High-precision variable-temperature blackbody radiation source based on saturated fluid and temperature control device and method thereof

Abstract

The invention provides a high-precision variable-temperature blackbody radiation source based on saturated fluid and a temperature control device and method thereof, and belongs to the technical field of blackbody radiation sources. The problems that a low-temperature black body of an existing black body radiation source is large in temperature control difficulty and inconvenient to use are solved. According to the technical scheme, the high-precision variable-temperature blackbody radiation source based on the saturated fluid comprises a heat insulation cavity, a blackbody is arranged in the heat insulation cavity, optical glass is arranged on one side of the blackbody, a vacuum interlayer is formed between the blackbody and the optical glass, and the portion, on the other side of the blackbody, in the cavity is filled with the saturated fluid; the method is applied to blackbody radiation source temperature control.

Description

Technical Field

[0001] The invention provides a high-precision variable-temperature blackbody radiation source based on a saturated fluid and a temperature control device and method thereof, belonging to the technical field of blackbody radiation sources. Background Art

[0002] In the performance evaluation of focal plane infrared detectors, high-precision blackbody radiation sources are key equipment, which need to have high temperature stability and temperature certainty to achieve comprehensive performance evaluation of infrared detector chips and components. In practical applications, there is a wide range of application needs for portable large-opening blackbodies. At present, the conventional practice of blackbody radiation sources is to use semiconductor coolers + closed fluids + heating plates; although the temperature uniformity and control accuracy can meet the requirements, the difference between the actual temperature and the objective temperature has not been directly verified on site, resulting in difficulty in controlling the temperature of low-temperature blackbodies used for the evaluation of long-wave and very long-wave infrared detectors, and inconvenience in use. Summary of the invention

[0003] In order to solve the above technical problems, the present invention proposes a high-precision variable-temperature blackbody radiation source based on a saturated fluid and a temperature control device and method thereof.

[0004] The technical solution adopted by the present invention is: a high-precision variable temperature blackbody radiation source based on saturated fluid, including an insulating cavity, in which a blackbody is arranged, and optical glass is arranged on one side of the blackbody so that a vacuum interlayer is formed between the blackbody and the optical glass, and the cavity on the other side of the blackbody is filled with saturated liquid.

[0005] Furthermore, insulation layers are provided on the upper and lower sides of the insulation cavity.

[0006] Furthermore, the optical glass is fully transparent optical glass.

[0007] Furthermore, the black body is a low-temperature black body.

[0008] Furthermore, the isothermal surface temperature range of the low-temperature black body is 0-80°C.

[0009] A temperature control device for a high-precision variable temperature blackbody radiation source based on a saturated fluid comprises a high-precision variable temperature blackbody radiation source based on a saturated fluid, a circulation pump, a liquid temperature control circuit and a precision pressure regulating device. An upper and lower interface is provided on the side of the cavity of an insulating cavity located on the side of the saturated liquid. The upper interface is connected to the circulation pump through a pipeline and then connected to the input end of the liquid temperature control circuit. The output end of the liquid temperature control circuit is connected to a pipeline and then connected to the lower end interface of the saturated liquid through the precision pressure regulating device.

[0010] Furthermore, the liquid temperature control loop includes a semiconductor refrigerator, a heater and a thermometer.

[0011] Furthermore, the precision pressure regulating device is also provided with a pressure gauge.

[0012] Furthermore, the precision pressure regulating device includes a pressure regulating cylinder and a precision feed thread, the movable end of the precision feed thread extends into the pressure regulating cylinder, the movable end of the precision feed thread is provided with a sealing ring, and the free end of the precision feed thread is provided with a handle.

[0013] A temperature control method for a high-precision variable temperature blackbody radiation source based on a saturated fluid, comprising the following steps: S1: Start the circulation pump and the liquid temperature control loop, and perform preliminary temperature control on the saturated liquid through the combination of the semiconductor refrigerator and the heater; S2: Using a precision pressure regulating device, the pressure of the saturated liquid is regulated by adjusting the feed amount of the precision feed thread, thereby achieving precise control of the temperature of the saturated liquid; S3: By controlling the running speed of the circulation pump, the saturated liquid is made to flow at a uniform speed in the chamber, thereby achieving isothermal control of the black body surface.

[0014] Compared with the prior art, the present invention has the following beneficial effects: the present invention utilizes the objective physical law that the temperature of a saturated liquid is strongly correlated with its saturated pressure, and utilizes the saturated pressure of a liquid temperature control circuit to achieve stable and precise control of the temperature on the blackbody side; the temperature control accuracy is high, and the device has its own thermometer for calibration. Through a low-speed circulating pump, the blackbody surface has continuous fluid convection heat exchange, thereby improving the surface temperature uniformity of the blackbody isothermal surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described below in conjunction with the accompanying drawings: Figure 1 A schematic diagram of the structure of testing an infrared detector assembly using the variable temperature black body radiation source and the temperature control device thereof of the present invention; Figure 2 It is a structural schematic diagram of a precision voltage regulating device; In the figure: 1 is the pressure adjustment cylinder, 2 is the sealing ring, and 3 is the precision feed thread. DETAILED DESCRIPTION

[0016] like Figure 1 and 2As shown, the present invention provides a high-precision variable-temperature blackbody radiation source based on a saturated fluid, including a low-temperature blackbody, and a fully transparent optical glass is installed on the front side of the blackbody, so that a vacuum interlayer is formed between the isothermal surface of the blackbody and the glass to prevent condensation, and the arrangement of the glass can achieve isolation of the blackbody from the outside world, and the glass can dissipate heat, thereby achieving heat exchange between the inside and the outside; the closed cavity on the rear side of the blackbody is filled with a saturated liquid, and the saturated liquid and the isothermal surface of the low-temperature blackbody are insulated and packaged; insulation layers are arranged on the upper and lower sides of the blackbody, and the insulation layers are used to isolate the vacuum interlayer, the blackbody and the saturated liquid from the upper and lower external environments.

[0017] Saturated liquid refers to a state where liquid and vapor are in dynamic equilibrium. At this time, the temperature of the gas and liquid is the same, which is called the saturation temperature, and the corresponding vapor pressure is called the saturation pressure. In the saturated state, the evaporation rate of the liquid is equal to the condensation rate of the vapor, so that the amount of gas and liquid remains unchanged, reaching a stable equilibrium state. The properties of a saturated liquid are: 1. Relationship between temperature and pressure: The temperature and pressure of saturated liquid correspond to each other, that is, a certain saturation temperature corresponds to a certain saturation pressure. When the temperature rises, the vaporization speed increases, and the vapor density in the space also increases until the dynamic equilibrium is re-established.

[0018] 2. Dynamic equilibrium: In the saturated state, the amount of liquid and vapor remains unchanged, and the gas and liquid are in equilibrium. This state is called saturated state, and the liquid at this time is called saturated liquid.

[0019] 3. Boiling phenomenon: If the pressure on a liquid is less than the saturation pressure corresponding to its temperature, vaporization will occur inside the liquid, forming bubbles that rise to the surface and explode. This violent vaporization process is called boiling.

[0020] Based on the above principle, the present invention can achieve precise adjustment of the black body surface temperature by adjusting the pressure of the saturated liquid, and further proposes a temperature control device based on a high-precision variable temperature black body radiation source of a saturated fluid. On the basis of the structure of the above black body radiation source, two interfaces are respectively opened on the upper and lower sides of the cavity on one side of the saturated liquid. The upper interface is connected to the circulation pump through a pipeline and then connected to the input end of the liquid temperature control loop for preliminary temperature control. A pipeline is connected from the output end of the liquid temperature control loop, and then connected back to the lower end interface of the saturated liquid through a precise pressure regulating device.

[0021] The liquid temperature control circuit includes a semiconductor refrigerator, a heater and a thermometer, and preliminary temperature control of the saturated liquid can be achieved through the semiconductor refrigerator and the heater.

[0022] The present invention adopts a low-speed circulating pump to achieve isothermal control of the black body surface.

[0023] like Figure 2 As shown, the precision pressure regulating device can accurately regulate the pressure of the saturated liquid. The precision pressure regulating device includes a pressure regulating cylinder 1 and a precision feed thread 2. The movable end of the precision feed thread 2 extends into the pressure regulating cylinder, and a sealing ring is provided at the movable end of the precision feed thread 2. A handle is provided at the free end of the precision feed thread 2, which is convenient for manual operation. Due to the setting accuracy of the precision feed thread, the accuracy of pressure regulation can be guaranteed. A pressure gauge is also provided on the precision pressure regulating device, and the real-time pressure value can be displayed through the pressure gauge.

[0024] And due to the above-mentioned characteristics of the saturated liquid, when the present invention is in use, the current temperature value of the saturated liquid can be obtained by a table lookup method based on the value of the pressure gauge on the precision pressure regulating device. The temperature value is an absolute temperature. Through the absolute temperature, the thermometer on the liquid temperature control circuit can also be self-calibrated, which is convenient, fast, time-saving and labor-saving, and also improves the use efficiency of the equipment.

[0025] Based on the above temperature control device, accurate temperature adjustment of the black body radiation source can be achieved. The specific adjustment steps are as follows: S1: Start the circulation pump and the liquid temperature control loop, and perform preliminary temperature control on the saturated liquid through the combination of the semiconductor refrigerator and the heater; S2: Using the precision pressure regulating device, the pressure of the saturated liquid is regulated by manually adjusting the feed amount of the precision feed thread 2, thereby achieving precise control of the temperature of the saturated liquid; S3: By controlling the running speed of the circulation pump, the saturated liquid is made to flow at a uniform speed in the chamber, thereby achieving isothermal control of the black body surface.

[0026] Through the above-mentioned device and method, the present invention can realize accurate adjustment of the temperature range of 0-80°C of the black body isothermal surface, meeting the test requirements of the focal plane infrared detector.

[0027] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-precision variable temperature blackbody radiation source based on saturated fluid, characterized by: The invention comprises an insulating cavity, in which a black body is arranged, and optical glass is arranged on one side of the black body, so that a vacuum interlayer is formed between the black body and the optical glass, and the cavity on the other side of the black body is filled with saturated liquid.

2. A high-precision variable temperature blackbody radiation source based on saturated fluid according to claim 1, characterized in that: Insulation layers are arranged on the upper and lower sides of the insulation cavity.

3. A high-precision variable temperature blackbody radiation source based on saturated fluid according to claim 1, characterized in that: The optical glass is fully transparent optical glass.

4. A high-precision variable temperature blackbody radiation source based on a saturated fluid according to any one of claims 1 to 3, characterized in that: The black body adopts a low-temperature black body.

5. A high-precision variable temperature blackbody radiation source based on saturated fluid according to claim 4, characterized in that: The isothermal surface temperature range of the low-temperature black body is 0-80°C.

6. A temperature control device for a high-precision variable temperature blackbody radiation source based on a saturated fluid, characterized in that: It comprises a high-precision variable temperature blackbody radiation source based on a saturated fluid as described in any one of claims 1 to 5, and also comprises a circulation pump, a liquid temperature control circuit and a precision pressure regulating device. An upper and lower interface is provided on the side of the cavity body of the insulation cavity located on the side of the saturated liquid. The upper interface is connected to the circulation pump through a pipeline and then connected to the input end of the liquid temperature control circuit. The output end of the liquid temperature control circuit is connected to a pipeline and then connected to the lower end interface of the saturated liquid through the precision pressure regulating device.

7. The temperature control device of a high-precision variable temperature blackbody radiation source based on a saturated fluid according to claim 6, characterized in that: The liquid temperature control loop includes a semiconductor refrigerator, a heater and a thermometer.

8. The temperature control device of a high-precision variable temperature blackbody radiation source based on a saturated fluid according to claim 6, characterized in that: The precise pressure regulating device is also provided with a pressure gauge.

9. The temperature control device of a high-precision variable temperature blackbody radiation source based on a saturated fluid according to claim 8, characterized in that: The precision pressure regulating device comprises a pressure regulating cylinder and a precision feed thread, the movable end of the precision feed thread extends into the pressure regulating cylinder, the movable end of the precision feed thread is provided with a sealing ring, and the free end of the precision feed thread is provided with a handle.

10. A method for controlling the temperature of a blackbody by using the temperature control device of a high-precision variable temperature blackbody radiation source based on a saturated fluid as claimed in any one of claims 6 to 9, characterized in that: The following steps are involved: S1: Start the circulation pump and the liquid temperature control loop, and perform preliminary temperature control on the saturated liquid through the combination of the semiconductor refrigerator and the heater; S2: Using a precision pressure regulating device, the pressure of the saturated liquid is regulated by adjusting the feed amount of the precision feed thread, thereby achieving precise control of the temperature of the saturated liquid; S3: By controlling the running speed of the circulation pump, the saturated liquid is made to flow at a uniform speed in the chamber, thereby achieving isothermal control of the black body surface.

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