Observator temperature control method based on mixed mode

Abstract

The invention relates to an observation instrument temperature control method based on a mixed mode, belongs to the technical field of refrigeration of refrigeration type observation instruments, and solves the problem that in the prior art, a refrigeration type observation instrument is poor in refrigeration effect in a complex temperature environment. The observation instrument temperature control method comprises the steps that the external environment temperature of a refrigeration type observation instrument is acquired, and the working mode of the refrigeration type observation instrument is determined according to the external environment temperature; the working modes comprise a low-temperature mode and a high-temperature mode; and determining the driving current of the TEC and / or the excitation voltage of the quantum dot coating according to the working mode of the refrigeration type observation instrument so as to control the temperature of the TEC. And the refrigeration effect of the observation instrument in a complex temperature environment is improved.

Description

Technical Field

[0001] This invention relates to the field of cooling technology for refrigerated observation instruments, and more particularly to a temperature control method for observation instruments based on a hybrid mode. Background Technology

[0002] Cooled infrared imaging devices play a crucial role in industrial inspection, security monitoring, and scientific research. Their core advantage lies in significantly reducing detector noise through low-temperature operation, thereby improving image resolution and detection sensitivity. Compared to uncooled infrared imaging devices, these devices perform particularly well in long-distance observation and low-contrast scenarios, providing clearer imaging results.

[0003] However, existing refrigeration technologies mainly rely on the electrothermal conversion principle of TEC (Thermoelectric cooler), which can maintain basic performance under stable temperature conditions, but exposes a series of limitations when faced with complex temperature fluctuations common in the field or industrial sites.

[0004] Specifically, when the instrument is deployed in an environment with drastic temperature changes (such as large diurnal temperature range or seasonal climate changes), the cooling efficiency of the TEC (Cooling Technology Controller) will decrease significantly due to Seebeck effect attenuation and insufficient heat dissipation at the hot end. In existing technologies, the drive control of the TEC mostly adopts a fixed current mode, which cannot dynamically adapt to changes in external temperature, leading to uncontrolled cold end temperature; especially when the ambient temperature exceeds 40°C, the cooling coefficient can decrease by more than 40%, causing degradation of the instrument's imaging quality.

[0005] In addition, traditional methods lack the utilization of the photothermal synergy effect and rely solely on a single electrothermal conversion mechanism, making it difficult to cope with interference from external heat loads such as solar radiation, which reduces the reliability of the observation instrument under high temperature and high humidity conditions.

[0006] A deeper problem lies in the fact that existing temperature control schemes do not adequately consider the adaptive switching of operating modes. For example, in low-temperature environments, the TEC may over-cool, increasing energy consumption; in high-temperature environments, insufficient heat dissipation may lead to overheating of the hot end. This rigid control strategy not only limits the application range of the instrument in complex environments but also increases the risk of equipment failure. Although some studies have attempted to optimize TEC performance by improving heat sinks or fans, these measures have failed to fundamentally solve the core problem of temperature adaptive control.

[0007] Therefore, there is an urgent need for a method to improve the robustness and energy efficiency of cooled observation instruments in environments with fluctuating temperatures. Summary of the Invention

[0008] Based on the above analysis, the present invention aims to provide a hybrid mode-based temperature control method for observation instruments to solve the problem of poor cooling effect of existing cooled observation instruments in complex temperature environments.

[0009] This invention provides a hybrid-mode-based instrument temperature control method, the instrument temperature control method comprising:

[0010] The external ambient temperature of the cooled observation instrument is obtained, and the operating mode of the cooled observation instrument is determined based on the external ambient temperature; the operating modes include low temperature mode and high temperature mode.

[0011] The driving current of the TEC and / or the excitation voltage of the quantum dot coating are determined according to the operating mode of the cooled observation instrument to control the temperature of the TEC.

[0012] Based on a further improvement to the above-mentioned temperature control method for the observation instrument, the step of determining the operating mode of the cooling observation instrument according to the external ambient temperature includes:

[0013] Determine if the external ambient temperature is greater than the mode switching temperature threshold;

[0014] If the ambient temperature is higher than the mode switching temperature threshold, the cooling observation instrument will switch to high temperature mode.

[0015] Otherwise, the cooling observation instrument switches to low-temperature mode.

[0016] Based on the further improvement of the above-mentioned temperature control method for the observation instrument, when the operating mode of the cooled observation instrument is low temperature mode, the temperature of the TEC is controlled through the following steps:

[0017] Obtain the real-time cold junction temperature of the TEC and determine the real-time cold junction temperature difference by combining it with the target cold junction temperature.

[0018] Determine if the real-time temperature difference of the cold junction exceeds the temperature difference threshold; if the real-time temperature difference of the cold junction exceeds the temperature difference threshold, switch the operating mode of the cooling observation instrument from low temperature mode to high temperature mode; otherwise, use the rated drive current of the TEC to achieve temperature control of the TEC.

[0019] Based on further improvements to the above-mentioned temperature control method for the observation instrument, when the operating mode of the cooled observation instrument is high-temperature mode, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined through the following steps to control the temperature of the TEC:

[0020] The wavelengths of the internal light source and the external ambient light of the cooled observation instrument are obtained, as well as the real-time temperatures of the cold end and hot end of the TEC; the cold end surface of the TEC is coated with a quantum dot coating.

[0021] The real-time temperature of the hot end is compared with the first threshold temperature and the second threshold temperature to obtain the hot end temperature comparison result.

[0022] Based on the comparison results of the hot end temperature, combined with the wavelength of the internal light source, the wavelength of the external ambient light, the real-time temperature of the cold end of the TEC, and the target cooling temperature of the cold end, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined to control the temperature of the TEC.

[0023] Based on further improvements to the above-mentioned temperature control method for the observation instrument, the hot-end temperature comparison results include:

[0024] The real-time temperature of the hot end is less than or equal to the first threshold temperature;

[0025] The real-time temperature of the hot end is greater than the first threshold temperature and less than or equal to the second threshold temperature;

[0026] The real-time temperature of the hot end is greater than the second threshold temperature.

[0027] Based on further improvements to the above-mentioned temperature control method for the observation instrument, when the hot-end temperature comparison result shows that the real-time hot-end temperature is less than or equal to the first threshold temperature, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined through the following steps:

[0028] Determine whether the wavelength of the internal light source is within the inherent excitation wavelength range of the quantum dot coating;

[0029] When the wavelength of the internal light source is within the inherent excitation wavelength range of the quantum dot coating, the following steps are performed:

[0030] The wavelength matching degree is determined based on the wavelength of the external ambient light and the inherent excitation wavelength of the quantum dot coating, and the temperature difference weight is determined based on the real-time cold end temperature of the TEC and the target cooling temperature of the cold end.

[0031] The excitation voltage of the quantum dot coating is determined based on wavelength matching degree and temperature difference weighting.

[0032] The driving current of the TEC is determined based on the excitation voltage of the quantum dot coating and the internal resistance of the TEC.

[0033] Based on further improvements to the above-mentioned temperature control method for the observation instrument, the wavelength matching degree is determined using the following formula:

[0034]

[0035] Where α represents the wavelength matching degree, λ env λ represents the wavelength of ambient light. qd This indicates the inherent excitation wavelength of the quantum dot coating;

[0036] The temperature difference weight is determined using the following formula:

[0037]

[0038] Where β represents the temperature difference weight, T cold T represents the real-time cold junction temperature of the TEC. target This indicates the target cooling temperature at the cold end.

[0039] Based on further improvements to the temperature control method of the aforementioned observation instrument, the excitation voltage of the quantum dot coating is determined using the following formula:

[0040] V qd =k1·α+k2·β·T target ;

[0041] Among them, V qd The excitation voltage of the quantum dot coating is represented by k1 and k2, which represent the first calibration coefficient and the second calibration coefficient, respectively.

[0042] The drive current of the TEC is determined by the following formula:

[0043]

[0044] Among them, I TEC R represents the drive current of the TEC. TEC This indicates the internal resistance of the TEC.

[0045] Based on the further improvement of the above-mentioned temperature control method of the observation instrument, when the hot end temperature comparison result is that the real-time temperature of the hot end is greater than the first threshold temperature and less than or equal to the second threshold temperature, the hot end of the TEC is cooled down by reducing the driving current of the TEC.

[0046] The drive current of the TEC is updated using the following formula:

[0047] I TEC =I′ TEC -k3·(T hot -T1);

[0048] Among them, I′ TEC I represents the drive current of the TEC before the update. TEC This represents the updated TEC drive current, k3 represents the current regulation coefficient, and T... hot T1 represents the real-time hot end temperature of the TEC, and T1 represents the first threshold temperature.

[0049] Based on the further improvement of the temperature control method of the above-mentioned observation instrument, when the hot end temperature comparison result shows that the real-time temperature of the hot end is greater than the second threshold temperature, the power supply of the TEC is cut off and an alarm is triggered.

[0050] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0051] 1. The operating mode of the cooling observation instrument can be flexibly adjusted according to the external ambient temperature. At the same time, the driving current of the TEC and / or the excitation voltage of the quantum dot coating are determined in high temperature mode and low temperature mode respectively to control the temperature of the TEC, thereby improving the cooling effect of the observation instrument in complex temperature environments.

[0052] 2. By utilizing the internal light source wavelength, external ambient light wavelength, real-time cold junction temperature of the TEC, and target cooling temperature of the cold junction in high-temperature mode, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined in real time, thereby achieving real-time control of the cold junction temperature of the TEC and ensuring the cooling effect of the cooling observation instrument.

[0053] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0054] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0055] Figure 1 A schematic diagram of a quantum dot-enhanced cooled observation instrument provided for an embodiment of the present invention;

[0056] Figure 2 A schematic flowchart of a hybrid mode-based temperature control method for an observation instrument provided in an embodiment of the present invention;

[0057] Figure 3 This is a schematic diagram of a process for determining the driving current of a TEC and the excitation voltage of a quantum dot coating, provided as an embodiment of the present invention. Detailed Implementation

[0058] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0059] One specific embodiment of the present invention discloses a quantum dot-enhanced cooled observation instrument, such as... Figure 1 As shown, the cooled observation instrument includes:

[0060] The cold end surface of TEC is coated with a quantum dot coating;

[0061] A spectral sensor is used to acquire the wavelengths of the internal light source and the external ambient light of the cooled observation instrument and transmit them to the temperature control module.

[0062] The first temperature sensor is used to acquire the real-time cold end temperature of the TEC and transmit it to the temperature control module.

[0063] The second temperature sensor is used to acquire the real-time temperature of the hot end of the TEC and transmit it to the temperature control module.

[0064] The third temperature sensor is used to acquire the external ambient temperature of the cooled observation instrument and transmit it to the temperature control module.

[0065] A temperature control module is used to determine the drive current of the TEC and / or the excitation voltage of the quantum dot coating to control the cold junction temperature of the TEC.

[0066] Specifically, existing cooled observation instruments rely on a TEC (thermal energy conversion system) for cooling during operation. The TEC depends solely on electro-thermal conversion. In the field environment, solar radiation (especially in the near-infrared band) exacerbates the heat load of the cooled observation instrument. When the ambient temperature is above 40°C, the coefficient of performance of the existing TEC decreases by more than 40% due to the weakening Seebeck effect and the reduced heat dissipation efficiency at the hot end. This leads to the failure of temperature control in the cooled observation instrument, resulting in a significant decrease in the measurement accuracy of the cooled observation instrument.

[0067] Specifically, a TEC (Cooling Component) is a cooling element made of semiconductor materials. It has two surfaces with completely opposite functions: a cold end and a hot end. When energized, the cold end absorbs heat and its temperature continuously decreases, ultimately achieving cooling. When energized, the heat absorbed by the cold end is transferred to the hot end surface, causing the hot end temperature to rise. In practical applications, the hot end needs to be equipped with a cooling fan, heat sink, etc., to quickly dissipate the heat to the external environment; otherwise, overheating of the hot end will directly lead to cooling failure.

[0068] like Figure 1 As shown, the cooling observation instrument provided in this embodiment of the invention has a quantum dot coating on the cold end of the TEC. The excitation voltage of the quantum dot coating is set by the temperature control module, which causes the cold end temperature of the TEC to drop, so that the cold end temperature of the TEC is controlled near the target cooling temperature of the cold end.

[0069] It is worth noting that the quantum dot coating applied to the cold end of the TEC in this embodiment of the invention is used to enhance the cooling effect of the cold end, not to dissipate heat at the hot end. The quantum dot coating can absorb ambient light energy and convert it into weak electrical energy or directly assist in heat transfer by matching the wavelength of ambient light, reducing the "backflow" of heat at the cold end. The cold end is the "output end" of the cooling function. Coating its surface with quantum dots can directly form a "light-heat-electricity synergy" with the cooling effect of the TEC, improving the cooling efficiency from the source.

[0070] In a specific example, TEC uses the TEC1-12706 type semiconductor cooling chip, with a cold end surface size of 20×20mm. The cold end surface is sandblasted to enhance coating adhesion, and the hot end integrates a miniature aluminum heat sink with a height of 5mm and a spacing of 2mm.

[0071] Preferably, a composite layer of indium foil and nano-alumina powder is laid on the cold end surface of the TEC, and a quantum dot coating is applied to the composite layer.

[0072] Specifically, the contact thermal resistance is reduced by using a composite layer, resulting in a contact thermal resistance ≤ 0.01 K·m. 2 / W, the composite layer is 0.05mm thick to solve the problem of thermal expansion mismatch between TEC and heat pipe array, and improve the effect of cold end temperature transfer.

[0073] In a specific example, a 0.05mm indium foil and nano-Al2O3 powder composite layer is laid between the cold end surface of the TEC and the quantum dot coating, with the mass ratio of indium foil to nano-Al2O3 being 1:9. This is achieved through hot pressing under 10MPa pressure, resulting in a contact thermal resistance ≤0.01K·m. 2 / W.

[0074] Preferably, the quantum dots in the quantum dot coating are cadmium telluride quantum dots.

[0075] In a specific example, cadmium telluride quantum dots were dispersed and mixed with PVP solution at a mass ratio of 1:18, and ultrasonically dispersed until the particle size distribution was uniform, forming a colloid with a mass concentration of 6%. The colloid was sprayed in two layers onto the cold end surface of the TEC. The first layer was sprayed 15 cm away from the cold end, forming a continuous film layer of 15 ± 2 μm. After standing for 5 minutes to evaporate the ethanol solvent, the second layer was sprayed 10 cm away from the cold end, forming an enhancement layer of 65 ± 2 μm, for a total thickness of 80 ± 2 μm. The colloid was heated to 80 °C at a rate of 2 °C / min in a nitrogen atmosphere and held for 30 minutes to form a dense cadmium telluride quantum dot coating with a surface roughness Ra ≤ 1.5 μm and a thermal conductivity of 1.2 W / (m·K).

[0076] Preferably, the particle size of the quantum dots in the quantum dot coating is in the range of 3-5 nm;

[0077] The thickness of the quantum dot coating is 50-100 μm.

[0078] Specifically, by coating the cold end of the TEC with a cadmium telluride quantum dot coating with a particle size of 3-5nm, and dynamically adjusting the quantum dot excitation voltage based on the ambient light wavelength, a synergistic cooling effect of light, heat, and electricity is achieved. The excitation voltage range of the cadmium telluride quantum dot coating is 0-5V. After the temperature control module generates the excitation voltage of the quantum dot coating, it needs to be matched with the excitation voltage range of the quantum dot coating. Only if the match is successful can the process be executed; if the match fails, the process cannot be executed.

[0079] Preferably, such as Figure 1 As shown, the ratio of the surface area of ​​the quantum dot coating to the cold end surface area of ​​the TEC ranges from 0.9 to 1.

[0080] Specifically, the ratio of the surface area of ​​the quantum dot coating to the surface area of ​​the cold end of the TEC is set to 0.9-1 to ensure that the photothermal conversion area covers the cold end of the TEC, thereby improving the temperature transfer effect.

[0081] Specifically, such as Figure 1 As shown, the spectral sensor provided in this embodiment of the invention is used to acquire the wavelength of the light source inside the cooled observation instrument on the one hand, and to acquire the ambient wavelength outside the cooled observation instrument on the other hand, and transmits the acquired information of the internal light source wavelength and the external ambient wavelength to the temperature control module.

[0082] Preferably, the spectral sensor has a detection wavelength range of 400–1100 nm, a resolution of 5 nm, and a sampling frequency of 10 Hz.

[0083] In a specific example, the spectral sensor used is a Hamamatsu C13534-32 spectral sensor with a detection wavelength range of 400-1100nm, a resolution of 5nm, and real-time sampling of ambient light (such as sunlight and industrial light sources) at 10Hz, as well as the built-in LED light source of the observer (center wavelength 940nm).

[0084] Specifically, such as Figure 1 As shown, the first temperature sensor provided in this embodiment of the invention is used to acquire the temperature of the cold end of the TEC in real time and transmit the real-time temperature of the cold end to the temperature control module.

[0085] In a specific example, the first temperature sensor is a DS18B20 temperature sensor with an accuracy of ±0.5℃, which collects the cold junction temperature of the TEC in real time.

[0086] In a specific example, the second temperature sensor is a DS18B20 temperature sensor with an accuracy of ±0.5℃, which collects the hot end temperature of the TEC in real time and transmits it to the temperature control module.

[0087] Specifically, such as Figure 1 As shown, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined in the temperature control module.

[0088] In a specific example, the temperature control module uses an FPGA controller, for example a Xilinx Artix-7 XC7A100T, which integrates a high-speed ADC interface and a PWM generator, with a processing delay of ≤10ms. The Xilinx Artix-7XC7A100T is used to determine the excitation voltage of the quantum dot coating and the drive current of the TEC.

[0089] Another specific embodiment of the present invention discloses a temperature control method for an observation instrument based on a hybrid mode, through... Figure 1 The temperature control module in the middle executes the operation, such as Figure 2 As shown, the temperature control method of the observation instrument includes:

[0090] Step S1: Obtain the external ambient temperature of the cooled observation instrument and determine the operating mode of the cooled observation instrument based on the external ambient temperature; the operating modes include low temperature mode and high temperature mode.

[0091] Step S2: Determine the driving current of the TEC and / or the excitation voltage of the quantum dot coating according to the operating mode of the cooled observation instrument to control the temperature of the TEC.

[0092] Specifically, such as Figure 1 As shown, in step S1, the external ambient temperature of the cooled observation instrument is received from the third temperature sensor, and the operating mode of the cooled observation instrument is determined to be either high temperature mode or low temperature mode based on the external ambient temperature of the cooled observation instrument.

[0093] Preferably, determining the operating mode of the cooling observation instrument based on the external ambient temperature includes:

[0094] Determine if the external ambient temperature is greater than the mode switching temperature threshold;

[0095] If the ambient temperature is higher than the mode switching temperature threshold, the cooling observation instrument will switch to high temperature mode.

[0096] Otherwise, the cooling observation instrument switches to low-temperature mode.

[0097] Specifically, the external ambient temperature is compared with a pre-set mode switching temperature threshold, and the operating mode of the cooling observation instrument is determined based on the comparison result.

[0098] Preferably, the mode switching temperature threshold is set to 40°C.

[0099] Specifically, when the ambient temperature is greater than 40°C, the cooling observation instrument switches to high-temperature mode; when the ambient temperature is less than or equal to 40°C, the cooling observation instrument switches to low-temperature mode.

[0100] Specifically, such as Figure 2 As shown, in step S2, the driving current of the TEC and / or the excitation voltage of the quantum dot coating are determined according to the operating mode of the cooled observation instrument.

[0101] Preferably, when the operating mode of the cooled observation instrument is low temperature mode, the temperature of the TEC is controlled by the following steps:

[0102] Obtain the real-time cold junction temperature of the TEC and determine the real-time cold junction temperature difference by combining it with the target cold junction temperature.

[0103] Determine if the real-time temperature difference of the cold junction exceeds the temperature difference threshold; if the real-time temperature difference of the cold junction exceeds the temperature difference threshold, switch the operating mode of the cooling observation instrument from low temperature mode to high temperature mode; otherwise, use the rated drive current of the TEC to achieve temperature control of the TEC.

[0104] Specifically, when the cooling observation instrument is in low-temperature mode, the external ambient temperature is lower than the mode switching temperature threshold. At this time, the operating mode of the cooling observation instrument is flexibly adjusted according to the real-time difference of the cold end temperature.

[0105] When the real-time temperature difference of the cold end is greater than the temperature difference threshold, it indicates that the real-time temperature of the cold end is significantly different from the target cooling temperature of the cold end. In this case, the operation of the cooling observation instrument can be switched from low temperature mode to high temperature mode to improve the cooling effect. When the real-time temperature difference of the cold end is less than or equal to the temperature difference threshold, it indicates that the real-time temperature of the cold end is not significantly different from the target cooling temperature of the cold end. In this case, only the low temperature mode needs to be used, that is, the temperature control of the TEC is achieved by using the rated drive current of the TEC.

[0106] Preferably, the temperature difference threshold is set to 5°C.

[0107] When the real-time temperature difference between the cold end and the high end exceeds 5°C, the operation of the cooling observation instrument will be switched from low-temperature mode to high-temperature mode; otherwise, the low-temperature mode will be used to control the temperature of the TEC.

[0108] Preferably, when the operating mode of the cooled observation instrument is high-temperature mode, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined by the following steps to control the temperature of the TEC:

[0109] Step S31: Obtain the wavelength of the internal light source and the wavelength of the external ambient light of the cooled observation instrument, and obtain the real-time temperature of the cold end and the real-time temperature of the hot end of the TEC; wherein, the cold end surface of the TEC is coated with a quantum dot coating.

[0110] Step S32: Compare the real-time temperature of the hot end with the first threshold temperature and the second threshold temperature to obtain the hot end temperature comparison result;

[0111] Step S33: Based on the hot end temperature comparison results, combined with the internal light source wavelength, external ambient light wavelength, TEC cold end real-time temperature and cold end target cooling temperature, determine the TEC driving current and quantum dot coating excitation voltage to control the TEC temperature.

[0112] Specifically, such as Figure 3As shown, in step S31, the real-time cold end temperature and the real-time hot end temperature of the TEC are obtained through the first temperature sensor and the second temperature sensor, and the wavelength of the internal light source and the wavelength of the external ambient light of the cooling observation instrument are obtained through the spectral sensor.

[0113] Specifically, such as Figure 3 As shown, in step S32, the real-time temperature of the hot end is compared with the first threshold temperature and the second threshold temperature.

[0114] Preferably, the hot-end temperature comparison results include:

[0115] The real-time temperature of the hot end is less than or equal to the first threshold temperature;

[0116] The real-time temperature of the hot end is greater than the first threshold temperature and less than or equal to the second threshold temperature;

[0117] The real-time temperature of the hot end is greater than the second threshold temperature.

[0118] Specifically, the second threshold temperature is greater than the first threshold temperature. For example, the first threshold temperature is 60°C and the second threshold temperature is 80°C. The real-time temperature of the hot end is compared with the first threshold temperature and the second threshold temperature to determine the comparison result of the hot end temperature.

[0119] Specifically, such as Figure 3 As shown, based on the hot end temperature comparison results obtained in step S32, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined in step S33 to control the temperature of the TEC.

[0120] Preferably, when the hot-end temperature comparison result shows that the real-time hot-end temperature is less than or equal to the first threshold temperature, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined through the following steps:

[0121] Determine whether the wavelength of the internal light source is within the inherent excitation wavelength range of the quantum dot coating;

[0122] When the wavelength of the internal light source is within the inherent excitation wavelength range of the quantum dot coating, the following steps are performed:

[0123] The wavelength matching degree is determined based on the wavelength of the external ambient light and the inherent excitation wavelength of the quantum dot coating, and the temperature difference weight is determined based on the real-time cold end temperature of the TEC and the target cooling temperature of the cold end.

[0124] The excitation voltage of the quantum dot coating is determined based on wavelength matching degree and temperature difference weighting.

[0125] The driving current of the TEC is determined based on the excitation voltage of the quantum dot coating and the internal resistance of the TEC.

[0126] Specifically, the inherent excitation wavelength of the quantum dot coating is related to the material of the quantum dot coating. For example, if the inherent excitation wavelength of cadmium telluride quantum dots is 980 nm, then the inherent excitation wavelength range of the cadmium telluride quantum dot layer can be set to 980 ± 10 nm.

[0127] It is understandable that when the wavelength of the internal light source is within the inherent excitation wavelength range of the quantum dot coating, the quantum dot coating can absorb heat. By determining whether the wavelength of the internal light source is within the inherent excitation wavelength range of the quantum dot coating, it can be determined whether to generate an excitation voltage for the quantum dot coating to achieve cooling.

[0128] Specifically, when the wavelength of the internal light source is within the inherent excitation wavelength range of the quantum dot coating, the temperature control module determines the driving current of the TEC and the excitation voltage of the quantum dot coating based on the wavelength of the external ambient light, the real-time temperature of the cold end of the TEC, and the target cooling temperature of the cold end.

[0129] It is worth noting that when the wavelength of the internal light source is not within the inherent excitation wavelength range of the quantum dot coating, the cooling effect through the quantum dot coating is difficult to guarantee, and cooling is no longer achieved through the quantum dot coating in this case.

[0130] Specifically, the wavelength matching degree is determined based on the wavelength of the external ambient light and the inherent excitation wavelength of the quantum dot coating.

[0131] Preferably, the wavelength matching degree is determined by the following formula:

[0132]

[0133] Where α represents the wavelength matching degree, λ env λ represents the wavelength of ambient light. qd This indicates the inherent excitation wavelength of the quantum dot coating.

[0134] It is worth noting that wavelength matching degree α can be used to determine the optical compatibility of quantum dot excitation.

[0135] When α≈0, that is, the wavelength of the external ambient light λ env Equal to the intrinsic excitation wavelength λ of the quantum dot coating qd , such as λ env =980nm, λ qd =980nm, the ambient light and the excitation wavelength of quantum dots are highly matched, and quantum dots can efficiently absorb light energy and assist in cooling without high voltage.

[0136] When α is large, such as λ env =800nm, λ qd=980nm, α≈0.18, the ambient light and the quantum dot excitation wavelength deviate greatly, and the quantum dot photo-thermal conversion efficiency is low. At this time, it is necessary to compensate for the loss of cooling effect caused by the wavelength deviation to ensure that the photo-thermal synergy does not fail.

[0137] Specifically, the temperature difference weight is determined based on the real-time cold end temperature of the TEC and the target cooling temperature of the cold end.

[0138] Preferably, the temperature difference weight is determined by the following formula:

[0139]

[0140] Where β represents the temperature difference weight, T cold T represents the real-time cold junction temperature of the TEC. target This indicates the target cooling temperature at the cold end.

[0141] It is worth noting that the temperature difference weight β is used to determine the relative proportion of the temperature difference and the target cooling temperature at the cold end during refrigeration, quantify the deviation proportion between the actual temperature at the cold end and the target cooling temperature at the cold end, and determine whether it is necessary to prioritize increasing the cooling intensity.

[0142] When β is large, such as T target = -10℃, T cold =0℃, β=-1, the real-time temperature of the cold end is much higher than the target cooling temperature of the cold end, the temperature difference accounts for 100% of the target temperature, the cooling demand is urgent, and it is necessary to speed up the cooling speed of the cold end.

[0143] When β≈0, such as T cold = -9.5℃, T target = -10℃, β = -0.05, the real-time temperature of the cold end is close to the target cooling temperature of the cold end, the temperature difference is only 5% of the target temperature, the cooling demand is moderate, and the temperature can be maintained stably.

[0144] Specifically, the excitation voltage of the quantum dot coating is determined based on wavelength matching and temperature difference weighting.

[0145] Preferably, the excitation voltage of the quantum dot coating is determined by the following formula:

[0146] V qd =k1·α+k2·β·T target

[0147] Among them, V qd The excitation voltage of the quantum dot coating is represented by k1 and k2, which represent the first calibration coefficient and the second calibration coefficient, respectively.

[0148] Specifically, k1 and k2 can be calibrated through multiple sets of controlled variable experiments. Before calibration, it is necessary to ensure that other parameters are unique, including:

[0149] The ambient temperature is fixed, for example, 40℃;

[0150] The module parameters of TEC are fixed, such as the internal resistance R of TEC. TEC The surface area of ​​the cold end is fixed;

[0151] The quantum dot coating parameters are fixed, such as the particle size of cadmium telluride quantum dots being 3-5 nm, the coating thickness being 50-100 μm, and the ratio of the surface area of ​​the quantum dot coating to the surface area of ​​the cold end being 0.95.

[0152] Target cooling temperature T target Fixed, such as the typical low temperature required by the observation instrument, such as -10°C or 0°C).

[0153] Experimental testing procedure:

[0154] Step 1: Calibrate k1 (ambient light wavelength versus V) qd (influence coefficient).

[0155] The temperature difference is fixed at 0, i.e., T cold =T target Change the dominant wavelength λ of ambient light env The detection range of the spectral sensor is 400-1100 nm, with a focus on testing the region near the intrinsic excitation wavelength of quantum dots, 970-990 nm. For each λ... env Adjust V qd Quantum dots have the highest light-to-heat conversion efficiency, i.e., T cold Stable and with the lowest TEC power consumption, record the corresponding V. qd The value is calculated by linear fitting, and k1 is obtained.

[0156] Step 2: Calibrate k2 (temperature difference versus V) qd (Influence coefficient)

[0157] Fixed λ env =λ qd That is, matching the ambient light wavelength with the inherent excitation wavelength of the quantum dot, and changing T cold This covers the temperature difference range that the observation instrument actually needs for cooling, for each T cold Adjust V qd The cold end temperature stabilizes to T the fastest. target Record the corresponding V qd The value is calculated by linear fitting, and k2 is obtained.

[0158] Step 3: Coefficient verification and correction to ensure compliance with performance indicators.

[0159] Substitute the calibrated k1 and k2 into the complete formula (V) qd =k1·α+k2·β·T targetA comprehensive test was conducted at 40℃ to verify the cooling efficiency. If the cooling efficiency did not meet the standard, the values ​​of k1 and k2 were fine-tuned and the test was repeated until the performance met the target. Finally, stable values ​​of k1 and k2 were determined.

[0160] It is worth noting that the excitation voltage of the quantum dot coating is pulse width modulation, with a duty cycle adjustment accuracy of ±0.5%.

[0161] Specifically, the driving current of the TEC is determined based on the excitation voltage of the quantum dot coating and the internal resistance of the TEC.

[0162] Preferably, the drive current of the TEC is determined by the following formula:

[0163]

[0164] Among them, I TEC R represents the drive current of the TEC. TEC This indicates the internal resistance of the TEC.

[0165] It is worth noting that the driving current of the TEC acts as the primary agent to control the cold junction temperature, while the excitation voltage of the quantum dot coating acts as a secondary agent to control the cold junction temperature. The combination of the two improves the temperature control effect of the TEC's cold junction, resulting in better cooling performance of the cooled observation instrument in high-temperature environments and improving the measurement accuracy of the cooled observation instrument in high-temperature environments.

[0166] Specifically, such as Figure 3 As shown, in step S32, preferably, when the hot end temperature comparison result is that the real-time hot end temperature is greater than the first threshold temperature and less than or equal to the second threshold temperature, the hot end of the TEC is cooled by reducing the driving current of the TEC.

[0167] The drive current of the TEC is updated using the following formula:

[0168] I TEC =I′ TEC -k3·(T hot -T1);

[0169] Among them, I′ TEC I represents the drive current of the TEC before the update. TEC This represents the updated TEC drive current, k3 represents the current regulation coefficient, and T... hot T1 represents the real-time hot end temperature of the TEC, and T1 represents the first threshold temperature.

[0170] Specifically, when the real-time temperature of the hot end of the TEC is greater than the first threshold temperature and less than or equal to the second threshold temperature, the driving current I of the TEC is... TEC It cannot be increased any further, so I must begin to decrease. TECReduce I in a linear manner TEC For example, setting k3 to 0.1A / ℃ makes I TEC The linear decrease occurs when the hot end temperature is 65°C and the first threshold temperature is set to 60°C. The TEC drive current decreases from 5A before the update to 4.5A after the update.

[0171] Preferably, the cooling fan is started while the drive current of the TEC is updated, thereby increasing the speed of the cooling fan.

[0172] Preferably, when the hot end temperature comparison result shows that the real-time hot end temperature is greater than the second threshold temperature, the power supply to the TEC is cut off and an alarm is triggered.

[0173] Specifically, when the real-time temperature of the hot end of the TEC exceeds the second threshold temperature, the hot end temperature reaches its peak and cannot continue to work. At this time, the power supply to the TEC is cut off through the hardware fuse mechanism, triggering the buzzer to sound an alarm.

[0174] Preferably, the temperature control method further includes:

[0175] Determine whether the excitation voltage of the quantum dot coating is greater than a preset excitation voltage threshold; if not, do not apply an excitation voltage to the quantum dot coating; if yes, perform the following steps:

[0176] An excitation voltage is applied to the quantum dot coating, while simultaneously determining whether the driving current of the TEC is less than or equal to a preset driving current threshold. If not, no driving current is applied to the TEC; if yes, a driving current is applied to the TEC.

[0177] Specifically, the pre-set excitation voltage threshold needs to be set reasonably according to the material of the quantum dot coating to ensure that the quantum dot coating works normally when an excitation voltage is applied to it, so as to cool down the cold end.

[0178] Specifically, the preset drive current threshold is used to protect the circuit and prevent it from being damaged.

[0179] Unlike existing technologies where TEC relies solely on electrothermal conversion, this invention utilizes the synergistic effect of photothermal conversion via quantum dot coating and electrothermal conversion via TEC. Cadmium telluride quantum dots (CdTe) have a strong absorption peak near 980nm, which can convert ambient light into localized heat energy. This heat energy is then directed away through the cold end of the TEC, achieving a "light-heat-electric" energy transfer and constructing a three-domain (light-heat-electric) coupled refrigeration system. This overcomes the bottleneck of refrigeration efficiency degradation under high-temperature conditions.

[0180] Compared with existing technologies, the present invention provides a hybrid-mode-based temperature control method for an observation instrument, which flexibly adjusts the operating mode of the cooled observation instrument according to the external ambient temperature. Simultaneously, it determines the driving current of the TEC and / or the excitation voltage of the quantum dot coating in both high-temperature and low-temperature modes to control the TEC temperature, thereby improving the cooling effect of the observation instrument in complex temperature environments. Furthermore, by utilizing the internal light source wavelength, the external ambient light wavelength, the real-time cold end temperature of the TEC, and the target cold end cooling temperature in high-temperature mode to determine the driving current of the TEC and the excitation voltage of the quantum dot coating in real time, real-time control of the cold end temperature of the TEC is achieved, ensuring the cooling effect of the cooled observation instrument.

[0181] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A hybrid-mode based method for temperature control of an observer, the method comprising: The observation instrument temperature control method comprises: Obtaining the external environment temperature of the refrigeration observation instrument, and determining the working mode of the refrigeration observation instrument according to the external environment temperature; the working mode comprises a low-temperature mode and a high-temperature mode; According to the working mode of the refrigeration observation instrument, the driving current of the TEC and / or the excitation voltage of the quantum dot coating are determined to control the temperature of the TEC.

2. The method of claim 1, wherein The working mode of the refrigeration observation instrument is determined according to the external environment temperature, comprising: Judging whether the external environment temperature is greater than the mode switching temperature threshold value; If the external environment temperature is greater than the mode switching temperature threshold value, the working mode of the refrigeration observation instrument is switched to the high-temperature mode; Otherwise, the working mode of the refrigeration observation instrument is switched to the low-temperature mode.

3. The method of claim 1 or 2, wherein When the working mode of the refrigeration observation instrument is the low-temperature mode, the temperature of the TEC is controlled by the following steps: Obtaining the real-time temperature of the cold end of the TEC, and determining the cold end temperature real-time difference in combination with the cold end target refrigeration temperature; Judging whether the cold end temperature real-time difference is greater than the temperature difference threshold value; If the cold end temperature real-time difference is greater than the temperature difference threshold value, the working mode of the refrigeration observation instrument is switched from the low-temperature mode to the high-temperature mode; otherwise, the driving current of the TEC is realized to control the temperature of the TEC.

4. The method of claim 1 or 2, wherein When the working mode of the refrigeration observation instrument is the high-temperature mode, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined to control the temperature of the TEC by the following steps: Obtaining the internal light source wavelength and the external environment light wavelength of the refrigeration observation instrument, and obtaining the real-time temperature of the cold end and the real-time temperature of the hot end of the TEC; wherein the cold end surface of the TEC is coated with a quantum dot coating; Comparing the real-time temperature of the hot end with the first threshold temperature and the second threshold temperature to obtain the hot end temperature comparison result; According to the hot end temperature comparison result, in combination with the internal light source wavelength, the external environment light wavelength, the real-time temperature of the cold end of the TEC and the cold end target refrigeration temperature, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined to control the temperature of the TEC.

5. The method of claim 4, wherein the temperature of the scope is controlled by adjusting the temperature of the scope housing. The hot end temperature comparison result comprises: The real-time temperature of the hot end is less than or equal to the first threshold temperature; The real-time temperature of the hot end is greater than the first threshold temperature and less than or equal to the second threshold temperature; The real-time temperature of the hot end is greater than the second threshold temperature.

6. The method of claim 5, wherein the temperature of the scope is controlled by adjusting the temperature of the scope housing. When the hot end temperature comparison result is that the real-time temperature of the hot end is less than or equal to the first threshold temperature, the driving current of the TEC and the excitation voltage of the quantum dot coating are determined by the following steps: Judging whether the internal light source wavelength is within the inherent excitation wavelength range of the quantum dot coating; When the internal light source wavelength is within the inherent excitation wavelength range of the quantum dot coating, the following steps are performed: According to the external environment light wavelength and the inherent excitation wavelength of the quantum dot coating, the wavelength matching degree is determined, and according to the real-time temperature of the cold end of the TEC and the cold end target refrigeration temperature, the temperature difference weight is determined; According to the wavelength matching degree and the temperature difference weight, the excitation voltage of the quantum dot coating is determined; According to the excitation voltage of the quantum dot coating and the internal resistance of the TEC, the driving current of the TEC is determined.

7. The method of claim 6, wherein the temperature of the scope is controlled by adjusting the temperature of the scope housing. The wavelength matching degree is determined by the following formula: wherein a represents the wavelength matching degree, λ env represents the wavelength of the external ambient light, λ qd represents the inherent excitation wavelength of the quantum dot coating; The temperature difference weight is determined by the following formula: wherein β represents a temperature difference weight, T cold represents a real-time temperature of the cold end of the TEC, T target represents a target refrigeration temperature of the cold end.

8. The method of claim 7, wherein the temperature of the scope is controlled by adjusting the temperature of the air supplied to the scope. The excitation voltage of the quantum dot coating is determined by the following formula: V qd = k1 · a + k2 · b · T target ; V = k1 * V1 + k2 * V2 qd Vexc represents the excitation voltage of the quantum dot coating, k1 and k2 represent the first calibration coefficient and the second calibration coefficient, respectively. The driving current of the TEC is determined by the following formula: where I TEC represents the driving current of the TEC, R TEC represents the internal resistance of the TEC.

9. The method of claim 5, wherein the temperature of the scope is controlled by a temperature control system. when the hot end temperature comparison result is that the real-time hot end temperature is greater than the first threshold temperature and less than or equal to the second threshold temperature, cooling the hot end of the TEC by reducing the drive current of the TEC; the drive current of the TEC is updated by the following formula: I TEC = I' TEC - k3- (T hot - T1); Among them, I′ TEC I represents the drive current of the TEC before the update. TEC This represents the updated TEC drive current, k3 represents the current regulation coefficient, and T... hot T1 represents the real-time hot end temperature of the TEC, and T1 represents the first threshold temperature.

10. The method of claim 5, wherein the temperature of the scope is controlled by a temperature control system. when the hot end temperature comparison result is that the real-time hot end temperature is greater than the second threshold temperature, cutting off the power supply of the TEC, and simultaneously performing an alarm.

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