SU1486783A1 - Automated goniometer for measuring angles of polyhedral prisms - Google Patents

Description

The invention relates to measuring equipment. The aim of the invention is to improve the measurement accuracy by increasing the signal-to-noise ratio of the video signal. Multifaceted prism 22 mounted on the subject table 4, rotates together

with a rotary platform 1 with a drive 2. A photodetector mounted in autocollimator 5 generates signals, the time interval between which is remembered by pulses generated by a ring laser 3. The result is a signal processing signal. The linear charge coupled device installed in the autocollimator 5 generates video signals from the image of the diaphragm located in the autocollimator 5. The beginning of the time interval is determined by the signal formed by the imaging unit 15. The end of the time interval is determined by the maximum of the video signal taken from the linear charge coupled device. A time interval proportional to the pyromidality of the faces of the multifaceted prism 22 is recorded by the signal processing unit 21. A synchronizer 17 is started through the first adder 16. The output register of the charge-coupled linear device is reset through the second adder 20. The time interval at which the output register of the charge-coupled linear device occurs and the subsequent start of the clock generator 17 is set by the reset unit 18. The blocking block 19 blocks the start of the synchronization of the magnitude of the right angles of the multifaceted generator 17 by means of a signal

prism 22 is recorded by the unit

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The invention relates to measuring equipment and can be used to measure the flat angles and lyramidality of multifaceted prisms.

The aim of the invention is to improve the measurement accuracy by increasing the signal-to-noise ratio of the video signal.

FIG. 1 shows a functional diagram of the goniometer; Fig.2 autocollimator in the focal plane; in fig. 3 - timing diagrams of signals generated at the outputs of individual nodes of the device.

Goniometer contains a turntable 1 with a drive 2 and a rotation speed sensor, made in the form of an annular laser 3, an object table 4, mechanically connected with the turntable 1; autocollimator 5, made in the form of an illuminator 6, lens 7, slit diaphragms 8 and 9, located in the focal plane of the lens 7 perpendicular and parallel to the axis of rotation of the turntable 1, analyzing aperture 10, parallel to the axis of rotation of the turntable 1, of the photodetector 11 located along the course of the reflected rays passing through the diaphragm mu 10 of the linear charge coupled device (CCD) 12, whose photosensitive areas are located parallel to the axis of rotation of the turntable 1; control unit 13, made in the form of a delay unit 14, the input of which is connected to the output of the photodetector 11 of the autocollimator 5, the driver. 15, the input of which is connected to the output of the delay node 14, the first adder 16, the first input of which is connected to the output of the driver 15, the synchronizer 17, the first input of which is connected to the output of the first adder · 16, <the first output is connected to the input of the CCD 12 of the autocollimator 5, node zeroing, the input of which is connected to the second output of the synchronous generator 17, node 19 of the lock, the first input of which is connected to the output of node 18 zeroing, the second input is connected to the output of node 14 of the delay, the output is connected to the second input of the first adder 16, the second adder 20, p The left input is connected to the output of the photonribmeric 11 of the autocollimator 5, the second input is connected to the output of the nulling node 18, the output is connected to the second input of the clock generator 17, the signal processing unit 21, the inputs of which are connected to the output of the ring laser 3, the output of the photoreceiver 11 of the autocollimator 5, output respectively CCD 12 autocollimator 5, the output of the imaging unit 15 and the output of the node 18 zeroing.

The flat angles and the pyramid of the multifaceted prism 22 mounted on the object table 4 are measured.

Goniometer works as follows.

When the rotary platform 1 is rotated by the actuator 2, pulses are generated at the exit of the ring laser 3, the frequency of which is proportional to the angular velocity of rotation of the rotary platform 1. The illuminator 6 forms light beams passing through the diaphragms 8.9 and the lens 7. When the face of the polyhedral prism 22 is located perpendicular to the optical axis autocollimator 5, the beams of light pass through the diaphragm 10 and at the output of the photodetector 11 a signal is generated that arrives at the signal processing unit 21. With the location of the next facet of a multifaceted prism 22 perpendicular to the optical axis of the autocollimator 5, a signal is generated at the output of the photoreceiver 11 (Fig. 3).

The time interval between the signals generated by the photodetector 11 is filled with pulses taken from the ring laser 3, the number of which calculates the magnitude of the planar angles of the multifaceted prism 22. The signal taken from the photodetector 11 enters the delay unit 14, which generates a delay signal after which The image 8 'of the diaphragm 8 is projected onto the photosensitive sites of the CCD 12 (FIG. 3, and ₁₄ ).

On the falling edge of the signal generated by the delay node 14, the driver 15 generates a pulse that passes through the first adder 16 and starts the sikh generator 17 (FIG. 3, C ₁₅ ). The clock generator 17 generates the polling signals of the CCD 12, i.e. exposure pulses (fig.Z and _Pi ), charge transfer pulses (fig.Z,

and read clock

information from the shift register

CCD 12 (Fig. 3, C _{ΙΊ 8} ). CCD 12 generates a video signal, the temporary position of which is associated with the value of PI1486783

ramidalnosti multifaceted reflecting face of the prism 22. The signal processing unit 21 measures the time interval, the beginning of which is determined by the signal generated by generator 15, the end of the time interval determined by the maximum threshold or the video taken from the CCD 12. The amount of time interval is proportional to the shaft ₁ multifaceted pyramidal prism 22

The signal generated by the photodetector 11 enters through the second adder 20 to the synchronous generator 17, ensuring ₍ zeroing the output register of the CCD 12 at the beginning of each measurement cycle of the pyramidal value of the reflecting face of a multifaceted prism 22. The nulling node 18 is reset by signals received from the synchro generator 17 , periodically generates signals to reset the output register of the CCD 12 (FIG. 3,

4 ,.), which pass to the input of syn • P

of the generator 17 through the second adder 20. The pulses generated by the node

18 zeroing, in the signal processing unit 21, the nodes that measure the time interval associated with the pyramid of faces are reset; multifaceted prism 22, to its original state. Impulses generated by zeroing node 18 pass through the node

19, the first adder 16 and the start of the sync generator 17. The signal generated by the delay unit 14 enters the input of the blocking unit 19 and blocks the passage of the signals generated by the zeroing unit 18.

Thus, on the CCD 12, an informational video signal is formed at the moments of projection of the image 8 'of the diaphragm 8 onto the photosensitive areas of the CCD 12.

The use of the device allows to increase the measurement accuracy by reducing the non-information noise and background components of the video signal taken from the CCD 12, due to the introduction of a fixed optimal charge accumulation time.

Claims (1)

Claim Automated goniometer for measuring angles of multifaceted prisms containing a turntable with a drive and a rotation speed sensor made in the form of a ring laser, an autocollimator made in the form of an illuminator and a lens with two slit diaphragms installed in its focal plane, which are perpendicular to one another and one of them is perpendicular to the axis of rotation of the turntable, analyzing the diaphragm with a photodetector, an additional photodetector, made in the form of a linear device with charge coupling, the light sensitive areas of which are parallel to the axis of rotation of the turntable, signal processing unit whose inputs are connected to a photodetector, a ring laser, the output of a linear charge coupled device, a control unit that distinguishes — in order to improve measurement accuracy, the control unit is designed as a delay unit, the input of which is connected to a photodetector, a driver, the input of which is connected to the output of the delay unit, the output of the driver is connected to the synchronizing input of the unit processing the signal, the first adder, the first input of which is connected to the output of the driver, the synchronous generator, the first input of which is connected to the output of the first adder, the first output is connected to the linear charge coupled device, the zeroing unit, the input of which is connected to the second output of the synchronous generator, the output to the zeroing the input of the signal processing unit, blocking node, the first input of which is connected to the output of the zeroing node, the second input is connected to the output of the delay node, the output is connected to the second input of the first adder, the second total Ora, the first and second inputs of which are connected respectively to the input of the delay node and the output of the zeroing node, the output is connected to the second input of the clock generator. 1486783 n 21 ι? / τ? 17 ζ-