Infrared thermal imager lens compensation method

Abstract

This application belongs to the field of infrared thermal imager technology, and particularly relates to a lens compensation method for infrared thermal imagers. The method includes: mounting a standard lens on a standard prototype (defined as a standard device), bringing the standard device to thermal equilibrium, and then collecting data on a blackbody at different temperatures to obtain a reference grayscale array for a normal temperature environment; setting multiple ambient temperatures, maintaining the test device at one of these temperatures for two hours until thermal equilibrium is reached, and then collecting data on a blackbody at different temperatures until data collection is completed at all ambient temperatures to obtain a total test grayscale array; constructing a temperature compensation fitting model based on the reference grayscale array and the total test grayscale array; and applying the temperature compensation fitting model to the infrared thermal imager. This compensation method improves compensation accuracy by collecting grayscale values ​​at multiple ambient temperatures and then constructing a temperature compensation fitting model.

Description

Technical Field

[0001] This application relates to the field of infrared thermal imager technology, and in particular to an infrared thermal imager lens compensation method. Background Technology

[0002] Currently, infrared thermal imagers all have interchangeable lenses. However, when users need to replace the lens, the infrared thermal imager needs to be recalibrated for temperature, which is time-consuming, labor-intensive, and affects the user experience.

[0003] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art.

[0004] Application content

[0005] In view of at least one of the above technical problems, this application provides a method for compensating the lens of an infrared thermal imager.

[0006] This application provides a method for compensating the lens of an infrared thermal imager, the method comprising:

[0007] S100. Install the standard lens on the standard prototype. At this time, the equipment is defined as a standard equipment. Make the standard equipment reach thermal equilibrium. Then collect data on blackbodies at different temperatures to obtain a reference grayscale array for the normal temperature environment.

[0008] S200: Set multiple ambient temperatures, keep the test equipment at one of the multiple ambient temperatures for two hours until it reaches thermal equilibrium, and then collect data on the blackbody at different temperatures until the data collection is completed at all ambient temperatures to obtain the total grayscale array of the test.

[0009] S300. Based on the reference grayscale array of the normal temperature environment and the total grayscale array of the test, a temperature compensation fitting model is constructed.

[0010] S400: Apply the temperature compensation fitting model to the infrared thermal imager.

[0011] This compensation method collects grayscale values ​​of multiple ambient temperatures and then constructs a temperature compensation fitting model, which can accurately capture the differentiated response of the lens at different stages such as low-temperature contraction and high-temperature expansion, thereby improving the compensation accuracy.

[0012] In some possible implementations, the ambient temperature is 25°C.

[0013] In some possible implementations, the temperature of the blackbody includes -10°C, 0°C, 20°C, 50°C, 80°C, 120°C, and 150°C.

[0014] In some possible implementations, obtaining the ambient temperature environment reference grayscale array includes:

[0015] S110. Under normal temperature conditions, perform 10 grayscale value acquisitions on a blackbody at any temperature, and take the average of the 10 grayscale values ​​to generate a reference grayscale value at the corresponding blackbody temperature.

[0016] S120. Repeat step S110 to collect the remaining blackbody temperature and obtain multiple reference grayscale values.

[0017] S130. Based on multiple reference grayscale values, obtain a reference grayscale array for normal temperature environment.

[0018] In some possible implementations, the ambient temperature includes 0°C, 15°C, 25°C, 35°C, and 50°C.

[0019] In some possible implementations, obtaining the test grayscale array includes:

[0020] S210. At any ambient temperature, collect grayscale values ​​of a blackbody at any temperature 10 times, and take the average of the grayscale values ​​obtained from the 10 collections to generate the test grayscale value at the corresponding blackbody temperature.

[0021] S220. Repeat step S210 to collect the remaining blackbody temperature and obtain multiple test grayscale values.

[0022] S230. Based on multiple test grayscale values, obtain the test grayscale array at the corresponding ambient temperature;

[0023] S240. Repeat steps S210 to S230 to collect the remaining ambient temperatures and obtain multiple test grayscale arrays under different ambient temperatures.

[0024] S250. Based on multiple test grayscale arrays, obtain the total test grayscale array.

[0025] In some possible implementations, the calculation formula for the temperature compensation fitting model is as follows:

[0026] LensGrays=P0+P1*Ambient+P2*FreeGray+P3*Ambient 2 +

[0027] P4*FreeGray 2 +P5*FreeGray 3 +P6*Ambient*FreeGray+

[0028] P7*Ambient 2*FreeGray+P8*FreeGray 2 Ambient

[0029] Where LensGrays represents the compensated grayscale values, P0 to P8 are the compensation coefficients, Ambient represents the ambient temperature, and FreeGray represents the values ​​in the test grayscale array corresponding to the ambient temperature.

[0030] The present application will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a flowchart illustrating the infrared thermal imager lens compensation method in the embodiments of this application; Detailed Implementation

[0033] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0034] like Figure 1 As shown, one embodiment provides an infrared thermal imager lens compensation method, the method comprising: S100 to S400.

[0035] S100. Install the standard lens on the standard prototype. At this time, the device is defined as a standard device. Make the standard device reach thermal equilibrium. Then, collect data on blackbodies at different temperatures to obtain a reference grayscale array for the normal temperature environment.

[0036] It is worth noting that the ambient temperature is 25°C, and the temperature of the blackbody includes -10°C, 0°C, 20°C, 50°C, 80°C, 120°C, and 150°C.

[0037] It is understandable that the standard lens and standard prototype serve as ideal devices in lens compensation, meaning that subsequent lenses to be compensated will infinitely approach the standard lens. Therefore, the reference grayscale array for a normal temperature environment serves as the ideal compensation output value.

[0038] Specifically, obtaining the ambient temperature environment reference grayscale array includes:

[0039] S110. Under normal temperature conditions, perform 10 grayscale value acquisitions on a blackbody at any temperature, and take the average of the 10 grayscale values ​​to generate a reference grayscale value at the corresponding blackbody temperature.

[0040] S120. Repeat step S110 to collect the remaining blackbody temperature and obtain multiple reference grayscale values.

[0041] S130. Based on multiple reference grayscale values, obtain a reference grayscale array for normal temperature environment.

[0042] For example, at 25℃, grayscale values ​​are collected 10 times for a blackbody at -10℃, and the average of these 10 grayscale values ​​is taken to generate a reference grayscale value for a blackbody temperature of -10℃. At 25℃, grayscale values ​​are collected 10 times for a blackbody at 0℃, and the average of these 10 grayscale values ​​is taken to generate a reference grayscale value for a blackbody temperature of 0℃. Following the above operation, grayscale values ​​are collected for blackbody temperatures of 20℃, 50℃, 80℃, 120℃, and 150℃, finally generating a reference grayscale array for normal temperature environments, as shown in Table 1 below.

[0043]

[0044] Table 1 shows the reference grayscale array for normal temperature environments.

[0045] S200: Set multiple ambient temperatures, keep the test equipment at one of the multiple ambient temperatures for two hours until it reaches thermal equilibrium, and then collect data on the blackbody at different temperatures until the data collection is completed at all ambient temperatures to obtain the total grayscale array.

[0046] It is worth noting that the ambient temperature includes 0℃, 15℃, 25℃, 35℃ and 50℃.

[0047] Specifically, obtaining the test grayscale array includes:

[0048] S210. At any ambient temperature, collect grayscale values ​​of a blackbody at any temperature 10 times, and take the average of the grayscale values ​​obtained from the 10 collections to generate the test grayscale value at the corresponding blackbody temperature.

[0049] S220. Repeat step S210 to collect the remaining blackbody temperature and obtain multiple test grayscale values.

[0050] S230. Based on multiple test grayscale values, obtain the test grayscale array at the corresponding ambient temperature;

[0051] S240. Repeat steps S210 to S230 to collect the remaining ambient temperatures and obtain multiple test grayscale arrays under different ambient temperatures.

[0052] S250. Based on multiple test grayscale arrays, obtain the total test grayscale array.

[0053] For example, at 0℃, grayscale values ​​are collected 10 times for a blackbody at -10℃, and the average of these 10 grayscale values ​​is taken to generate a test grayscale value for a blackbody temperature of -10℃. Following the same procedure, grayscale values ​​are collected at blackbody temperatures of 0℃, 20℃, 50℃, 80℃, 120℃, and 150℃ to obtain a test grayscale array for an ambient temperature of 0℃.

[0054] At 15℃, grayscale values ​​were collected 10 times for a blackbody at -10℃, and the average of these 10 grayscale values ​​was taken to generate a test grayscale value for a blackbody temperature of -10℃. Following the same procedure, grayscale values ​​were collected at blackbody temperatures of 0℃, 20℃, 50℃, 80℃, 120℃, and 150℃ to obtain a test grayscale array for an ambient temperature of 15℃.

[0055] Following the above steps, data were collected at ambient temperatures of 25℃, 35℃, and 50℃, and the final test grayscale array was generated, as shown in Table 2 below.

[0056]

[0057] Table 2 shows the total grayscale array for testing.

[0058] S300. Based on the reference grayscale array of the normal temperature environment and the total grayscale array of the test, a temperature compensation fitting model is constructed.

[0059] The calculation formula for the temperature compensation fitting model is as follows:

[0060] LensGrays=P0+P1*Ambient+P2*FreeGray+P3*Ambient 2 +

[0061] P4*FreeGray 2 +P5*FreeGray 3 +P6*Ambient*FreeGray+

[0062] P7*Ambient 2 *FreeGray+P8*FreeGray 2 Ambient

[0063] Where LensGrays represents the compensated grayscale values, P0 to P8 are the compensation coefficients, Ambient represents the ambient temperature, and FreeGray represents the values ​​in the test grayscale array corresponding to the ambient temperature.

[0064] It is worth noting that when constructing the temperature compensation fitting model, the compensation coefficients P0 to P8 need to be calculated. In this model, LensGrays is substituted with the values ​​in the reference grayscale array of the normal temperature environment, Ambient is substituted with the ambient temperature in the total grayscale array of the test, and FreeGray is substituted with the grayscale values ​​under the same blackbody temperature and ambient temperature.

[0065] For example, taking a blackbody temperature of -10℃ and an ambient temperature of 0℃ as an example, the calculation equation of the temperature compensation fitting model is:

[0066] 1265=P0+P1*0+P2*1705+P3*0 2 +

[0067] P4*1705 2 +P5*1705 3 +P6*0*1705+

[0068] P7*0 2 *1705+P8*1705 2 *0

[0069] For example, taking a blackbody temperature of -10℃ and an ambient temperature of 15℃ as an example, the calculation equation of the temperature compensation fitting model is:

[0070] 1265 = P0 + P1*15 + P2*1585 + P3*15 2 +

[0071] P4*1585 2 +P5*1585 3 +P6*15*1585+

[0072] P7*15 2 *1585+P8*1585 2 *15

[0073] Thus, multiple equations are constructed, and the compensation coefficients P0 to P8 are calculated, as shown in Table 3 below.

[0074]

[0075]

[0076] Table 3 shows the values ​​of the compensation coefficient.

[0077] S400: Apply the temperature compensation fitting model to the infrared thermal imager.

[0078] This compensation method collects grayscale values ​​of multiple ambient temperatures and then constructs a temperature compensation fitting model, which can accurately capture the differentiated response of the lens at different stages such as low-temperature contraction and high-temperature expansion, thereby improving the compensation accuracy.

[0079] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0080] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0081] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0082] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0083] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0084] Those skilled in the art will understand that all or part of the steps of the methods described in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it includes one or a combination of the steps of the method embodiments. The storage medium mentioned above can be a read-only memory, a magnetic disk, or an optical disk, etc.

[0085] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0086] The above description is merely a preferred embodiment of this application and does not constitute any limitation on this application. Any person skilled in the art can make many possible variations and modifications to the technical solution of this application, or modify it into equivalent embodiments, without departing from the scope of the technical solution of this application. Therefore, all equivalent changes made based on the shape, structure, and principle of this application without departing from the content of the technical solution of this application should be covered within the protection scope of this application.

Claims

1. A method for compensating the lens of an infrared thermal imager, characterized in that, The method includes: S100. Install the standard lens on the standard prototype. At this time, the equipment is defined as a standard equipment. Make the standard equipment reach thermal equilibrium. Then collect data on blackbodies at different temperatures to obtain a reference grayscale array for the normal temperature environment. S200: Set multiple ambient temperatures, keep the test equipment at one of the multiple ambient temperatures for two hours until it reaches thermal equilibrium, and then collect data on the blackbody at different temperatures until the data collection is completed at all ambient temperatures to obtain the total grayscale array of the test. S300. Based on the reference grayscale array of the normal temperature environment and the total grayscale array of the test, a temperature compensation fitting model is constructed. S400, Apply the temperature compensation fitting model to the infrared thermal imager; The calculation formula for the temperature compensation fitting model is as follows: ， Where LensGrays is the compensated grayscale value, P0 to P8 are the compensation coefficients, Ambient is the ambient temperature, and FreeGray is the value in the test grayscale array at the corresponding ambient temperature. When constructing the temperature compensation fitting model, the compensation coefficients P0 to P8 are calculated. Among them, LensGrays is substituted with the value in the reference grayscale array of the normal temperature environment, Ambient is substituted with the ambient temperature in the total grayscale array of the test, and FreeGray is substituted with the grayscale value under the same blackbody temperature and ambient temperature.

2. The infrared thermal imager lens compensation method according to claim 1, characterized in that, The ambient temperature is 25℃.

3. The infrared thermal imager lens compensation method according to claim 1, characterized in that, The temperatures of the blackbody include -10℃, 0℃, 20℃, 50℃, 80℃, 120℃, and 150℃.

4. The infrared thermal imager lens compensation method according to claim 1, characterized in that, The process of obtaining the ambient temperature environment reference grayscale array includes: S110. Under normal temperature conditions, perform 10 grayscale value acquisitions on a blackbody at any temperature, and take the average of the 10 grayscale values ​​to generate a reference grayscale value at the corresponding blackbody temperature. S120. Repeat step S110 to collect the remaining blackbody temperature and obtain multiple reference grayscale values. S130. Based on multiple reference grayscale values, obtain a reference grayscale array for normal temperature environment.

5. The infrared thermal imager lens compensation method according to claim 1, characterized in that, The ambient temperatures include 0℃, 15℃, 25℃, 35℃, and 50℃.

6. The infrared thermal imager lens compensation method according to claim 1, characterized in that, The obtained test grayscale array includes: S210. At any ambient temperature, collect grayscale values ​​of a blackbody at any temperature 10 times, and take the average of the grayscale values ​​obtained from the 10 collections to generate the test grayscale value at the corresponding blackbody temperature. S220. Repeat step S210 to collect the remaining blackbody temperature and obtain multiple test grayscale values. S230. Based on multiple test grayscale values, obtain the test grayscale array at the corresponding ambient temperature; S240. Repeat steps S210 to S230 to collect the remaining ambient temperatures and obtain multiple test grayscale arrays under different ambient temperatures. S250. Based on multiple test grayscale arrays, obtain the total test grayscale array.

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