Dewar for testing transmittance of filter lens in low-temperature environment

Abstract

The utility model relates to the technical field of infrared filter lens testing, and discloses a transmittance testing Dewar for a filter lens in a low-temperature environment, which comprises an outer shell and an inner shell, and the outer shell is provided with a first light-transmitting part and a second light-transmitting part which are oppositely arranged. The inner shell is provided with a light-transmitting pipe and a fixing mechanism used for fixing the filter lens to one end of the light-transmitting pipe, an external light beam can horizontally and sequentially penetrate through the first light-transmitting part, the fixing mechanism, the light-transmitting pipe and the second light-transmitting part, the outer shell enables a closed space to be formed in the outer shell through a sealing cover plate, and the sealing cover plate is detachably connected with the outer shell. The first light-transmitting part is embedded in the shell, the second light-transmitting part is arranged on the sealing cover plate, the sealing cover plate is provided with a vacuum opening capable of being sealed, and an adsorption assembly used for maintaining the vacuum degree is arranged in the shell. The sealing performance is improved, and the lasting time of the vacuum state can be prolonged through the adsorption assembly.

Description

Technical Field

[0001] The utility model relates to the technical field of infrared filter lens testing, in particular to a transmittance testing dewar for filter lenses in a low-temperature environment. Background Art

[0002] Infrared detectors are used more and more widely in today's social development. Dewar, as an important component of infrared detectors, not only provides a vacuum environment for the infrared detector chip, but also provides a filter lens window for a specific band. Therefore, it has important index requirements for the transmittance of the filter lens. The filter lens works in a low-temperature vacuum environment. Therefore, when testing the transmittance of the filter lens, it is necessary to keep the filter lens in a low-temperature vacuum environment for testing. When testing the transmittance of the filter lens through a Dewar, there is often a problem of poor sealing, which leads to a short duration of the vacuum environment, which in turn reduces the accuracy of the test results.

[0003] In the prior art, a utility model patent (CN210625860U) discloses a low-temperature dewar for optical material spectral testing. The dewar is a vacuum-sealed container consisting of inner and outer metal cylinders. A dewar cold head, a test sample, a mechanical buffer ring, and a magnetic pressure ring are sequentially installed on a transition cold head to form a test sample fixing structure. During testing, if the dewar is used for a long time or the left and right sides are not assembled properly, air will enter the dewar from the buckles on both sides, thereby destroying the dewar's sealing. This results in poor sealing of the dewar and inconvenience in maintenance.

[0004] Based on this, the technical problem to be solved in this case is: how to improve the sealing of the test dewar and facilitate maintenance. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides a transmittance test dewar for filter lenses in low-temperature environments. The test dewar maintains a closed space inside the shell through a sealing cover, which can effectively prevent external gas from entering the shell, improve the sealing performance, and can extend the duration of the vacuum state inside the shell through an adsorption component.

[0006] The technical solution of the utility model is:

[0007] A dewar for testing the transmittance of a filter lens in a low-temperature environment comprises an outer shell and an inner shell. The outer shell is provided with a first light-transmitting portion and a second light-transmitting portion arranged opposite to each other. The inner shell is provided with a light pipe. The inner shell is also provided with a fixing mechanism for fixing the filter lens to one end of the light pipe. An external light beam can horizontally pass through the first light-transmitting portion, the fixing mechanism, the light pipe, and the second light-transmitting portion in sequence. The outer shell forms a closed space inside the outer shell through a sealing cover plate. The sealing cover plate is detachably connected to the outer shell. The first light-transmitting portion is embedded in the outer shell, and the second light-transmitting portion is arranged on the sealing cover plate. The sealing cover plate is also provided with a closable vacuum port. The outer shell is also provided with an adsorption component for maintaining the vacuum degree of the closed space.

[0008] In the above-mentioned Dewar for testing the transmittance of filter lenses in low-temperature environments, the fixing mechanism includes a cold stage and a fixing plate. The cold stage is located on one end of the light tube. The fixing plate is detachably connected to the cold stage. The fixing plate is used to fix the filter lens on the cold stage. The cold stage is provided with a first through hole for an external light beam to pass through, and the fixing plate is provided with a second through hole coaxially arranged with the first through hole.

[0009] In the above-mentioned dewar for testing transmittance of optical filters in a low-temperature environment, the fixing plate fixes the optical filters on the cold stage by means of a clamping connection, a bolt connection or a magnetic connection;

[0010] Preferably, if the fixing plate is connected by clamping, a first clamping member is provided on the cold stage and a second clamping member is provided on the fixing plate;

[0011] Preferably, if the fixing plate is connected by bolts, a plurality of first screw holes are provided on the fixing plate, and a second screw hole matching the first screw holes is provided on the cold stage;

[0012] Preferably, if the fixing plate is connected by magnetic attraction, the fixing plate is made of magnetic material, the cold stage is made of magnetic material, and a mechanical buffer block is provided between the fixing plate and the filter lens.

[0013] In the above-mentioned Dewar for testing the transmittance of filter lenses in a low-temperature environment, a channel for introducing liquid nitrogen is provided on the top of the inner shell, and the channel passes through the outer shell and communicates with the outside; a support column is provided at the bottom of the inner shell, and the support column is connected to the outer shell.

[0014] In the above-mentioned Dewar for testing transmittance of filter lenses in low temperature environments, a temperature measuring component is provided on the fixing mechanism.

[0015] In the above-mentioned Dewar for testing the transmittance of filter lenses in a low-temperature environment, a horizontal portion extending outward is provided on one side of the outer shell close to the temperature measuring component, a sealing cover is detachably connected to the horizontal portion, an electrical interface is provided on the horizontal portion, and the temperature measuring component is electrically connected to the electrical interface.

[0016] In the above-mentioned Dewar for testing the transmittance of filter lenses in a low-temperature environment, a sealing ring is provided on the side of the sealing cover plate close to the housing.

[0017] In the above-mentioned transmittance test dewar for a filter lens in a low-temperature environment, the first light-transmitting portion is a first optical lens, and the second light-transmitting portion is a second optical lens.

[0018] In the above-mentioned Dewar for testing transmittance of filter lenses in a low-temperature environment, the adsorption component is an activated carbon component, and the activated carbon component is located on the bottom of the shell.

[0019] In the above-mentioned Dewar for testing transmittance of filter lenses in a low-temperature environment, the vertical cross-section of the inner shell is in an inverted convex shape, and the light pipe is located at the narrow end of the inverted convex shape.

[0020] One of the above technical solutions of the utility model has at least one of the following advantages or beneficial effects:

[0021] The utility model maintains a closed space inside the shell through the sealing cover, which can effectively prevent external gas from entering the shell, improves the sealing performance, and can prolong the duration of the vacuum state inside the shell through the adsorption component. On the other hand, when the sealing cover is damaged, it will directly affect the sealing performance inside the shell, that is, it will cause the vacuum state to be unable to be formed inside the shell, and ultimately lead to test failure. Therefore, the detachable manner makes it convenient for staff to replace the damaged sealing cover, which is conducive to maintenance and replacement of the sealing cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a cross-sectional view of Example 1 of the present utility model;

[0023] Figure 2 It is the cross-sectional view of AA;

[0024] Figure 3 for Figure 1 A partial enlarged view of .

[0025] Among them, the specific reference numerals of each figure are as follows: 1. outer shell; 2. inner shell; 3. fixing mechanism; 4. sealing cover; 5. adsorption component; 6. filter lens; 11. first light-transmitting portion; 12. second light-transmitting portion; 13. horizontal portion; 21. light tube; 22. channel; 23. support column; 31. cold stage; 32. fixing plate; 33. temperature measuring component; 41. vacuum port; 42. sealing ring; 131. electrical interface; 311. first through hole; 312. first screw hole; 321. second through hole; 322. second screw hole. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] Example 1

[0028] See also Figures 1 to 3 A dewar for testing the transmittance of a filter lens in a low-temperature environment comprises an outer shell 1 and an inner shell 2. The outer shell 1 is provided with a first light-transmitting portion 11 and a second light-transmitting portion 12 arranged opposite to each other. The inner shell 2 is provided with a light-passing tube 21. The inner shell 2 is also provided with a fixing mechanism 3 for fixing the filter lens 6 to one end of the light-passing tube 21. An external light beam can pass through the first light-transmitting portion 11, the fixing mechanism 3, the light-passing tube 21 and the second light-transmitting portion 12 horizontally in sequence. The outer shell 1 forms a closed space inside the outer shell 1 through a sealing cover plate 4. The sealing cover plate 4 is detachably connected to the outer shell 1. The first light-transmitting portion 11 is embedded in the outer shell 1, and the second light-transmitting portion 12 is arranged on the sealing cover plate 4. The sealing cover plate 4 is also provided with a closable vacuum port 41. The outer shell 1 is also provided with an adsorption component 5 for maintaining the vacuum degree of the closed space.

[0029] It should be noted that the specific working environment of the filter lens 6 is in a low-temperature vacuum environment. Therefore, it is necessary to form a low-temperature vacuum environment in the test dewar and place the filter lens 6 in the dewar to test the transmittance. In actual operation, the staff fixes the filter lens 6 whose transmittance needs to be tested on one end of the light pipe 21 through the fixing mechanism 3, and emits a light beam to the first light-transmitting portion 11. The light beam passes through the first light-transmitting portion 11, the filter lens 6, the light pipe 21, and the second light-transmitting portion 12 in sequence and is emitted from one side of the housing 1. At this time, the transmittance of the filter lens 6 is obtained by measuring the emitted light beam and comparing it with the originally emitted light beam. After the staff fixes the filter lens 6, a closed space is formed inside the housing 1 through the sealing cover plate 4, and the housing is vacuumed at the vacuum port 41 by a vacuum pump. 1 is extracted, and finally the vacuum port 41 is closed, ultimately forming a vacuum state between the outer shell 1 and the inner shell 2. Specifically, the outer shell 1 and the inner shell 2 are in a live vacuum state. At this time, the adsorption component 5 can maintain the vacuum state between the outer shell 1 and the inner shell 2 for a long time. During the test process, if external gas enters the outer shell 1, it can only enter the outer shell 1 through the sealing cover 4. That is, in this way, the entire dewar can be made more integrated, thereby improving the sealing performance of the dewar. On the other hand, when batch testing the filter lenses 6, the sealing cover 4 cannot be avoided from being disassembled and installed multiple times, which will inevitably cause damage to the sealing cover 4, thereby affecting the maintenance of the vacuum state during testing. The detachable sealing cover 4 also facilitates the maintenance and replacement of the sealing cover 4 by the staff.

[0030] Furthermore, the fixing mechanism 3 includes a cold stage 31 and a fixing plate 32. The cold stage 31 is located on one end of the light tube 21. The fixing plate 32 is detachably connected to the cold stage 31. The fixing plate 32 is used to fix the filter lens 6 on the cold stage 31. The cold stage 31 is provided with a first through hole 311 for the external light beam to pass through. The fixing plate 32 is provided with a second through hole 321 coaxially arranged with the first through hole 311.

[0031] Through the above design, the cold stage 31 is conducive to transferring the temperature to the filter lens 6. Specifically, it is conducive to keeping the filter lens 6 in a low-temperature environment. The fixing plate 32 and the screws facilitate the staff to simply and quickly replace the filter lens 6 that needs to be tested. The first through hole 311 and the second through hole 321 can prevent the light beam from being blocked and unable to be emitted from the first light-transmitting portion 11 to the second light-transmitting portion 12.

[0032] Preferably, the fixing plate 32 fixes the filter lens 6 on the cold stage 31 by means of a snap connection, a bolt connection or a magnetic connection.

[0033] Through the above design, if the fixing plate 32 is connected by a clamping method, a first clamping part is provided on the cold stage 31, and a second clamping part is provided on the fixing plate 32; if the fixing plate 32 is connected by a bolt, a plurality of first screw holes 312 are provided on the fixing plate 32, and a second screw hole 322 matching the first screw holes 312 is provided on the cold stage 31; if the fixing plate 32 is connected by a magnetic attraction method, the fixing plate 32 is a fixing plate 32 made of a magnetic material, and the cold stage 31 is a cold stage 31 made of a magnetic material, and a mechanical buffer block is provided between the fixing plate 32 and the filter lens 6. In this embodiment, the filter lens 6 is fixed by a bolt connection because this method can more stably fix the filter lens 6 and is convenient for the staff to replace the filter lens 6.

[0034] Furthermore, a channel 22 for introducing liquid nitrogen is provided at the top of the inner shell 2 , and the channel 22 passes through the outer shell 1 and communicates with the outside; a support column 23 is provided at the bottom of the inner shell 2 , and the support column 23 is connected to the outer shell 1 .

[0035] Through the above design, the channel 22 allows the staff to pour liquid nitrogen from the top of the inner shell 2. The liquid nitrogen can make the temperature of the inner shell 2 drop rapidly, and this temperature can be transferred to the cold stage 31 through the inner shell 2, and then transferred to the filter lens 6. On the other hand, the channel 22 passes through the outer shell 1 and is connected to the outside, which is conducive to maintaining the closed vacuum environment between the outer shell 1 and the inner shell 2 during testing. On the other hand, the support column 23 can provide support for the inner shell 2 to prevent the inner shell 2 from being unstable, causing the light tube 21 located in the inner shell 2 to shift, or even shift to the point that the light beam cannot pass horizontally through the first light-transmitting part 11, the fixing mechanism 3, the filter lens 6, the light tube 21, and the second light-transmitting part 12 in sequence, resulting in failure to test normally. In this way, the contact area between the support column 23 and the inner shell 2 can be reduced, thereby reducing the heat transferred from the inner shell 2 to the support column 23, and increasing the duration of the low-temperature environment, which is conducive to long-term testing and batch testing.

[0036] More preferably, a temperature measuring component 33 is provided on the fixing mechanism 3 .

[0037] In the above design, since the filter lens 6 is fixed by the fixing mechanism 3, the temperature measuring component 33 can more accurately reflect the temperature environment of the filter lens 6, thereby ensuring that the test is started after the required temperature is reached.

[0038] More preferably, a horizontal portion 13 extending outward is provided on one side of the housing 1 close to the temperature measuring component 33 , the sealing cover 4 is detachably connected to the horizontal portion 13 , an electrical interface 131 is provided on the horizontal portion 13 , and the temperature measuring component 33 is electrically connected to the electrical interface 131 .

[0039] In this embodiment, the electrical interface 131 is connected to the temperature measuring component 33, and can be connected to an external display instrument through the electrical interface 131, so that the temperature measured by the temperature measuring component 33 is converted into a temperature display through an electrical signal, which is beneficial for the staff to intuitively understand the temperature of the filter lens 6. On the other hand, in this way, even if the sealing cover 4 is removed, it will not affect the temperature measuring component 33 and the electrical interface 131.

[0040] More preferably, a sealing ring 42 is provided on a side of the sealing cover plate 4 close to the housing 1 .

[0041] Through the above design, the sealing ring 42 can improve the sealing degree between the sealing cover plate 4 and the housing 1, thereby improving the vacuum degree of the vacuum environment inside the housing 1 during testing and also prolonging the duration of the vacuum state.

[0042] More preferably, the first light-transmitting portion 11 is a first optical lens, and the second light-transmitting portion 12 is a second optical lens.

[0043] In this embodiment, the first optical lens and the second optical lens can filter some specific wavelengths of light, so that the staff can control the wavelength of light passing through according to the test conditions, that is, the staff can make adjustments according to different test conditions.

[0044] More preferably, the adsorption component 5 is an activated carbon component, and the activated carbon component is located on the bottom of the housing 1 .

[0045] In this embodiment, the activated carbon component can adsorb the gas between the vacuum-evacuated outer shell 1 and the inner shell 2 through its own adsorption effect, thereby ensuring that the environment of the filter lens 6 is a vacuum environment during the test, making the test environment closer to the actual working environment and improving the accuracy of the test.

[0046] More preferably, the vertical cross-section of the inner shell 2 is in an inverted convex shape, and the light pipe 21 is located at the narrow end of the inverted convex shape.

[0047] The above design is conducive to maintaining the temperature of the narrow end, that is, maintaining the temperature of the filter lens 6. The inverted convex structure can cover the narrow end over a larger area, thereby reducing temperature loss, extending the duration of the low-temperature environment, and reducing the number of times liquid nitrogen is replenished.

[0048] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and purpose of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A dewar for testing the transmittance of optical filters in low-temperature environments, comprising an outer shell and an inner shell, the outer shell being provided with a first light-transmitting portion and a second light-transmitting portion arranged opposite each other, the inner shell being provided with a light pipe, and the inner shell being provided with a fixing mechanism for fixing the optical filter to one end of the light pipe, so that an external light beam can horizontally pass through the first light-transmitting portion, the fixing mechanism, the light pipe, and the second light-transmitting portion in sequence. The invention is characterized in that: The shell forms a closed space inside the shell through a sealing cover plate, and the sealing cover plate is detachably connected to the shell. The first light-transmitting portion is embedded in the shell, and the second light-transmitting portion is arranged on the sealing cover plate. The sealing cover plate is also provided with a closable vacuum port, and the shell is also provided with an adsorption component for maintaining the vacuum degree of the closed space.

2. The transmittance test dewar for optical filters in low temperature environments according to claim 1, characterized in that: The fixing mechanism includes a cold stage and a fixing plate. The cold stage is located on one end of the light tube. The fixing plate is detachably connected to the cold stage. The fixing plate is used to fix the filter lens on the cold stage. The cold stage is provided with a first through hole for the external light beam to pass through. The fixing plate is provided with a second through hole coaxially arranged with the first through hole.

3. The transmittance test dewar for optical filters in low temperature environments according to claim 2, characterized in that: The fixing plate fixes the filter lens on the cold stage by means of a clamping connection, a bolt connection or a magnetic connection; If the fixing plate is connected by clamping, a first clamping member is provided on the cold stage, and a second clamping member is provided on the fixing plate; If the fixing plate is connected by bolts, the fixing plate is provided with a plurality of first screw holes, and the cold stage is provided with second screw holes matching the first screw holes; If the fixing plate is connected by magnetic attraction, the fixing plate is made of magnetic material, the cold stage is made of magnetic material, and a mechanical buffer block is provided between the fixing plate and the filter lens.

4. The transmittance test dewar for optical filters in low temperature environments according to claim 1, characterized in that: The top of the inner shell is provided with a channel for introducing liquid nitrogen, and the channel passes through the outer shell and communicates with the outside; the bottom of the inner shell is provided with a support column, and the support column is connected to the outer shell.

5. The Dewar for testing transmittance of optical filters in low temperature environments according to claim 1, characterized in that: A temperature measuring component is provided on the fixing mechanism.

6. The Dewar for testing transmittance of optical filters in low temperature environments according to claim 5, characterized in that: A horizontal portion extending outward is provided on one side of the housing close to the temperature measuring component. The sealing cover is detachably connected to the horizontal portion. An electrical interface is provided on the horizontal portion. The temperature measuring component is electrically connected to the electrical interface.

7. The Dewar for testing transmittance of optical filters in low temperature environments according to claim 1, characterized in that: A sealing ring is provided on one side of the sealing cover plate close to the shell.

8. The Dewar for testing transmittance of optical filters in low temperature environments according to claim 1, characterized in that: The first light-transmitting portion is a first optical lens, and the second light-transmitting portion is a second optical lens.

9. The Dewar for testing transmittance of optical filters in low temperature environments according to claim 1, characterized in that: The adsorption component is an activated carbon component, and the activated carbon component is located on the bottom of the shell.

10. The Dewar for testing transmittance of optical filters in low temperature environments according to claim 1, characterized in that: The vertical cross section of the inner shell is in an inverted convex shape, and the light pipe is located at the narrow end of the inverted convex shape.

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