

The invention also proposes the use of an optical fiber cone according to the above in the field of particle detection, such as the light cone shown in example 1 below.

The invention also proposes the use of an optical fiber taper according to the above in the field of low-light night vision imaging, such as the taper shown in example 2 below.

The following is further illustrated by the more specific examples: