Binary-based infrared action distance calculation method and system

Abstract

The application discloses an infrared action distance calculation method based on dichotomy, which comprises the following steps: S1, acquiring atmospheric environment information and infrared detector information, and calculating atmospheric transmissivity under different observation distances; S2, fitting the observation distance and the atmospheric transmissivity, bringing the fitting equation into an infrared action distance calculation equation and simplifying to obtain a simplified equation; and S3, according to the limit maximum value and the limit minimum value of the infrared action distance, the dichotomy is used to iteratively optimize and calculate the final infrared action distance R. The application can reduce the process of repeated artificial iterative calculation, guarantee the accuracy, and greatly shorten the calculation time.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic equipment, and in particular to a method and system for calculating infrared operating distance based on the dichotomy method. Background Technology

[0002] The effective range of an infrared detection system is a comprehensive indicator for evaluating infrared imaging equipment. It is related to various factors, including overall atmospheric transmittance, detector performance parameters, target characteristics, and environmental parameters. Currently, a common method is to use software such as PcModwin to calculate atmospheric transmittance and then substitute it into the infrared effective range calculation equation given by RD Hudson Jr. PcModwin is a commercial Windows version of the international standard atmospheric model MODTRAN, which is a standard model developed by the U.S. Air Force Geophysical Laboratory for calculating atmospheric transmittance and radiation. PcModwin covers the ultraviolet-visible-infrared-microwave range (0–50,000 cm⁻¹). -1 This atmospheric transmission simulation software system integrates the latest atmospheric science research findings and possesses the most comprehensive functional characteristics and the highest technical specifications (spectral resolution up to 0.1 cm⁻¹). -1 This approach enables convenient use and a user-friendly interface for the MODTRAN model. However, atmospheric transmittance is related to observation distance, requiring an iterative process that demands significant manpower and time, and currently, there is no satisfactory solution. Summary of the Invention

[0003] The main objective of this invention is to provide an infrared range calculation method and system based on the bisection method, which has a fast calculation speed and can reduce the process of repeated manual iterative calculations.

[0004] The technical solution adopted in this invention is:

[0005] A method for calculating infrared range based on the bisection method is provided, comprising the following steps:

[0006] S1. Acquire atmospheric environmental information and infrared detector information, and calculate atmospheric transmittance at different observation distances;

[0007] S2. Fit the observation distance and atmospheric transmittance, substitute the fitting equation (2) into the infrared range calculation equation (1) to obtain equation (3), and simplify to obtain simplified equation (4):

[0008]

[0009] τ=αexp(βR)(2)

[0010]

[0011] R 2 = Aexp(BR) (4)

[0012] Where R is the final infrared action distance; D0 is the objective lens aperture; NA is the numerical aperture, D* is the infrared sensor detection sensitivity; ΔJ is the infrared radiation amount; K is the optical transmittance; τ is the atmospheric transmittance; ω is the instantaneous solid angle of view of the infrared sensor; Δf is the electronic bandwidth; V s / V n is the SNR signal-to-noise ratio; ξ is the coefficient caused by the signal processing loss factor; α, β are the fitting parameters of the observation distance and the atmospheric transmittance;

[0013] B = β;

[0014] S3. According to the maximum and minimum limits of the infrared action distance, use the bisection method to iteratively optimize and calculate the final infrared action distance R.

[0015] Continuing with the above technical solution, step S3 specifically includes:

[0016] S31: Assign values to the minimum value Rmin and the maximum value Rmax of the infrared action distance;

[0017] S32: Assign a value to the intermediate distance r, r = (Rmax + Rmin) / 2, and calculate r 2 and Aexp(Br);

[0018] S33: If r 2 > Aexp(Br), then set the maximum value Rmax to the current intermediate distance r value. If r 2 < Aexp(Br), then set the minimum value Rmin to the current intermediate distance r value;

[0019] S34: Calculate the difference (Rmax - Rmin). If (Rmax - Rmin) < 1 km, then the infrared action distance R = (Rmax + Rmin) / 2, and exit the calculation. Otherwise, repeat steps S32 and S33.

[0020] Continuing with the above technical solution, in step S1, the atmospheric transmittance at different observation distances is calculated by PcModwin software.

[0021] Continuing with the above technical solution, NA = 1 / 2F, where F is the large F number of the optical system.

[0022] Continuing with the above technical solution, the value of the infrared detection sensitivity D* is 2 - 3×10 11 cmHz 0.5 / W.

[0023] Following the above technical solution, the optical transmittance K is set to 0.6 to 0.8.

[0024] Following the above technical solution, the minimum value Rmin is 1km and the maximum value Rmax is 200km.

[0025] Following the above technical solution, the instantaneous stereo field of view angle ω of the infrared sensor is ω=a*b / f 2 , where a and b are pixel sizes, and f is the focal length.

[0026] Following the above technical solution, Δf is the electronic bandwidth, Δf = 1 / 2Tint, and Tint is the infrared integration time.

[0027] This invention also provides an infrared range calculation system based on the bisection method, comprising:

[0028] The atmospheric transmittance calculation module is used to acquire atmospheric environmental information and infrared detector information, and to calculate atmospheric transmittance at different observation distances.

[0029] The fitting module is used to fit the observation distance and atmospheric transmittance. Substituting the fitting equation (2) into the infrared range calculation equation (1) yields equation (3), which is then simplified to equation (4):

[0030]

[0031] τ=αexp(βR)(2)

[0032]

[0033] R 2 =Aexp(BR)(4)

[0034] Where R is the final infrared range; D0 is the objective lens aperture; NA is the numerical aperture; D* is the infrared sensor detection sensitivity; ΔJ is the infrared radiation; K is the optical transmittance; τ is the atmospheric transmittance; ω is the instantaneous stereo field of view of the infrared sensor; Δf is the electronic bandwidth; V s / V n ξ is the signal-to-noise ratio (SNR); ξ is the coefficient caused by signal processing loss factors; α and β are the fitting parameters between observation distance and atmospheric transmittance.

[0035] B = β;

[0036] The bisection iterative module is used to calculate the infrared range R by using the bisection iterative optimization based on the maximum and minimum limits of the infrared range.

[0037] The beneficial effects of this invention are as follows: This patent calculates the observation distance and atmospheric transmittance under a certain environment, uses a fitting method to fit the fitting equation between the observation distance and atmospheric transmittance, and then uses a bisection method for rapid iterative optimization to calculate the final infrared range. This invention can reduce the process of repeated manual iterative calculations, greatly shortening the calculation time while ensuring accuracy. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a flowchart of the infrared range calculation method based on the bisection method according to an embodiment of the present invention;

[0040] Figure 2 This is a curve showing the fitting relationship between observation distance and atmospheric transmittance in an embodiment of the present invention;

[0041] Figure 3 This is a flowchart illustrating the specific process of the binary iterative optimization algorithm according to an embodiment of the present invention. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0043] The overall inventive concept of this invention is as follows: Based on atmospheric environmental information and infrared detector information, atmospheric transmittance is calculated at different observation distances; the observation distance and atmospheric transmittance are fitted to derive a fitting equation between the infrared effective range and atmospheric transmittance; this fitted equation is substituted into the infrared effective range calculation equation given by R.D. Hudson Jr. to obtain the calculation equation, and then the infrared effective range value is obtained by iteratively applying a bisection method. This invention can reduce the process of repeated manual iterative calculations, greatly shortening the calculation time while ensuring accuracy, and achieving automatic calculation from minutes to milliseconds.

[0044] like Figure 1 As shown, the infrared range calculation method based on the bisection method in this embodiment of the invention includes the following steps:

[0045] S1. Acquire atmospheric environmental information and infrared detector information, and calculate atmospheric transmittance at different observation distances;

[0046] S2. Fit the observation distance and atmospheric transmittance, substitute the fitting equation (2) into the infrared range calculation equation (1) to obtain equation (3), and simplify to obtain simplified equation (4):

[0047]

[0048] τ=αexp(βR)(2)

[0049]

[0050] R 2 =Aexp(BR)(4)

[0051] Where R is the final infrared range; D0 is the objective lens aperture; NA is the numerical aperture; D* is the infrared sensor detection sensitivity; ΔJ is the infrared radiation; K is the optical transmittance; τ is the atmospheric transmittance; ω is the instantaneous stereo field of view of the infrared sensor; Δf is the electronic bandwidth; V s / V n ξ is the signal-to-noise ratio (SNR); ξ is the coefficient caused by signal processing loss factors; α and β are the fitting parameters between observation distance and atmospheric transmittance.

[0052] B = β;

[0053] S3. Based on the maximum and minimum limits of the infrared range, the final infrared range R is calculated using the bisection method iterative optimization.

[0054] Specifically, D0 is the objective lens diameter, i.e., the lens aperture; NA is the numerical aperture, NA = 1 / 2F, where the F-number is the reciprocal of the lens's relative aperture, which is equal to the entrance pupil diameter divided by the focal length, i.e., the F-number equals the focal length divided by the entrance pupil diameter; D* is the detection sensitivity, typically 2–3 × 10⁻⁶. 11 cmHz 0.5 / W, commonly 3; ΔJ is the difference in infrared radiation intensity between the target and the background, i.e., the amount of infrared radiation; K is the optical transmittance, generally 0.6 to 0.8; τ is the atmospheric transmittance, calculated using PcModWin; ω is the instantaneous stereo field of view angle, ω = a*b / f^2, where a and b are the pixel size and f is the lens focal length; Δf is the electronic bandwidth, Δf = 1 / 2Tint, where Tint is the infrared integration time; Vs / Vn is the signal-to-noise ratio, i.e., SNR, generally above 10; ξ is a coefficient caused by factors such as signal processing loss, ranging from 0 to 1, which can be obtained based on empirical values.

[0055] In step S1, atmospheric transmittance can be obtained either by instrument measurement or by setting atmospheric environment information and infrared detector information in PcModwin software, and then calculated at different observation distances, as shown in Table 1 below:

[0056] Table 1. Correspondence between observation distance and atmospheric transmittance under certain conditions.

[0057] Observation distance (km) Atmospheric transmittance 10 0.1092 11 0.0933 12 0.0798 13 0.0684 14 0.0586 15 0.0504 16 0.0433 17 0.0373 18 0.0321 19 0.0277 20 0.0239 21 0.0207 22 0.0179 23 0.0155 24 0.0134 25 0.0116 26 0.0101 27 0.009 28 0.0076 29 0.0066 30 0.0057 31 0.0049 32 0.0043 33 0.0037 34 0.0033 35 0.0028 36 0.0025

[0058] By fitting the model, the relationship between observation distance and atmospheric transmittance is determined, as shown in the attached figure. Figure 2 As shown.

[0059] like Figure 3 As shown, the infrared range R can be obtained by using the following algorithm flow (4).

[0060] S31: Take Rmin as 1km and Rmax as 200km;

[0061] S32: Calculate (Rmax-Rmin) and determine if (Rmax-Rmin) < 1km. If yes, proceed to step S33; otherwise, proceed to step S34.

[0062] S33: If (Rmax-Rmin) < 1km, then let the infrared range R = (Rmax+Rmin) / 2, and exit the calculation;

[0063] S34: If (Rmax-Rmin)≥1km, then take r=(Rmax+Rmin) / 2, and calculate r respectively. 2 With Aexp(Br);

[0064] S35: Determine r 2 If Aexp(Br) is true, proceed to step S36; otherwise, proceed to step S37.

[0065] S36: If r 2 If Aexp(Br), then let Rmax = r, and proceed to step S32;

[0066] S37: If r 2 If ≤Aexp(Br), then let Rmin=r and proceed to step S32.

[0067] The infrared range calculation system based on the bisection method in this invention is mainly used to implement the above-mentioned method embodiments. The system includes:

[0068] The atmospheric transmittance calculation module is used to acquire atmospheric environmental information and infrared detector information, and to calculate atmospheric transmittance at different observation distances.

[0069] The fitting module is used to fit the observation distance and atmospheric transmittance. Substituting the fitting equation (2) into the infrared range calculation equation (1) yields equation (3), which is then simplified to equation (4):

[0070]

[0071] τ=αexp(βR)(2)

[0072]

[0073] R 2 =Aexp(BR)(4)

[0074] Where R is the final infrared range; D0 is the objective lens aperture; NA is the numerical aperture; D* is the infrared sensor detection sensitivity; ΔJ is the infrared radiation; K is the optical transmittance; τ is the atmospheric transmittance; ω is the instantaneous stereo field of view of the infrared sensor; Δf is the electronic bandwidth; V s / V n ξ is the signal-to-noise ratio (SNR); ξ is the coefficient caused by signal processing loss factors; α and β are the fitting parameters between observation distance and atmospheric transmittance.

[0075] B = β;

[0076] The bisection iterative module is used to calculate the infrared range R by using the bisection iterative optimization based on the maximum and minimum limits of the infrared range.

[0077] In the preferred embodiment of the system, each module is specifically used to implement the above preferred method embodiment, which will not be elaborated here.

[0078] This application also provides a non-transitory computer-readable storage medium, such as flash memory, hard disk, multimedia card, card-type memory (e.g., SD or DX memory), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, disk, optical disk, server, app store, etc., which stores a computer program. When the program is executed by a processor, it implements the corresponding function. The computer-readable storage medium of this embodiment is used to implement the infrared range calculation method based on the binary search method of the method embodiment when executed by a processor.

[0079] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A method for calculating infrared range based on the bisection method, characterized in that, Includes the following steps: S1. Acquire atmospheric environmental information and infrared detector information, and calculate atmospheric transmittance at different observation distances; S2. Fit the observation distance and atmospheric transmittance, substitute the fitting equation (2) into the infrared range calculation equation (1) to obtain equation (3), and simplify to obtain simplified equation (4): （1） （2） （3） （4） in, R This represents the final infrared effective range; D 0 represents the objective lens diameter; NA Numerical aperture, For the infrared sensor detection sensitivity; Δ J Infrared radiation; K τ is the optical transmittance; ω is the atmospheric transmittance; ω is the instantaneous stereo field of view of the infrared sensor; Δ f For electronic bandwidth; V s / V n SNR is the signal-to-noise ratio; ξ is the coefficient caused by signal processing loss factors. The first fitting parameter for observation distance and atmospheric transmittance is... This is the second fitting parameter between the observation distance and atmospheric transmittance; , ; S3. Based on the maximum and minimum limits of the infrared range, the final infrared range R is calculated using the bisection method iterative optimization. Specifically, step S3 includes: S31: Assign values ​​to the minimum and maximum infrared range Rmin and Rmax. S32: Assign a value to the intermediate distance r, r = (Rmax + Rmin) / 2, and calculate the values ​​respectively. and ; S33: If > Then let the maximum value Rmax be the value of the current intermediate distance r. < Let the minimum value Rmin be the value of the current intermediate distance r; S34: Calculate the difference (Rmax-Rmin). If (Rmax-Rmin) < 1km, then the infrared range R = (Rmax+Rmin) / 2. Exit the calculation. Otherwise, repeat steps S32 and S33.

2. The infrared range calculation method based on the bisection method according to claim 1, characterized in that, In step S1, atmospheric transmittance at different observation distances is calculated using PcModwin software.

3. The infrared range calculation method based on the bisection method according to claim 1, characterized in that, NA =1 / 2F, where F is the F-number of the optical system.

4. The infrared range calculation method based on the bisection method according to claim 1, characterized in that, Infrared sensor detection sensitivity The value ranges from 2 to 3 × 10. 11 cmHz 0.5 / W.

5. The infrared range calculation method based on the bisection method according to claim 1, characterized in that, Optical transmittance K The value ranges from 0.6 to 0.

8.

6. The infrared range calculation method based on the bisection method according to claim 1, characterized in that, In step S31, the minimum value Rmin is 1km and the maximum value Rmax is 200km.

7. The infrared range calculation method based on the bisection method according to claim 1, characterized in that, Instantaneous stereo field of view of infrared sensor ,in , For pixel size, It is the focal length.

8. The infrared range calculation method based on the bisection method according to claim 1, characterized in that, Δ f For the electron bandwidth, Δ f= 1 / 2Tint, where Tint is the infrared integration time.

9. An infrared range calculation system based on the bisection method, characterized in that, include: The atmospheric transmittance calculation module is used to acquire atmospheric environmental information and infrared detector information, and to calculate atmospheric transmittance at different observation distances. The fitting module is used to fit the observation distance and atmospheric transmittance. Substituting the fitting equation (2) into the infrared range calculation equation (1) yields equation (3), which is then simplified to equation (4): （1） （2） （3） （4） in, R This represents the final infrared effective range; D 0 represents the objective lens diameter; NA Numerical aperture, For the infrared sensor detection sensitivity; Δ J Infrared radiation; K τ is the optical transmittance; ω is the atmospheric transmittance; ω is the instantaneous stereo field of view of the infrared sensor; Δ f For electronic bandwidth; V s / V n SNR is the signal-to-noise ratio; ξ is the coefficient caused by signal processing loss factors. The first fitting parameter for observation distance and atmospheric transmittance is... This is the second fitting parameter between the observation distance and atmospheric transmittance; , ; The bisection iteration module is used to calculate the infrared range R by using the bisection method iterative optimization based on the maximum and minimum limits of the infrared range. Specifically, the bisection iteration module performs the following steps: S31: Assign values ​​to the minimum and maximum infrared range Rmin and Rmax. S32: Assign a value to the intermediate distance r, r = (Rmax + Rmin) / 2, and calculate the values ​​respectively. and ; S33: If > Then let the maximum value Rmax be the value of the current intermediate distance r. < Let the minimum value Rmin be the value of the current intermediate distance r; S34: Calculate the difference (Rmax-Rmin). If (Rmax-Rmin) < 1km, then the infrared range R = (Rmax+Rmin) / 2. Exit the calculation. Otherwise, repeat steps S32 and S33.

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