CN113092069B - Method and device for measuring stray radiation in large-diameter infrared photoelectric system - Google Patents
Method and device for measuring stray radiation in large-diameter infrared photoelectric system Download PDFInfo
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- CN113092069B CN113092069B CN201911336604.2A CN201911336604A CN113092069B CN 113092069 B CN113092069 B CN 113092069B CN 201911336604 A CN201911336604 A CN 201911336604A CN 113092069 B CN113092069 B CN 113092069B
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- 230000036760 body temperature Effects 0.000 claims abstract description 7
- 230000005693 optoelectronics Effects 0.000 claims description 19
- 238000000691 measurement method Methods 0.000 claims description 3
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- G—PHYSICS
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- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
- G01M11/02—Testing optical properties
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
Abstract
The invention provides a method and a device for measuring stray radiation in a large-caliber infrared photoelectric system, comprising the following steps: after the positions of the infrared photoelectric system to be measured and the black body are adjusted to be aligned in parallel, the temperature of the black body is changed so as to carry out radiometric calibration on the infrared photoelectric system to be measured and obtain response gain G 0 And a response bias h det1 And h det2 (ii) a Obtaining the current ambient temperature T amb0 Raising the black body temperature to T 1 At integration time t 0 Next, an image h (t) is acquired 0 ,T 1 ,T amb0 ) (ii) a Continuing to raise the temperature of the black body to T 2 At integration time t (t ≠ t) 0 ) Next, an image h (T, T) is acquired 2 ,T amb0 ) (ii) a Calculating stray radiation response coefficient G according to formula stray And then the internal stray radiation of the infrared photoelectric system is measured at different temperatures, a low-temperature experiment box is not needed in the process, and the measurement and calculation process is simple and easy to realize.
Description
Technical Field
The invention relates to the technical field of photoelectric radiation measurement, in particular to a method and a device for measuring stray radiation in a large-caliber infrared photoelectric system.
Background
The ground-based infrared imaging system is an important component of the optical observation equipment of the target range, and along with the rapid development of the infrared technology, the measurement and control technology and the equipment technology, the ground-based infrared imaging system of the target range is also widely applied to the infrared radiation characteristic measurement of military targets of the target range. The radiation characteristic measurement is actually one of quantitative remote sensing technologies, the quantification means that the system needs to be calibrated, and the radiation calibration technology based on a standard reference radiation source is the basis of high-precision infrared radiation characteristic measurement. Since the infrared system is sensitive to heat energy, the change of the system output caused by the change of the environmental temperature in the process of radiometric calibration or radiometric characteristic measurement is represented as the drift of the system output gray scale along with the change of the environmental temperature, which limits the accuracy of radiometric characteristic measurement and the stability of the measurement result. Therefore, for some systems with high measurement accuracy requirements, the ambient temperature is generally required to be stable during the radiation calibration and the target radiation characteristic measurement, and the ambient conditions of the two are the same.
In view of the above, there is a need to provide a new measurement method.
Disclosure of Invention
The invention mainly aims to provide a method and a device for measuring stray radiation in a large-caliber infrared photoelectric system, and aims to solve the problem that the large-caliber infrared photoelectric system in the prior art cannot measure the stray radiation in a temperature control box.
In order to achieve the above object, the present invention provides a method for measuring stray radiation in a large-aperture infrared optoelectronic system, where the method includes:
after the positions of the infrared photoelectric system to be measured and the black body are adjusted to be aligned in parallel, the temperature of the black body is changed so as to carry out radiometric calibration on the infrared photoelectric system to be measured and obtain response gain G 0 And a response bias h det1 And h det2 ;
Obtaining the current ambient temperature T amb0 Raising the black body temperature to T 1 At integration time t 0 Next, an image h (t) is acquired 0 ,T 1 ,T amb0 );
Continuing to raise the temperature of the black body to T 2 At integration time t (t ≠ t) 0 ) Next, an image h (T, T) is acquired 2 ,T amb0 );
According to the formulaCalculating the stray radiation response coefficient G of the infrared photoelectric system to be detected stray Wherein, L (T) 1 )、L(T 2 ) Respectively is the temperature T 1 And T 2 The black body standard radiance, L (T) amb0 ) Is T amb0 Internal stray radiation of the infrared photoelectric system to be detected;
when the ambient temperature is T amb When it is waited forMethod for measuring internal stray radiation L (T) of infrared photoelectric system amb ) Comprises the following steps:
optionally, the adjusting the parallel alignment of the infrared optoelectronic system to be measured and the black body is specifically,
and adjusting the central line of an infrared detector in the infrared photoelectric system to be detected to penetrate through the geometric center of the black body.
Optionally, when the infrared photoelectric system to be measured is aligned in parallel with the black body, the effective radiation surface of the black body completely covers the main aperture of the infrared photoelectric system to be measured.
Optionally, the blackbody is disposed on a measuring device for dispersive radiation inside the infrared optoelectronic system to be measured.
Optionally, the measuring device includes a bottom plate, and the bottom plate is a vehicle carrying structure provided with wheels.
A second aspect of the embodiments of the present invention provides a device for measuring internal dispersion radiation of a large-aperture infrared optoelectronic system, where the device includes:
the device comprises a base plate, a black body arranged on the base plate and a first supporting structure used for supporting an infrared photoelectric system to be tested;
during measurement, the infrared photoelectric system to be measured is placed on the first supporting structure, and the position of the infrared photoelectric system to be measured is adjusted to be aligned with the position of the black body in parallel;
changing the temperature of the black body to perform radiometric calibration on the infrared photoelectric system to be tested to obtain a response gain G 0 And a response bias h det1 And h det2 ;
Obtaining the current ambient temperature T amb0 Raising the black body temperature to T 1 At integration time t 0 Next, an image h (t) is acquired 0 ,T 1 ,T amb0 );
Continuing to raise the temperature of the black body to T 2 At integration time t (t ≠ t) 0 ) At the bottom, adoptSet image h (T, T) 2 ,T amb );
According to the formulaCalculating the stray radiation response coefficient G of the infrared photoelectric system to be detected stray Wherein, L (T) 1 )、L(T 2 ) Are respectively the temperature T 1 And T 2 Internal stray radiation of the black body, L (T) amb0 ) Is T amb0 Internal stray radiation of the infrared photoelectric system to be detected;
when the ambient temperature is T amb In time, the stray radiation L (T) inside the infrared photoelectric system to be measured amb ) Comprises the following steps:
optionally, when the position of the infrared photoelectric system to be measured is aligned in parallel with the position of the black body, the effective radiation surface of the black body completely covers the main aperture of the infrared photoelectric system to be measured.
Optionally, the bottom plate is a vehicle carrying structure provided with wheels.
Optionally, the adjusting the parallel alignment of the infrared optoelectronic system to be measured and the black body is specifically,
and adjusting the central line of an infrared detector in the infrared photoelectric system to be detected to penetrate through the geometric center of the black body.
Optionally, the black body is disposed on a second support structure, and the infrared optoelectronic system to be tested is aligned in parallel with the position of the black body by adjusting the first support structure or/and the second support structure.
According to the method for measuring the internal dispersion radiation of the large-caliber infrared photoelectric system, the stray radiation response coefficient of the system is obtained by a standard extended source calibration method, and then the internal stray radiation of the infrared photoelectric system at different temperatures is measured.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention to the proper form disclosed herein. It is obvious that the drawings in the following description are only some embodiments, and that for a person skilled in the art, other drawings can be derived from them without inventive effort. In the drawings:
FIG. 1 is a schematic flow chart of a method for measuring internal dispersion radiation of a large-aperture infrared optoelectronic system according to the present invention;
FIG. 2 is a schematic diagram illustrating the principle of a method for measuring the internal dispersion radiation of a large-aperture infrared optoelectronic system according to an embodiment of the present invention;
fig. 3 is a schematic diagram of a device for measuring internal dispersion radiation of a large-aperture infrared optoelectronic system according to an embodiment of the present invention.
Detailed Description
The technical problems solved, the technical solutions adopted and the technical effects achieved by the embodiments of the present invention are clearly and completely described below with reference to the accompanying drawings and the specific embodiments. It should be apparent that the described embodiments are only a few embodiments of the present application, and not all embodiments. All other equivalent or obviously modified embodiments obtained by a person skilled in the art on the basis of the embodiments in the present application fall within the scope of protection of the present invention without inventive step. The embodiments of the invention can be embodied in many different ways as defined and covered by the claims.
It should be noted that in the following description, numerous specific details are set forth in order to provide an understanding. It may be evident, however, that the subject invention may be practiced without these specific details.
It should be noted that, unless explicitly defined or conflicting, the embodiments and technical features in the present invention may be combined with each other to form a technical solution.
Referring to fig. 1, the method for measuring internal dispersion radiation of a large-aperture infrared optoelectronic system of the present invention includes the following steps:
step S101, after the position of the infrared photoelectric system to be measured and a black body are adjusted to be aligned in parallel, the temperature of the black body is changed so as to carry out radiometric calibration on the infrared photoelectric system to be measured and obtain response gain G 0 And a response bias h det1 And h det2 。
Fig. 2 shows a measurement schematic diagram of the present application, and fig. 3 is a device to which the measurement method of the present application is applied, the measurement device including: the device comprises a bottom plate 06, a black body 01 arranged on the bottom plate and a first supporting structure 08 for supporting an infrared photoelectric system 03 to be tested; the bottom plate 06 is a vehicle carrying structure provided with wheels.
During measurement, the infrared photoelectric system to be measured is placed on the first support structure 08, and the position of the infrared photoelectric system to be measured is adjusted to be aligned with the position of the black body in parallel; further, the center line of the infrared detector 04 in the infrared photoelectric system 03 to be measured is adjusted to pass through the geometric center of the black body 01. The blackbody is arranged on the second supporting structure 02, the infrared photoelectric system 03 to be measured is aligned to the blackbody 01 in parallel by adjusting the first supporting structure 08 or/and the second supporting structure 02, and the measuring device is further provided with a temperature sensor 07 for detecting the temperature of each part in the measuring process.
The positions of the infrared photoelectric system and the black body in fig. 3 are adjusted to make the two parallel and aligned, and the effective radiation surface of the black body completely covers the main caliber of the infrared photoelectric system. By using the continuous change of the temperature of the black body, the response gain G of the system is obtained by the radiometric calibration of the infrared photoelectric system 0 And a response bias h det1 And h det2 In this process, there are records in the prior art, and no further description is given here.
Step S102, obtaining the current environment temperature T amb0 Raising the black body temperature to T 1 At integration time t 0 Next, image h (t) is acquired 0 ,T 1 ,T amb0 )。
Step S103, continuing to raise the temperature of the black body to T 2 At integration time t (t ≠ t) 0 ) Next, an image h (T, T) is acquired 2 ,T amb0 )。
In the above steps, the current ambient temperature T is obtained amb0 Then the black body is heated up to T 1 Black body temperature is stable at integration time t 0 Next, an image h (t) is acquired 0 ,T 1 ,T amb0 )。
Continuously raising the temperature of the black body to T 2 The blackbody temperature is stable, at integration time t (t ≠ t) 0 ) Next, image h (T, T) is again acquired 2 ,T amb0 )。
Step S104, calculating a stray radiation response coefficient G of the infrared photoelectric system to be tested according to a specified formula stray 。
Wherein the above-specified formula isL(T 1 )、L(T 2 ) Respectively is the temperature T 1 And T 2 The standard radiance of the black body, L (T) amb0 ) Is T amb0 And the internal stray radiation brightness of the infrared photoelectric system to be detected is measured.
Step S105, when the environment temperature is T amb According to said stray radiation response coefficient G stray The internal stray radiation at the current temperature is calculated.
Specifically, the internal stray radiation L (T) of the infrared photoelectric system to be measured amb ) Comprises the following steps:
according to the basic principle of infrared radiation measurement in the embodiment provided by the application, the method comprises the following steps:
wherein G is 0 For the response gain of the infrared photoelectric system, h det1 For system bias related to integration time, h det2 The system is biased independent of the integration time. L (T) 1 )、L(T 2 ) Respectively is the temperature T 1 And T 2 The standard radiance of the black body, L (T) amb0 ) Is T amb0 And obtaining the internal stray radiation brightness of the infrared photoelectric system to be detected by calibration of the system.
The above images are combined to obtain the response coefficient G of the system in stray radiation stray ;
If the ambient temperature changes to T amb Internal stray radiation L (T) amb ) Comprises the following steps:
thus, stray radiation of the large-aperture infrared photoelectric system is obtained.
The stray radiation response coefficient is obtained under the conditions of radiometric calibration and ambient temperature, and the stray response coefficient of the system is obtained without changing the ambient temperature. The problem that stray radiation measurement cannot be carried out in a temperature control box due to the fact that a large-caliber infrared photoelectric system is large in size is effectively solved.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to the related descriptions of other embodiments for parts that are not described or illustrated in a certain embodiment.
The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (10)
1. A method for measuring stray radiation in a large-caliber infrared photoelectric system is characterized by comprising the following steps:
after the positions of the infrared photoelectric system to be measured and the black body are adjusted to be aligned in parallel, the temperature of the black body is changed so as to carry out radiometric calibration on the infrared photoelectric system to be measured and obtain response gain G 0 And in response to an offset h det1 And h det2 ;
Obtaining the current ambient temperature T amb0 Raising the black body temperature to T 1 At integration time t 0 Next, an image h (t) is acquired 0 ,T 1 ,T amb0 );
Continuing to raise the temperature of the black body to T 2 At integration time t (t ≠ t) 0 ) Next, an image h (T, T) is acquired 2 ,T amb0 );
According to the formulaCalculating the stray radiation response coefficient G of the infrared photoelectric system to be detected stray Wherein, L (T) 1 )、L(T 2 ) Respectively is the temperature T 1 And T 2 The standard radiance of the black body, L (T) amb0 ) Is T amb0 The internal stray radiation brightness of the infrared photoelectric system to be detected is measured;
when the ambient temperature is T amb In time, the stray radiation L (T) inside the infrared photoelectric system to be measured amb ) Comprises the following steps:
2. the method according to claim 1, wherein the adjusting the position of the infrared optoelectronic system to be measured and the black body to be aligned in parallel is specifically,
and adjusting the central line of an infrared detector in the infrared photoelectric system to be detected to penetrate through the geometric center of the black body.
3. The measurement method according to claim 1, wherein when the infrared optoelectronic system to be measured is aligned in parallel with a black body, an effective radiation surface of the black body completely covers a main aperture of the infrared optoelectronic system to be measured.
4. A method as claimed in any one of claims 1 to 3, characterized in that said black body is arranged on a measuring device of the dispersed radiation inside the infrared optoelectronic system to be measured.
5. The method of claim 4, wherein the measuring device comprises a base plate, and the base plate is a vehicle carrying structure provided with wheels.
6. A device for measuring stray radiation in a large-aperture infrared optoelectronic system, the device comprising:
the device comprises a bottom plate, a black body arranged on the bottom plate and a first supporting structure used for supporting an infrared photoelectric system to be tested;
during measurement, the infrared photoelectric system to be measured is placed on the first supporting structure, and the position of the infrared photoelectric system to be measured is adjusted to be aligned with the position of the black body in parallel;
changing the temperature of the black body to perform radiometric calibration on the infrared photoelectric system to be tested to obtain a response gain G 0 And a response bias h det1 And h det2 ;
Obtaining the current ambient temperature T amb Raising the black body temperature to T 1 At integration time t 0 Next, an image h (t) is acquired 0 ,T 1 ,T amb0 );
Continuing to raise the temperature of the black body to T 2 At integration time t (t ≠ t) 0 ) Next, collect the pictureLike h (T, T) 2 ,T amb0 );
According to the formulaCalculating the stray radiation response coefficient G of the infrared photoelectric system to be detected stray Wherein, L (T) 1 )、L(T 2 ) Are respectively the temperature T 1 And T 2 The radiation standard radiance of the black body, L (T) amb0 ) Is T amb0 Internal stray radiation of the infrared photoelectric system to be detected;
when the ambient temperature is T amb In time, the stray radiation L (T) inside the infrared photoelectric system to be measured amb ) Comprises the following steps:
7. the measurement device according to claim 6, wherein when the infrared optoelectronic system under test is aligned in parallel with a black body, an effective radiation surface of the black body completely covers a main aperture of the infrared optoelectronic system under test.
8. The measuring device of claim 7, wherein the base plate is a cart structure provided with wheels.
9. The measurement device according to claim 7, wherein the adjusting of the parallel alignment of the infrared optoelectronic system to be measured and the black body is,
and adjusting the central line of an infrared detector in the infrared photoelectric system to be detected to penetrate through the geometric center of the black body.
10. A measuring device as claimed in claim 7, characterized in that the black body is arranged on a second support structure, the first support structure or/and the second support structure being adjusted in order to align the infrared optoelectronic system to be measured parallel to the position of the black body.
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