CN104050356A - Scan rate evaluation method for TDI (Transport Driver Interface) infrared detector scanning imaging system - Google Patents
Scan rate evaluation method for TDI (Transport Driver Interface) infrared detector scanning imaging system Download PDFInfo
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Abstract
The invention relates to a scan rate evaluation method for a TDI (Transport Driver Interface) infrared detector scanning imaging system. Based on the positional deviation of odd and even parity bits of a detector in targeted images output by the imaging system, the matching situation of the scan rate and other parameters of the system is quantitatively analyzed, so that the scanning control parameters are adjusted, and the requirements of the imaging system are met. In addition, in order to evaluate the scan rate of the entire scanning field, a method according to which the imaging system can rotate around a rotating shaft of a scanning lens by an adjusting mechanism is provided, so that the detection and evaluation of the scan rate of the entire field are realized. The method provided by the invention has the advantages of simple evaluation method, flexibility, high testing precision and the like, and can be used for evaluating the scan rate in the TDI infrared detector scanning imaging system.
Description
Technical field
The invention belongs to aerospace optical remote sensing technical field, relate to a kind of TDI of being applicable to infrared eye scanning imaging system sweep speed appraisal procedure.
Background technology
In space optical remote sensor, advantage that scanning imaging system has that observation visual field is large, spectral coverage is wide etc., but scanning mechanism is complicated, and the inaccurate or variation of sweep speed can cause pattern distortion, affect picture element.In TDI infrared eye scanning imaging system, sweep speed and system focal length, integral time parameter mate particularly outstanding.
In scanning imaging system in the past, generally according to the independent test data assessment of scanning mechanism sweep speed, and in imaging system, do not assess.Scanning mechanism carries out sweep speed design according to scanning imaging system design parameter, adopts linearity tester to carry out sweep speed and linearity test thereof.The conventional photoelectric measuring horn cupping test scan speed of current linearity tester and the linearity thereof, adopt and take ccd detector as basic image measuring method.On the focal plane of parallel light tube, place a slit target, by integrating sphere, thrown light on, after parallel light tube collimation, form directional light.Scanning mechanism is placed in parallel light path, scanning mirror and directional light angle at 45 °, and scanning mirror is turned back directional light 90 ° and is entered CCD camera.When scanning mirror swings α, the emergent light direction of scanning mirror changes 2 α, according to the position of speck on CCD camera, can carry out measurement of angle.The method is only applicable to sweep speed and the linearity assessment thereof of scanning mechanism.
After imaging system has been debug, may there is deviation with design load in its focal length and detector integrates time parameter.In order to make sweep speed and imaging system focal length, integral time parameter matching, need a kind of method of assessing sweep speed on scanning imaging system.
Summary of the invention
Technology of the present invention is dealt with problems: overcome the deficiencies in the prior art, a kind of TDI infrared eye scanning imaging system sweep speed appraisal procedure is proposed, can assess the sweep speed of the full visual field of scanning imaging system, and adjust scan control parameter with this, solve the mismatch problem of sweep speed and system focal length, integral time parameter, raising image quality.
The technology of the present invention solution: a kind of TDI infrared eye scanning imaging system sweep speed appraisal procedure, performing step is as follows:
(1) adopt two-point method to carry out nonuniformity correction to four bar target images of scanning imaging system output, target image edge to n unit infrared eye in every bar target image, part and part is all chosen dark fringe 5～12 row, bright fringes 5～12 row from bright fringes to dark fringe image from dark fringe to bright fringes, carry out 10 times interpolation by cubic spline function to data to the data of choosing; Target image edge to n+1 unit infrared eye, part and part is all chosen dark fringe 5～12 row, bright fringes 5～12 row from bright fringes to dark fringe image from dark fringe to bright fringes, carry out 10 times interpolation by cubic spline function to data to the data of choosing;
(2) to after proofreading and correct in step (1) four bar target images, calculate the average of every bar bright fringes view data, calculate the average of every bar dark fringe view data; The average of every bar dark fringe and bright fringes image is asked to difference, get difference 1/2 and obtain every bar target image half-power point image DN value with dark fringe average summation;
(3) to the data after every bar target image interpolation in step (1) by the method for searching, search the first infrared eye of n unit and n+1 columns K corresponding to half-power point image DN value place in step (2)
nand K
n+1; Calculating K
n+1with K
nabsolute value difference Δ K;
(4) by the Δ K in step (3), calculate sweep speed deviation, computing formula is as follows:
In formula (1): △ V: sweep speed deviation;
V: nominal sweep speed;
△ K: detector odd even unit picture position deviation;
D: the ratio of the strange unit of detector and even first spacing and imaging system sampling interval;
The sweep speed relative deviation that calculates scanning imaging system according to formula (1), computing formula is as follows:
When △ K is 0, △ V is 0, and now sweep speed and system focal length, integral time, parameter was mated completely; When △ K is while being non-zero, △ V is also non-zero, sweep speed and system focal length, integral time parameter Incomplete matching;
(5) utilize the part that four bar targets at every turn can only test scan visual field, for the sweep speed to whole scanning field of view is assessed, utilize adjusting mechanism to make imaging system around scanning mirror rotating shaft rotation, make different scanning field of view can aim at the visual field, center of parallel light tube.
Adjusting mechanism in described step (5) is a rotation platform, and scanning imaging system is installed on rotation platform, and the rotating shaft of rotation platform and scanning mirror rotating shaft are coaxial, utilizes hand crank to realize rotation platform and rotates around the shaft.
The present invention's advantage is compared with prior art:
(1), for the feature of TDI infrared eye scanning imagery, propose a kind ofly based on scanning imaging system, sweep speed to be detected.According to testing result, adjust scan control parameter, improve scanning imaging system image quality.
(2) the sweep speed appraisal procedure based on scanning imaging system, strange, the even first position deviation of quantitative test, measuring accuracy is better than 0.1 pixel, can realize in imaging system sweep speed is carried out to high precision assessment.
(3) by adjusting mechanism, can realize the sweep speed of different visual fields is carried out to comprehensive assessment.The limitation that can only check local visual field scanning speed when the method has overcome laboratory imaging in the past, can solve the evaluation problem of full-field scanning speed and system focal length, integral time parameter matching performance;
(4) this method have high precision, simply, advantage flexibly, the assessment that can be used for solving sweep speed in TDI infrared eye scanning imaging system.
Accompanying drawing explanation
Fig. 1 is realization flow figure of the present invention;
Fig. 2 is that scan control parameter optimization front target is marked on a map;
Fig. 3 is the odd even position deviation figure of unit in half-power point place before scan control parameter optimization;
Fig. 4 is target figure after scan control parameter optimization;
Fig. 5 is the position deviation figure of half-power point place odd even unit after scan control parameter optimization.
Embodiment
The present invention is a kind of TDI infrared eye scanning imaging system sweep speed appraisal procedure.After imaging system completes and debugs, real system parameter and design load have deviation, cause sweep speed and system focal length, integral time parameter not mated, and affect image quality.For this reason need to be in the enterprising line scanning rate test of imaging system.Test philosophy is utilize intrinsic position deviation between strange, the even unit of detector to carry out scan rate measurement, thereby whether assessment sweep speed and the linearity thereof to meet imaging requirements.Utilize image capturing system and adjusting mechanism to gather imaging system at four bar target images of each place, visual field output, utilize dedicated processes software to carry out nonuniformity correction to the target image of full visual field, and the position deviation of strange, the even first image of quantitative test Ge Gan target image edge, according to position deviation, calculate sweep speed and nonlinearity thereof, and then adjust scan control parameter, eliminate the position deviation of strange, even first image.
The strange unit of certain model TDI infrared eye is 481.4um with even first intrinsic spacing, and imaging system sampling interval is 16.6um, so the ratio d of detector odd even unit's spacing and imaging system sampling interval is 29.
As shown in Figure 1, the concrete implementation step of the present invention is as follows:
(1) adopt two-point method to carry out nonuniformity correction to four bar target images of scanning imaging system output.As shown in Figure 1, when Fig. 2 is sweep speed and other parameter Incomplete matching of system, i.e. scan control parameter optimization front target image, this target image is the image after nonuniformity correction.To this image target image edge to n unit infrared eye in every bar target image, part and part is all chosen dark fringe 12 row, bright fringes 12 row from bright fringes to dark fringe image from dark fringe to bright fringes, carry out 10 times interpolation by cubic spline function to data to the data of choosing; Target image edge to n+1 unit infrared eye, part and part is all chosen dark fringe 12 row, bright fringes 12 row from bright fringes to dark fringe image from dark fringe to bright fringes, carry out 10 times interpolation by cubic spline function to data to the data of choosing; As shown in Figure 3, in figure, 4 figure are respectively columns after every bar target image edge n unit and 10 times of interpolation of the first infrared eye of n+1 and the graph of a relation of gradation of image value.In figure, A, B curve are respectively n unit and n+1 unit's infrared eye target image edge, and as can be seen from the figure infrared eye odd even unit image bit is equipped with larger deviation.
(2) to after proofreading and correct in step (1) four bar target images, calculate the average of every bar bright fringes view data; Calculate the average of every bar dark fringe view data; The average of every bar dark fringe and bright fringes image is asked to difference, get difference 1/2 and obtain every bar target image half-power point image DN value with dark fringe average summation;
(3) to the data after every bar target image interpolation in step (1) by the method for searching, search the first infrared eye of n unit and n+1 columns K corresponding to half-power point image DN value place in step (2)
nand K
n+1; Calculating K
n+1with K
nabsolute value difference Δ K; Half-power point odd even unit position deviation maximal value is 0.7 pixel.
(4) by the Δ K in step (3), calculate sweep speed deviation, computing formula is as follows:
In formula (1): △ V: sweep speed deviation;
V: nominal sweep speed;
△ K: detector odd even unit picture position deviation;
D: the ratio of the strange unit of detector and even first spacing and imaging system sampling interval, value is 29.
The sweep speed relative deviation that can calculate scanning imaging system according to formula (1), computing formula is as follows:
(5) utilize the part that four bar targets at every turn can only test scan visual field, utilize adjusting mechanism to make imaging system around scanning mirror rotating shaft rotation, make different scanning field of view can aim at the visual field, center of parallel light tube, thereby carry out the assessment of full-field scanning speed.This adjusting mechanism is a rotation platform, and scanning imaging system is installed on rotation platform, and the rotating shaft of rotation platform and scanning mirror rotating shaft are coaxial, utilizes hand crank to realize rotation platform and rotates around the shaft.
(6) calculate strange, the even first position deviation in full visual field, utilize formula 2 can obtain the sweep speed relative deviation based on scanning imaging system.When half-power point odd even unit position deviation maximal value is 0.7 pixel.It is 2.4% that sweep speed and nominal sweep speed obtain relative deviation.According to test result adjustment, optimize scan control parameter, reduce strange, even first position deviation.As shown in Figure 4, Fig. 4 obtains target image after optimizing scan control parameter, and this target image is the image after nonuniformity correction.According to step (1), every bar target image edge is carried out to 10 times of interpolation, as shown in Figure 5, in figure, 4 figure are respectively columns after every bar target image edge n unit and 10 times of interpolation of the first infrared eye of n+1 and the graph of a relation of gradation of image value.In figure, A, B curve are respectively n unit and n+1 unit's infrared eye target image edge, and as can be seen from the figure infrared eye odd even unit image bit is equipped with less deviation, and in figure, 2 curves overlap substantially.According to step (2)～step (4), carry out the image half-power point position deviation computational analysis of odd even unit, half-power point odd even unit position deviation maximal value is 0.1 pixel, and it is 0.3% that sweep speed and nominal sweep speed obtain relative deviation.According to analysis result, can find out, the focal length of sweep speed and imaging system after scan control parameter optimization, integral time, parameter matching was good, had improved image quality.
The content not being described in detail in instructions of the present invention belongs to those skilled in the art's known technology.
Claims (2)
1. a TDI infrared eye scanning imaging system sweep speed appraisal procedure, is characterized in that performing step is as follows:
(1) adopt two-point method to carry out nonuniformity correction to four bar target images of scanning imaging system output, target image edge to n unit infrared eye in every bar target image, part and part is all chosen dark fringe 5～10 row, bright fringes 5～10 row from bright fringes to dark fringe image from dark fringe to bright fringes, carry out 10 times interpolation by cubic spline function to data to the data of choosing; Target image edge to n+1 unit infrared eye, part and part is all chosen dark fringe 5～10 row, bright fringes 5～10 row from bright fringes to dark fringe image from dark fringe to bright fringes, carry out 10 times interpolation by cubic spline function to data to the data of choosing;
(2) to after proofreading and correct in step (1) four bar target images, calculate the average of every bar bright fringes view data, calculate the average of every bar dark fringe view data; The average of every bar dark fringe and bright fringes image is asked to difference, get difference 1/2 and obtain every bar target image half-power point image DN value with dark fringe average summation;
(3) to the data after every bar target image interpolation in step (1) by the method for searching, search the first infrared eye of n unit and n+1 columns K corresponding to half-power point image DN value place in step (2)
nand K
n+1; Calculating K
n+1with K
nabsolute value difference Δ K;
(4) by the Δ K in step (3), calculate sweep speed deviation, computing formula is as follows:
In formula (1): △ V: sweep speed deviation;
V: nominal sweep speed;
△ K: detector odd even unit picture position deviation;
D: the ratio of the strange unit of detector and even first spacing and imaging system sampling interval;
The sweep speed relative deviation that calculates scanning imaging system according to formula (1), computing formula is as follows:
When △ K is 0, △ V is 0, and now sweep speed and system focal length, integral time, parameter was mated completely; When △ K is while being non-zero, △ V is also non-zero, sweep speed and system focal length, integral time parameter Incomplete matching;
(5) utilize the part that four bar targets at every turn can only test scan visual field, for the sweep speed to whole scanning field of view is assessed, utilize adjusting mechanism to make imaging system around scanning mirror rotating shaft rotation, make different scanning field of view can aim at the visual field, center of parallel light tube.
2. TDI infrared eye scanning imaging system sweep speed appraisal procedure according to claim 1, it is characterized in that: the adjusting mechanism in described step (5) is a rotation platform, scanning imaging system is installed on rotation platform, the rotating shaft of rotation platform and scanning mirror rotating shaft are coaxial, utilize hand crank to realize rotation platform and rotate around the shaft.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105758400A (en) * | 2016-02-15 | 2016-07-13 | 上海卫星工程研究所 | Extracting method for fixed star sensitive east and west parameters of stationary satellite imaging navigation and registration |
| CN106404179A (en) * | 2016-08-31 | 2017-02-15 | 天津津航技术物理研究所 | Infrared TDI detector bidirectional scanning characteristic-based real-time calibration method |
| CN106768349A (en) * | 2016-11-18 | 2017-05-31 | 天津津航技术物理研究所 | Adapt to the TDI scanning imaging system relative radiometric calibration methods of multichannel bidirectional output |
| CN107631801A (en) * | 2017-09-01 | 2018-01-26 | 天津津航技术物理研究所 | TDI detectors are in the inclined bearing calibration of optical axis orthogonal direction under a kind of static conditions |
| CN112261326A (en) * | 2020-09-01 | 2021-01-22 | 北京空间机电研究所 | Infrared remote sensor based on photon information digital accumulation overlong TDI |
| CN114295224A (en) * | 2021-11-30 | 2022-04-08 | 天津津航技术物理研究所 | Infrared TDI detector line frequency adjusting system and method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102466521A (en) * | 2010-11-12 | 2012-05-23 | 南京理工大学 | TDI (Time Delay Integration) scan imaging method for Snapshot type area array infrared detector |
-
2014
- 2014-04-08 CN CN201410138663.XA patent/CN104050356B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102466521A (en) * | 2010-11-12 | 2012-05-23 | 南京理工大学 | TDI (Time Delay Integration) scan imaging method for Snapshot type area array infrared detector |
Non-Patent Citations (3)
| Title |
|---|
| HANS NETTEN等: ""A fast scanner for fluorescence microscopy using a 2-D CCD and time delayed integration"", 《BIOIMAGING 2》 * |
| 吴宏圣: ""TDI CCD全景式航空相机的像移补偿误差分析"", 《光学精密工程》 * |
| 李军等: ""线阵TDI探测器成像中扫描速度偏差影响"", 《激光与红外》 * |
Cited By (11)
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| CN105758400A (en) * | 2016-02-15 | 2016-07-13 | 上海卫星工程研究所 | Extracting method for fixed star sensitive east and west parameters of stationary satellite imaging navigation and registration |
| CN105758400B (en) * | 2016-02-15 | 2018-08-03 | 上海卫星工程研究所 | Fixed statellite imaging based navigation be registrated fixed star sensitivity thing parameter extracting method |
| CN106404179A (en) * | 2016-08-31 | 2017-02-15 | 天津津航技术物理研究所 | Infrared TDI detector bidirectional scanning characteristic-based real-time calibration method |
| CN106404179B (en) * | 2016-08-31 | 2019-06-21 | 天津津航技术物理研究所 | A kind of real-time calibration method based on infrared TDI detector bilateral scanning characteristic |
| CN106768349A (en) * | 2016-11-18 | 2017-05-31 | 天津津航技术物理研究所 | Adapt to the TDI scanning imaging system relative radiometric calibration methods of multichannel bidirectional output |
| CN106768349B (en) * | 2016-11-18 | 2019-04-19 | 天津津航技术物理研究所 | Adapt to the TDI scanning imaging system relative radiometric calibration method of multichannel bidirectional output |
| CN107631801A (en) * | 2017-09-01 | 2018-01-26 | 天津津航技术物理研究所 | TDI detectors are in the inclined bearing calibration of optical axis orthogonal direction under a kind of static conditions |
| CN112261326A (en) * | 2020-09-01 | 2021-01-22 | 北京空间机电研究所 | Infrared remote sensor based on photon information digital accumulation overlong TDI |
| CN112261326B (en) * | 2020-09-01 | 2022-12-27 | 北京空间机电研究所 | Infrared remote sensor based on photon information digital accumulation overlong TDI |
| CN114295224A (en) * | 2021-11-30 | 2022-04-08 | 天津津航技术物理研究所 | Infrared TDI detector line frequency adjusting system and method |
| CN114295224B (en) * | 2021-11-30 | 2024-03-22 | 天津津航技术物理研究所 | System and method for adjusting line frequency of infrared TDI detector |
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