Optical fiber panel with high uniformity and high transmittance, preparation method and application thereof

Abstract

The present invention relates to a high-uniformity, high-transmittance optical fiber panel and its preparation method and application. The high-uniformity, high-transmittance optical fiber panel comprises an output end, an input end, and an optical fiber portion arranged between the output end and the input end; the surface of the output end and / or the input end has a thin film whose thickness gradually decreases from the center to the edge; the thickness and position of the thin film satisfy: x = -2×10 ‑7 y 6 +8×10 ‑17 y 5 +1×10 ‑4 y 4 ‑2×10 ‑14 y 3 ‑0.0315y 2 ‑1×10 ‑11 y+4.2165, where x is the absolute thickness of the film, and y is the distance from the center to the edge. The technical problem to be solved is to obtain a high uniformity and high transmittance optical fiber panel by coating a homogenizing film.

Description

Technical Field

[0001] The present invention relates to an optical fiber image transmission element, and in particular to an optical fiber panel with high uniformity and high transmittance, and a preparation method and application thereof. Background Art

[0002] The fiber optic panel is a hard fiber optic array composed of tens of millions or even hundreds of millions of micron-sized glass optical fibers. Each optical fiber is a relatively independent minimum light and image transmission unit. When the panel is coated with a photocathode and phosphor, it can be used as the light input and output windows of the low-light image intensifier respectively. It has the characteristics of high light transmission efficiency, low coupling loss, clear and real transmitted images, and zero optical thickness. It can transmit proportional high-definition images and is widely used in various cathode ray tubes, camera tubes, CCD couplers and other instruments and equipment that need to transmit images.

[0003] The key gap in the existing technology is the low coupling efficiency between the optical fiber panel and the optoelectronic coupling device, especially the low edge light transmittance, poor edge coupling resolution, and poor imaging clarity, which is closely related to the preparation process of the optical fiber panel. The optical fiber panel is obtained by melting and pressing tens of millions or even hundreds of millions of micron-level fibers. During the melting and pressing process, the edge area and the center area are subjected to different forces, which will force the optical fiber in the edge area to deform slightly, affecting the transmission of light and forming a phenomenon of high transmittance in the center and low transmittance at the edge. This non-uniform transmittance will directly affect the coupling efficiency. Summary of the invention

[0004] In view of this, the main purpose of the present invention is to provide a high-uniformity, high-transmittance optical fiber panel and its preparation method and application. The technical problem to be solved is to obtain a high-uniformity, high-transmittance optical fiber panel by coating a homogenizing film.

[0005] The purpose of the present invention and the technical problem to be solved are achieved by adopting the following technical solutions. The present invention proposes a high uniformity and high transmittance optical fiber panel, comprising an output end, an input end and an optical fiber portion arranged between the output end and the input end; the surface of the output end and / or the input end has a thin film whose thickness gradually decreases from the center to the edge; the thickness and position of the thin film satisfy: x = -2×10 -7 y 6 +8×10 -17 y 5 +1×10 -4 y 4 -2×10 -14 y 3 -0.0315y 2 -1×10 -11 y+4.2165, where: x is the absolute thickness of the film, y is the distance from the center to the edge.

[0006] Furthermore, in the aforementioned optical fiber panel with high uniformity and high transmittance, the value of x is greater than 0, and the value of y is between 0 and 11.5.

[0007] Furthermore, in the aforementioned optical fiber faceplate with high uniformity and high transmittance, the thin film includes a homogenizing film layer and / or an anti-reflection film layer, and a film layer center is arranged at the center thereof.

[0008] The purpose of the present invention and the solution to its technical problems can also be achieved by adopting the following technical solutions. The present invention proposes a method for preparing a high-uniformity and high-transmittance optical fiber panel, comprising the following steps:

[0009] The surface of the optical fiber panel is coated with a thin film whose thickness gradually decreases from the center to the edge.

[0010] Furthermore, in the aforementioned method for preparing a high-uniformity, high-transmittance optical fiber panel, the coating rotation speed is 10rpm-15rpm.

[0011] Furthermore, in the aforementioned method for preparing a high-uniformity, high-transmittance optical fiber panel, the coating pressure is 0.8-1.0Pa.

[0012] Furthermore, in the above-mentioned method for preparing a high-uniformity and high-transmittance optical fiber panel, the vacuum degree of the coating is less than 2×10 -4 .

[0013] Furthermore, in the aforementioned method for preparing a high-uniformity, high-transmittance optical fiber panel, the gas flow rates of argon and oxygen during coating are 20-30 sccm, and the volume ratio of the two is 1:1.

[0014] Furthermore, in the aforementioned method for preparing a high-uniformity, high-transmittance optical fiber panel, the coating is achieved by sputtering; pre-sputtering starts at 30-50W, and after sputtering for 3-5 minutes, the power is adjusted to 60-80W to start formal sputtering, and the sputtering time is 0.5-3 minutes.

[0015] The purpose of the present invention and the technical problems solved therein can also be achieved by adopting the following technical solutions: The present invention provides a cathode ray tube, which comprises the above-mentioned optical fiber panel with high uniformity and high transmittance.

[0016] The purpose of the present invention and the technical problems solved therein can also be achieved by adopting the following technical solutions: The present invention provides a camera tube, which comprises the above-mentioned optical fiber panel with high uniformity and high transmittance.

[0017] The purpose of the present invention and the technical problems solved therein can also be achieved by adopting the following technical solutions: The present invention proposes a low-light-level image intensifier, which comprises the above-mentioned optical fiber panel with high uniformity and high transmittance.

[0018] The purpose of the present invention and the technical problem solved by the present invention can also be achieved by adopting the following technical solutions: The present invention proposes a CCD coupler, which includes the above-mentioned high-uniformity, high-transmittance optical fiber panel.

[0019] By means of the above technical solution, the optical fiber panel with high uniformity and high transmittance and its preparation method and application described in the present invention have at least the following advantages:

[0020] According to the non-uniform transmittance design of the optical fiber panel, a homogenizing film is plated on the surface of the optical fiber panel to effectively improve the non-uniform transmittance in the effective area. The homogenizing film has a thickness gradient trend that gradually decreases from the center to the edge. The prepared optical fiber panel can effectively improve the resolution of the optical fiber panel.

[0021] The present invention aims at the problem of uneven light transmittance at the output end face of the optical fiber panel. The invention is designed from the surface microstructure of the optical fiber panel, which can greatly improve the transmittance non-uniformity, make the output light of the optical fiber panel uniform, and reduce the brightness difference between the periphery and the center area of ​​the optical fiber panel.

[0022] The non-uniform transmittance of the optical fiber panel prepared by the present invention can reach 0.81%-1.37% at a wavelength of 550nm, the transmittance uniformity can reach 98.63%-99.19%, and the central transmittance can reach 42.60%-42.83%.

[0023] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the mechanical rotary coating device of the present invention;

[0025] Figure 2 It is a schematic diagram of the structure of the mechanical rotary coating device without a protective shell of the present invention;

[0026] Figure 3 It is a partial cross-sectional perspective view of the mechanical spin coating device of the present invention;

[0027] Figure 3A It is a schematic diagram of the structure of the rotating base of the mechanical rotating film coating device of the present invention;

[0028] Figure 4A diagram of a snail-shaped mask of a mechanical rotary coating device of the present invention;

[0029] Figure 5A It is a schematic diagram of the structure of the optical fiber panel with a homogenizing film deposited on the input end of the present invention;

[0030] Figure 5B This is a schematic diagram of the structure of an optical fiber panel with a homogenizing film deposited on the input end and an anti-reflection film deposited on the output end of the present invention;

[0031] Figure 5C It is a schematic structural diagram of an optical fiber panel with a homogenizing film deposited on the output end of the present invention;

[0032] Figure 5D This is a schematic diagram of the structure of an optical fiber panel with a homogenizing film deposited on the output end and an anti-reflection film deposited on the input end of the present invention;

[0033] Figure 5E It is a schematic structural diagram of an optical fiber panel with equalization films deposited at both ends of the present invention;

[0034] Fig. 5F This is a schematic diagram of the structure of an optical fiber panel of the present invention in which a leveling film is deposited on the input end and a leveling film + an anti-reflection film is deposited on the output end;

[0035] Figure 5G It is a schematic diagram of the structure of the optical fiber panel with equalization film + anti-reflection film deposited on both ends of the present invention;

[0036] Figure 5H This is a schematic diagram of the structure of the optical fiber panel of the present invention in which a homogenizing film is deposited on the output end and a homogenizing film + an anti-reflection film is deposited on the input end;

[0037] Figure 6 This is a graph showing the transmittance test results before and after coating of Example 1 of the present invention;

[0038] Figure 7 This is a graph showing the transmittance test results before and after coating of Example 2 of the present invention;

[0039] Figure 8 The transmittance test result diagram of Comparative Example 1 before and after coating;

[0040] Among them: 1-protective shell; 2-motor; 3-small gear; 4-large gear; 5-rotating base; 6-mask plate; 7-sample chamber; 8-platform; output end-9; input end-10; homogenizing film-11; anti-reflection film-12; film layer center-13; film layer center-14. DETAILED DESCRIPTION

[0041] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the high uniformity and high transmittance optical fiber panel and its preparation method and its specific implementation method, features and effects proposed by the present invention in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "embodiment" does not necessarily refer to the same embodiment. In addition, specific features or characteristics in one or more embodiments may be combined in any suitable form.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present invention belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" in the specification and claims of the present invention and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0043] In the description of the embodiments of the present invention, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present invention, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0044] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0045] In the description of the embodiments of the present invention, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0046] In the description of the embodiments of the present invention, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0047] In the description of the embodiments of the present invention, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the embodiments of the present invention.

[0048] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0049] Design and preparation of homogenization film on the surface of optical fiber panel

[0050] Using conventional methods (without mechanical rotary coating equipment and mask plate) to coat a film of uniform thickness on the surface of the optical fiber panel can only change the overall transmittance of the optical fiber panel, but cannot improve the problem of different brightness between the edge and the center of the optical fiber panel, and cannot achieve a high uniform transmittance effect. Therefore, a snail-shaped mask plate is designed to achieve a film with a thickness that gradually decreases from the center to the edge, based on the non-uniform transmittance characteristics of the optical fiber panel. Figure 4 As shown in FIG. 1 , the shaded part is the hollow part, and the shape is designed according to the non-uniform transmittance of the optical fiber panel. First, a transmittance tester (i.e., a device for detecting the visible light transmittance and uniformity of an optical fiber imaging element involved in the patent application with the publication number CN 111442908A) is used to obtain the transmittance distribution of the optical fiber panel. Next, the functional relationship between the transmittance of the optical fiber panel and the position of the effective area is obtained by fitting the obtained data. Then, the function of the film thickness and position of the required coating layer is calculated by the function. -7 y 6 +8×10 -17 y 5 +1×10 -4 y 4 -2×10 -14 y 3 -0.0315y 2 -1×10 -11y+4.2165, where: x is the absolute thickness of the film layer, y is the distance from the center to the edge (x is greater than 0, y is between 0-11.5), and finally according to the formula The shape of the snail mask is obtained by and ρ = (1-d / H)r. Among them, θ(x) is the angle exposed to the steam flow, d0 is the thickness at the center of the film layer, θ0 is the opening angle at the center of the film layer, the distance between the evaporation source and the lower surface of the substrate to be plated is H, the distance between the shield and the lower surface of the substrate is d, the polar diameter from the center of the shield to the opening reference point is ρ, and the maximum radius of the glass substrate that the evaporation source can reach is r. Figure 4 As shown, the opening size of the snail-shaped mask plate tends to gradually decrease from the center to the edge. In conjunction with a mechanical rotary coating device, the middle area is exposed for a long time and the edge area is exposed for a short time during the coating process, so that the target film layer can be obtained.

[0051] By using a rotary coating device in conjunction with a snail-shaped mask, a thin film with a thickness that gradually decreases from the center to the edge can be plated, and with a fiber optic panel with non-uniform transmittance, a fiber optic panel with high uniform light transmittance can be finally achieved. In actual use, the homogenizing film can be plated on both ends or at the same time, and it can also be matched with an anti-reflection film to achieve high transmittance and ultra-high light transmittance.

[0052] The mechanical spin coating device is as follows: Figure 1-4 As shown, it includes a protective shell 1, a motor 2, a small gear 3, a large gear 4, a rotating base 5, a mask 6, a sample chamber 7, a platform 8 and a sample 9 fixed by screws. The protective shell 1 is fixedly connected to the platform 8, so that the whole device is in a regular shape (a rectangular parallelepiped with a length of 173mm, a width of 136mm and a height of 115mm), which is convenient for placement in the chamber. Among them, the platform 8 is a rectangular metal plate with a thickness of 3mm, so that the size can be reduced as much as possible while ensuring that the motor, sample chamber and other components can bear the load; as shown in FIG. Figure 3AAs shown, the rotating base 5 is a bearing structure composed of two concentric rings, which includes a non-rotating internal structure and a rotating external structure connected by steel balls, the internal structure is fixed to the sample chamber 7, the upper end face of the external structure is fixed to the large gear 4, and the lower end face of the external structure is fixed to the mask plate 6, so that the mask plate can be rotated and the sample chamber does not rotate. Specifically, the rotating base 5 is a high-precision bearing, the gap inside the bearing is very small, the distance between the two is filled with steel balls, the stability is very high, and there is no shaking, thereby ensuring high coaxiality. Since the rotating base 5 is a three-dimensional structure and is located between the sample chamber 7 and the mask plate 6, according to the direction of placing the mechanical rotary coating device on the coating equipment, the sample chamber 7 is fixed above the inside of the rotating base 5, and the mask plate 6 is fixed below the outside of the rotating base 5. The sample 9 is a fiber panel, and there is no requirement for its size and performance. Fiber panels of different sizes can be placed by changing the size of the sample chamber. The rotating base 5 is fixed to the mask plate 6, and the motor drives the rotating base 5 to rotate, while the sample chamber 7 remains stationary, so that the effect of the mask plate 6 rotating can be achieved. By using a mechanical rotary coating device in conjunction with a snail-shaped mask plate 6, a thin film with a thickness gradually decreasing from the center to the edge can be plated, and in combination with an optical fiber panel with non-uniform transmittance, a highly uniform and high transmittance optical fiber panel can be finally achieved.

[0053] The sample 9 is placed in the sample chamber 7. The sample chamber 7 is 4mm higher than the sample and has a built-in rubber pad to prevent the end face of the sample 9 from being damaged when the mechanical rotary coating device is inverted and disassembled. Specifically, the rubber pad is located between the large end face of the optical fiber panel and the sample chamber 7. This arrangement can prevent the large end face of the optical fiber panel from directly contacting the sample chamber 7; and the material of the sample chamber 7 is polytetrafluoroethylene. The reason for choosing polytetrafluoroethylene is first because it is light in weight and can reduce the overall weight of the device; secondly, it is because it can withstand higher temperatures than ordinary plastics. The upper end face of the sample chamber 7 is fixed to the platform 8 by screws, and its lower end face is fixed to the upper end face of the internal structure of the rotating base 5 by screws. The sample chamber 7 is a cylindrical groove with a diameter of 48mm and a depth of 45mm. One end of the platform 8 is fixed to the motor 2 by screws to ensure that the mask rotates without interference while ensuring the coating effect.

[0054] A small-diameter pinion 3 is installed at the tail end of the shaft of the motor 2. The rotation of the motor 2 drives the pinion 3 to rotate. This arrangement is to ensure that the rotation of the mask is not disturbed while ensuring the coating effect.

[0055] The pinion 3 is meshed and connected with the large diameter and hollow large gear 4, and the rotation of the pinion 3 drives the large gear 4 to rotate. In specific implementation, the diameter of the large gear 4 needs to be equal to the diameter of the outer side of the bearing. Considering that the sample chamber 7 needs to be placed in the middle of the large gear 4, the large gear 4 is set to be hollow. Among them, the diameter of the large gear 4 is consistent with the size of the rotating base, and the speed ratio of the pinion 3 and the large gear 4 is 5:1, at this time, the film formation uniformity is good; according to the speed ratio, the pinion 3 of the appropriate diameter is selected, and the speed is too fast or too slow, which is easy to cause poor film formation uniformity and stains on the surface of the film layer. The speed ratio design between the large and small gears is to control the speed of the bottom mask and improve the uniformity of the coating thickness. Combined with the position of the pinion and the speed ratio, the diameter of the pinion 3 is designed to be 3cm. At the same time, the mechanical rotary coating device can use large and small gears to drive in a limited space, so that the transmission efficiency is higher.

[0056] The motor 2 drives the small gear 3 to rotate, the small gear 3 drives the large gear 4 to rotate, the large gear 4 drives the outer part of the bearing to rotate, and the outer part of the bearing drives the mask to rotate, so that the sample does not rotate but the mask rotates by itself.

[0057] The large gear 4 is fixed to the upper end of the outer side of the rotating base 5 by screws. The rotation of the large gear 4 drives the rotating base 5 to rotate. There is a 1-2mm gap between the large gear 4 and the sample chamber 7 so that the large gear 4 will not be affected by the sample chamber 7 when rotating.

[0058] The outer lower end surface of the rotating base 5 is fixed to the mask 6 by screws, and the outer part of the rotating base 5 drives the mask 6 to rotate. The size of the mask 6 is equal to the outer size of the rotating base 5, and the gap between the two is 2mm, so that the mask 6 rotates without interference while ensuring the coating effect. Specifically, the mask 6 is a hollowed-out spiral copper plate with a thickness of 0.5mm and a diameter of 120mm. The hollowed-out middle part of the spiral copper plate has a larger opening, and the edge part has a smaller opening, that is, the middle exposure time is long and the edge exposure time is short during coating, which can achieve a gradient film with a thick middle film layer and a thin edge film layer. The thinner the copper plate is, the better it is on the premise of ensuring that the mask plate is not deformed, so that the sputtering material can be better attached to the sample; it has been found through testing that a mask plate with a thickness of less than 0.5mm is easy to deform. Considering that the mask 6 is fixed to the rotating base by screws, the diameter of the mask 6 is the same as the outer size of the rotating base to facilitate fixation.

[0059] The coating of the thin film optical fiber panel with thickness gradually decreasing from the center to the edge includes the following steps:

[0060] 1) Place the assembled mechanical rotary coating device into the chamber of the magnetron sputtering coating machine; the chamber has good sealing performance and can be used to place samples or devices to be coated; if the mask plate is installed first, the sample cannot be installed, so if the device needs to be used, the sample must be installed first and then the mask plate;

[0061] 2) Turn on the power supply and adjust the speed of the mechanical rotary coating device; since the motor speed of the mechanical rotary coating device is adjustable, the motor speed can be adjusted to 10-15 rpm by turning the button;

[0062] 3) Closing the chamber and starting the coating. Closing the chamber and starting the coating specifically includes the following steps:

[0063] a. After closing the chamber of the coating equipment, turn on the mechanical pump to pre-vacuum. When the vacuum degree is lower than 10Pa, turn off the mechanical pump, open the solenoid valve, and turn on the molecular pump.

[0064] b When the vacuum degree is lower than 2×10 -4 The gas flowmeter was turned on and the gas flow rates of argon and oxygen were adjusted to 20-30 sccm. Then the pressure in the chamber was adjusted to 0.8-1.0 Pa through the G valve. The vacuum degree was less than 2×10 -4 It can meet the coating requirements. The lower the vacuum degree, the fewer impurities in the chamber; the lower the pressure in the chamber, that is, the working pressure, the higher the quality of the coated film, but the speed will be slower, so 0.8-1.0Pa is selected as the working pressure.

[0065] c. Turn on the sputtering power switch and adjust the power to 30-50W to start pre-sputtering. After sputtering for 3-5 minutes, open the baffle valve and adjust the power to 60-80W to start formal sputtering. The sputtering time is 0.5-3 minutes. The function of pre-sputtering is first to preheat the machine. It is not advisable to use high power when starting the machine. Secondly, it sputters away impurities on the surface of the target material.

[0066] d. After sputtering is completed, close the flapper valve, turn off the power switch, turn the gas flow meter knob to 0, close the solenoid valve, turn off the molecular pump, and open the valve connected to the air to balance the internal and external atmospheric pressure of the chamber;

[0067] eOpen the chamber of the coating equipment and take out the mechanical rotary coating device. After the coating is completed, a high uniformity and high transmittance optical fiber panel is obtained. Figure 5A , Figure 5B , Figure 5C , Figure 5D , Figure 5E , Fig. 5F , Figure 5G and Figure 5H As shown, the optical fiber panel can be used in a cathode ray tube, a camera tube, a low-light image intensifier or a CCD coupler. Figure 5A , Figure 5B, Figure 5C , Figure 5D , Figure 5E , Fig. 5F , Figure 5G and Figure 5H It can be seen that both the input and output end faces of the optical fiber panel can be coated with a homogenized film layer, and even both ends can be coated with a homogenized film layer at the same time. There are a total of 5 coating methods. Specifically, Figure 5A , Figure 5B , Figure 5C , Figure 5D , Figure 5E , Fig. 5F , Figure 5G and Figure 5H As shown, the optical fiber panel includes an output end 9, an input end 10 and an optical fiber portion arranged between the output end 9 and the input end 10; the surface of the output end 9 and / or the input end 10 has a thin film whose thickness gradually decreases from the center to the edge; the thickness and position of the thin film satisfy: x = -2×10 -7 y 6 +8×10 -17 y 5 +1×10 -4 y 4 -2×10 -14 y 3 -0.0315y 2 -1×10 -11 y+4.2165, where: x is the absolute thickness of the film, y is the distance from the center to the edge. The film comprises a homogenizing film layer 11 and / or an anti-reflection film layer 12, wherein a film layer center 13 is disposed at the center of the homogenizing film layer 11, and a film layer center 14 is disposed at the center of the anti-reflection film layer 12.

[0068] The above-mentioned “high uniformity and high transmittance” means that the transmittance uniformity of the optical fiber panel at a wavelength of 550 nm is between 98.63% and 99.19%, and the central transmittance is between 42.6% and 42.83%.

[0069] The present invention is described in detail below with reference to specific embodiments.

[0070] The “center” mentioned below refers to the exact center of the fiber optic panel, and the “edge” refers to the edge of the effective area of ​​the fiber optic panel.

[0071] Embodiment 1:

[0072] This embodiment provides a high uniformity and high transmittance optical fiber panel, the manufacturing of which specifically includes the following steps:

[0073] S1, use the rod-tube combination method to combine a high-refractive-index glass rod and a low-refractive-index glass tube together and then draw (temperature is 1850°C) into a single filament (diameter is 3mm); the drawn single filament and the light-absorbing filament for absorbing stray light (diameter is 3mm) are arranged into a hexagonal shape and then drawn (temperature is 1845°C) into a primary multifilament (diameter is 1.3mm); the primary multifilament is arranged into a hexagonal shape again and drawn (temperature is 1450°C) into a secondary multifilament (diameter is 2mm); the secondary multifilament is placed in a melt-pressed mold and subjected to high temperature and high pressure to prepare a blank (height is 50mm, diameter is 20mm). The glass rod has a refractive index of 1.78 at a wavelength of 550 nm, and its composition by weight percentage is: SiO2 54.12%; K2CO3 14.84%; Na2CO3 11.10%; Al(OH)3 5.99%; H2BO3 10.16%; CaCO3 2.88%; BaCO3 0.23%; CeO2 0.07%; MgCO3 0.46%; NiO 0.01%; Nb2O5 0.05%; Y2O3 0.01%; La2O3 0.08%. The refractive index of the glass tube at a wavelength of 550 nm is 1.49, and its composition by weight percentage is: SiO2 35.25%; KNO3 0.13%; Na2CO3 0.10%; Al(OH)3 0.84%; H2BO3 24.23%; CaCO3 10.26%; BaCO3 25.50%; MgCO3 0.21%; La2O3 1.68; Sb2O3 0.06%; TiO2 1.74%. The composition of the light absorbing filament in weight percentage is: SiO2 55.84%; K2CO3 11.27%; Na2CO3 6.11%; Al(OH)3 9.37%; H2BO3 8.56%; CaCO3 2.67%; BaCO3 0.03%; CeO2 0.19%; MgCO3 0.40%; Fe2O3 0.02%; NiO 0.87%; MnO2 2.87%; CoO 0.42%; La2O3 0.01%; V2O5 1.37%.

[0074] S2, polish the cut optical fiber panel blanks for 2 hours, and the roughness reaches 20nm. Then perform performance testing to ensure that the transmittance, resolution and internal defects (such as defects, chicken wire, grid) of the optical fiber panel meet the national standards (GJB 2177-1994 General Specifications for Optical Fiber Panels).

[0075] S3, first use the transmittance tester (i.e. the device for detecting the visible light transmittance and uniformity of the optical fiber image transmission element involved in the patent application with publication number CN 111442908A) to test the transmittance distribution at the output end of the optical fiber panel, and then analyze the obtained data to obtain a non-uniform transmittance of 4.63% and a center transmittance of 46.13%. Then use a rotary coating device to coat a layer of gradient metal chromium film with a center thickness of 2nm and an edge thickness of 0.5nm, reducing the non-uniform transmittance to 0.81% and the center transmittance to 42.83%. The test results are as follows Figure 6 shown.

[0076] Specifically, the assembled rotary coating device is placed in the chamber of the magnetron sputtering coating machine; the power supply is turned on, and the rotation speed of the rotary coating device is adjusted to 10 rpm; the chamber is closed to start coating, and the distance between the mask plate and the optical fiber panel is 1 mm.

[0077] The method of closing the chamber and starting the coating specifically comprises the following steps: a. after closing the chamber of the coating equipment, first open the mechanical pump to pre-vacuum, and when the vacuum degree reaches 10Pa, close the mechanical pump, open the solenoid valve, and turn on the molecular pump; b. when the vacuum degree reaches 2×10 -4 1. Turn on the gas flowmeter and adjust the gas flow of argon and oxygen in a volume ratio of 1:1 to 25sccm. Next, adjust the pressure in the chamber to 0.8Pa through the G valve; c. Turn on the sputtering power switch and adjust the power to 50W to start pre-sputtering. After sputtering for 5 minutes, open the baffle valve and adjust the power to 60W to start formal sputtering. The sputtering time is 15s; d. After sputtering, close the baffle valve, turn off the power switch, turn the gas flowmeter knob to 0, turn off the solenoid valve, turn off the molecular pump, and open the valve connected to the air to balance the internal and external atmospheric pressures of the chamber; e. Open the chamber of the coating equipment, take out the rotary coating device, and the coating is completed to obtain a fiber optic panel with high uniformity and high transmittance.

[0078] from Figure 6 It can be seen that the thickness of the chrome film gradually decreases from the center to the edge. It can be seen that the transmittance at the center of the optical fiber panel decreases from 46.13% to 42.83%, and the non-uniform transmittance decreases from 4.63% to 0.81%, indicating that the mask is reasonably designed and can successfully reduce vignetting defects.

[0079] Embodiment 2:

[0080] This embodiment provides a high uniformity and high transmittance optical fiber panel, the manufacturing of which specifically includes the following steps:

[0081] S1, same as Example 1.

[0082] S2, same as Example 1.

[0083] S3, compared with Example 1, the difference of this embodiment is that a layer of gradient titanium nitride film with a center thickness of 10nm and an edge thickness of 2nm is plated using a rotary coating device. The test results show that the non-uniform transmittance is reduced to 1.37%, and the center transmittance is 42.6%. The test results are as follows Figure 7 shown.

[0084] Specifically, the assembled rotary coating device is placed in the chamber of the magnetron sputtering coating machine; the power supply is turned on, and the rotation speed of the rotary coating device is adjusted to 10 rpm; the chamber is closed to start coating, and the distance between the mask plate and the optical fiber panel is 1 mm.

[0085] The method of closing the chamber and starting the coating comprises the following steps: a. after closing the chamber of the coating equipment, first open the mechanical pump to pre-vacuum, and when the vacuum degree reaches 10Pa, close the mechanical pump, open the solenoid valve, and turn on the molecular pump; b. when the vacuum degree reaches 2×10 -4 1. Turn on the gas flowmeter and adjust the gas flow of argon and oxygen in a volume ratio of 1:1 to 25sccm. Next, adjust the pressure in the chamber to 0.8Pa through the G valve; c. Turn on the sputtering power switch and adjust the power to 50W to start pre-sputtering. After sputtering for 5 minutes, open the baffle valve and adjust the power to 60W to start formal sputtering. The sputtering time is 50s; d. After sputtering, close the baffle valve, turn off the power switch, turn the gas flowmeter knob to 0, turn off the solenoid valve, turn off the molecular pump, and open the valve connected to the air to balance the internal and external atmospheric pressures of the chamber; e. Open the chamber of the coating equipment, take out the rotary coating device, and the coating is completed to obtain a fiber optic panel with high uniformity and high transmittance.

[0086] from Figure 7 It can be seen that after the coating material is changed to titanium nitride, the transmittance at the center of the optical fiber panel is reduced from 46.13% to 42.6%, and the non-uniform transmittance is reduced from 4.63% to 1.37%. This shows that the use of a rotary coating device for coating layers of other materials can also achieve the purpose of reducing vignetting defects.

[0087] Comparative Example 1:

[0088] Compared with Example 1, the difference of this comparative example is that the rotary coating device is not used during the coating, and a metal chromium film with a thickness of 2nm in the edge and center areas is plated by a conventional method. After testing, it is found that the non-uniform transmittance is reduced to 3.19%, and the center transmittance is 41%. The test results are as follows: Figure 8 As shown. Figure 8 It can be seen that the film thickness of the chrome film gradually decreases from the center to the edge. It can be seen that the transmittance at the center of the optical fiber panel decreases from 46.13% to 41%, and the vignetting defect decreases from 4.63% to 3.19%, which shows that the vignetting defect cannot be effectively reduced without the use of a rotary coating device.

[0089] The non-uniform transmittance and center transmittance of the optical fiber panels of Examples 1-2 and Comparative Example 1 before and after coating were tested, and the test results are shown in Table 1. The test principle is: a beam of collimated incident light with a wavelength of 550nm is irradiated to the input end of the optical fiber panel, and the light from the output end of the optical fiber panel is received by a CCD camera to obtain a light intensity distribution diagram, and the relative transmittance is calculated by the luminous flux of the input and output light. Among them, the luminous flux is equal to the light intensity multiplied by the area, and the light intensity is measured by the transmittance tester. The center transmittance is the transmittance when the position is 0 (the center of the optical fiber panel). The non-uniform transmittance is the difference between the center transmittance and the transmittance at the edge of the effective area.

[0090] Table 1

[0091]

[0092] From the data in Table 1, it can be concluded that before coating, when the central transmittance of Example 1-2 was maintained at 46.13%, the non-uniform transmittance of the optical fiber panel was 4.63%, and the transmittance uniformity was 95.37%. After coating, while ensuring that the non-uniform transmittance was around 1% on average, the average central transmittance of the optical fiber panel could reach 42.7%. It can also be shown that the use of a rotary coating device to coat homogenized films of different film materials can achieve the purpose of reducing vignetting defects. Comparing Comparative Example 1 with Example 1, it can be found that coating a chrome film without a rotary coating device cannot effectively reduce vignetting defects.

[0093] In the specification of the present invention, a lot of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some embodiments, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this specification.

[0094] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0095] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

[0096] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A high uniformity and high transmittance optical fiber panel, characterized in that: The invention comprises an output end, an input end and an optical fiber part arranged between the output end and the input end; the surface of the output end and / or the input end has a thin film whose thickness gradually decreases from the center to the edge; the thickness and position of the thin film satisfy: x = -2×10 -7 y 6 +8×10 -17 y 5 +1×10 -4 y 4 -2×10 -14 y 3 -0.0315y 2 -1×10 -11 y+4.2165, where: x is the absolute thickness of the film, y is the distance from the center to the edge.

2. The optical fiber panel with high uniformity and high transmittance as claimed in claim 1, characterized in that: The value of x is greater than 0, and the value of y is between 0 and 11.

5.

3. The optical fiber panel with high uniformity and high transmittance as claimed in claim 1, characterized in that: The film comprises a homogenizing film layer and / or an anti-reflection film layer, and a film layer center is arranged at the center thereof.

4. The optical fiber panel with high uniformity and high transmittance as claimed in claim 1, characterized in that: The optical fiber panel with high uniformity and high transmittance is prepared by the following steps: The surface of the optical fiber panel is coated with a thin film whose thickness gradually decreases from the center to the edge.

5. The optical fiber panel with high uniformity and high transmittance as claimed in claim 4, characterized in that: The rotation speed when plating the thin film whose thickness gradually decreases from the center to the edge is 10rpm-15rpm.

6. The optical fiber panel with high uniformity and high transmittance as claimed in claim 4, characterized in that: The pressure when plating the film whose thickness gradually decreases from the center to the edge is 0.8-1.0Pa.

7. The optical fiber panel with high uniformity and high transmittance as claimed in claim 4, characterized in that: When coating the thin film whose thickness gradually decreases from the center to the edge, the gas flow rates of argon and oxygen are 20-30 sccm, and the volume ratio of the two is 1:

1.

8. The optical fiber panel with high uniformity and high transmittance as claimed in claim 4, characterized in that: The coating of the thin film with thickness gradually decreasing from the center to the edge is achieved by sputtering; the power is adjusted to 30-50W to start pre-sputtering, and after sputtering for 3-5 minutes, the power is adjusted to 60-80W to start formal sputtering, and the sputtering time is 0.5-3 minutes.

9. A cathode ray tube, characterized in that: The cathode ray tube comprises the optical fiber faceplate with high uniformity and high transmittance as claimed in any one of claims 1 to 8.

10. A camera tube, characterized in that: The camera tube includes the optical fiber panel with high uniformity and high transmittance as described in any one of claims 1-8.

11. A low-light level image intensifier, characterized in that: The low-light image intensifier comprises the optical fiber panel with high uniformity and high transmittance as described in any one of claims 1-8.

12. A CCD coupler, characterized in that: The CCD coupler comprises the optical fiber panel with high uniformity and high transmittance as described in any one of claims 1-8.

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