SU1412005A1 - Device for measuring parameters of scanning systems of thermovisors - Google Patents

Abstract

The invention relates to engineering. Tv The purpose of the invention is to increase the measurement accuracy. The device contains shaper 1 optical. radiation consisting of a source 2 of collimated optic. radiation and optical fiber 3, micro-lens 4, diaphragm 5, optical mechanical. W 6 scanner, metallic. screen 9. Introduced Mr. 7 modulating signals, optical. modulator 8, linear motion sensor 10, A / D converter II, multiplexer (M) 12, frequency converter 13 — code, time selector 14, multiplier 15. A parallel beam of light rays from source 2 is guided by light guide 3 to modulator 8, to changes the intensity of the light flux at intervals of time determined by the measurement accuracy, specified by the frequency of g-7 pulses. The modulated light flux enters the micro objective 4 and through the diaphragm 5 the scanner 6, the sensor 10 and the stationaryand its movable contacts are located in the center of the reference light marks, between which the velocity is measured and its nonlinearity is estimated. The ADC II receives a signal, then to the input M 12, through which the digital signals pass to the multiplier 15, which calculates the scan rate of the scanner 6. 2 Il. S (l oo o o jv

Description

The invention responds to television engineering and can be used to measure the parameters of imaging scanning systems.

The purpose of the invention is to improve the measurement accuracy.

Fig. 2 shows the structural electrical circuit of the device for

10, and the fixed and movable contacts are in the center of the reference light marks, between which you can measure the speed and evaluate its nonlinearity (usually at the beginning and end of the selected line). Depending on the linear distance between the contacts of the sensor 10 to the input of the analog-to-digital

measurements of the parameters of the scanning sy-jg converter 11 are supplied by the thermal imagers; Fig, 2 is a diagram of the generator of modulating signals.

A device for measuring the parameters of scanning systems of thermal imagers (Fig. 1) contains a shaper 1 of optical radiation consisting of a source 2 of collimated optical radiation and a fiber light guide 3, a micro-lens 4, a diaphragm 5, an optical-mechanical scanner (OMC) 6, 20 modulating signal generator 7, optical modulator 8, metric screen 9, linear displacement sensor 0, analog-to-digital converter II, multiplexer 12, frequency converter 13 - code, time selector 14, multiplier 15,

The modulating signal generator 7 (FIG. 2) contains a clock pulse generator 16, a match block 17, a pulse counter 18, a pulse frequency divider 19, a match block 20, a counter 21, horizontal sync pulses, a pulse frequency divider 22

the signal that he digitizes. This signal is fed to the input of the multiplexer 12, to another input of which the digital value of the signal from the output of the converter 1 is received - the code corresponding to the selected frequency of placement of the reference light marks. The signal of the time selector 14 permits the passage of digital signals through mu plexor 12, which correspond to the value of the linear distance between the marks and their frequency, on the input of the multiplier 15, the Last unit computes the scan rate OMC 6 ,.

The generator 7 modulating the signal operates as follows.

Horizontal sync pulses at the input of the block 17 matches, allowing the passage of pulses from the generator 16 clock pulses to the input of the counter 18, depending on the division factor of the divider 1

The device operates as follows ob-, 5 through a block of 20 matches, pulses are received at the input of the optical modulator 8 with a certain frequency. At the same time, the horizontal sync pulses are fed to the input of the counter 21, Divider 22 allows you to select the desired frequency of the line signals.

at once.

A parallel beam of light rays from the source 2 of the former 1 is guided by a flexible optical fiber 3 to the optical modulator 8, which varies the intensity of the light flux through time intervals determined by the required measurement accuracy of the modulating signals 7, the modulated luminous flux enters micro-lens 4, from which a converging beam of rays emerges, which through the aperture 5 installed in the focal plane of micro-lens 4 (the diameter of the hole in the aperture 5 corresponds to the size of the sensitive area of the radiation receiver falling into the optical system OMC 6, which scans the light beam along the line and frame, creating a raster image on the metric screen 9. Date 9

11 transducer enters

the signal that he digitizes. This signal is fed to the input of the multiplexer 12, to the other input of which the digital value of the signal from the output of the Converter 13 is fed - the code corresponding to the selected frequency of the reference light marks. The signal of the time selector 14 allows digital signals to pass through the multiplexer 12, which correspond to the value of the linear distance between the marks and their frequency, to the input of the multiplier 15. The latter calculates the scan rate OMC 6 ,.

The generator 7 of the modulating signal operates as follows.

Lower-order sync pulses are fed to the input of the block 17 of coincidences, thereby allowing the passage of pulses from the generator of 16 clocks to the input of counter 18, depending on the division factor of the divider 19

, 5 through block 20 matches to the input of op5

Q,

0

Tactical modulator 8 receives pulses with a certain frequency. At the same time, the horizontal sync pulses are fed to the input of the counter 21, Divider 22 allows you to select the desired frequency of the line signals.

Changing the pulse frequency from the outputs of dividers 19. and 22 at the output of the modulating signal generator 7, whose operation is synchronized with the OMS 6, can be changed in accordance with the required measurement accuracy and can be changed on the metric screen 9 at desired intervals. line frequency i. By estimating the magnitude of the scanning speed at the beginning and at the end of the selected line, one can also determine the nonlinearity coefficient of the line scan. The formula of the invention

Device for measuring parameters of scanning imagers.

containing an optical radiation shaper, made in the form of consecutive sources of collimated optical radiation and a fiber light guide, as well as a micro lens and a diaphragm installed in the focal plane of the micro lens, an optical-mechanical scanner (OMS) and a metric screen, which is in order to improve the measurement accuracy, an optical modulator, installed between the optical radiation shaper and the micro lens, is introduced, connected in series by a modulating generator x signals input Ko

412005

Secondly, it is connected to the output of horizontal sync pulses of an optomechanical one. scanner, frequency converter - code, multiplexer and multiplier, serially connected linear displacement sensor placed on a metric screen, and analog-to-digital converter, the output of which

JQ is connected to the signal input of the multiplexer, as well as a time selector, the output of which is connected to the control input of the multiplexer, p {5 and the output of the modulating signal generator 15 is connected to the control input of the optical modulator.

Claims (1)

Claim A device for measuring the parameters of scanning systems of thermal imagers, comprising an optical radiation shaper made in the form of a sequentially collimated optical radiation source and a fiber waveguide, as well as a micro lens and aperture mounted in the focal plane of a micro lens, an optical-mechanical scanner (OMS) and a metric screen, о characterized in that, in order to increase the accuracy of measurements, an optical modulator is introduced, installed between the optical radiation shaper and with a lens connected in series with the output of the horizontal sync pulses of the optical-mechanical scanner, a frequency-code converter, a multiplexer and a multiplier connected in series with a linear displacement sensor located on a metric screen, and an analog-to-digital converter, the output of which is connected to the signal input of the multiplexer, and also a time selector, the output of which is connected to the control input of the multiplexer, and the output of the modulating signal generator15 is connected to the control yayuschim input optical modulator. modulating signal torus, input of FIG. 2