RU2366894C2 - Laser device for measurement of instability of spatial position of objects and detection of their shape deviation from linearity - Google Patents

Abstract

FIELD: physics, measurements.

SUBSTANCE: invention is related to metering equipment and may be used to obtain monitoring and specific data on spatial position of different objects of natural and artificial origin, and also on deviations of their surfaces from linearity. Device for measurement of instability of spatial position of lenses and detection of their shape deviation from linearity comprises laser, optical shaper of laser beam that creates referent direction, optical element that reflects and receives laser radiation, coordinate-sensitive receiver and unit of information processing; optical element that reflects and receives laser radiation is cassette with plastic film located in it along diagonal of thickness from 0.05 to 0.125 mm, required even tension of which is realised with the help of rollers with collet clamp, besides one end of film is fixed on one of rollers rigidly, and the other one - movably by axial rotation with the possibility of rigid fixation.

EFFECT: simplified design of device and improved accuracy of measurements.

2 dwg

Description

The invention relates to measuring technique and can be used to obtain monitoring and specific data on the spatial position of various objects of natural and artificial origin, as well as deviations of their surfaces from straightness.

A device for controlling deviations of the positions of objects from the laser beam, creating a given reference direction on the track, and a photoelectric sensor mounted on the object at the measured points [1].

The disadvantage of this device is the inability to simultaneously measure the spatial position of several objects, because during measurements, the reference laser beam is blocked by a photoelectric sensor.

The closest in technical essence and the achieved result is a photoelectric device for non-contact measurement of objects, containing: a laser, an optical laser beam former, for example, in the form of a telescopic system, a photoelectric sensor and plane-parallel glass plates located at an angle of 45 ° to the reference laser beam at certain distances between themselves and fixed together with the photoelectric sensor on the measured objects [2].

A disadvantage of the known device is that when the reference laser beam passes through plane-parallel glass plates on each of them there are two reflections from the air - glass - air interface, with a reflection coefficient of 6% at each interface (Fresnel reflection), which causes a double laser reference in the same plane on the photoelectric sensor, which may lead to additional errors or complicate the design of the photoelectric sensor in order to highlight one of the two reference laser beam directions.

To improve the quality of planes, plane-parallel glass plates must be selected from plates of large thickness, which is not less than 0.1 of the maximum size of plane-parallel glass plates, which leads to an increase in the cost and complexity of the design, since plates increase the total weight of the device and complicate its design. In this regard, the use of the device in the field is irrational.

The aim of the invention is to simplify the design of the device and improve the accuracy of measurements.

This goal is achieved by the fact that instead of a reflective optical element in the form of a plane-parallel glass plate, the device uses a plastic film, the thickness of which can vary from 0.05 mm to 0.125 mm, the tension of which is carried out using two cylindrical rollers equipped with collet clamps.

The first of these limits is determined based on the required minimum thickness of a commercially available film with the required strength.

The second - on the basis of the allowable magnitude of the ghosting of the reference laser beam. The invention is illustrated in the drawing, which shows a schematic diagram of a laser device for measuring the instability of the spatial position of objects and determine their shape from straightness. Figure 1 shows a side view, figure 2 is a top view.

The drawing shows a schematic diagram of a device containing a laser 1, an optical laser beam former 2, a plastic film 3 with a thickness of 0.05 mm to 0.125 mm, cylindrical rollers 4, a coordinate-sensitive receiver 5 (made, for example, in the form of a photodiode array and processing information processing units 6). The rollers 4 are installed in collet clamps 7, consisting of separate bushings and adjustable clamps. At the exit, after a translucent plastic film 3, the laser reference beam 8 and the reference direction 9 are shown. The plastic film 3 and the rollers 4 are combined into a cassette 10.

The device operates as follows. The laser 1 and the optical laser beam former 2 form the laser reference beam 8 and the reference direction 9. After the optical laser beam former 2, a cartridge 10 is installed with a plastic film 3 rigidly fixed to the rollers 4, for example by gluing, and located diagonally in the cartridge 10, creating a working surface for transmission and reflection of the reference laser beam 8. By scrolling one of the rollers 4 create a uniform tension of the film 3, which is fixed using collet mechanisms 7, while the dyne of the rollers 4 is pre-fixed with the same collet mechanisms 7.

After turning on the laser 1, the reference laser beam 8 passes through the working section of the film 3 and, simultaneously reflecting from it, enters a coordinate-sensitive photodetector 5 connected to the measuring information processing unit 6.

Information sources

1. USSR copyright certificate No. 785644, M.Kl. G01B 11/02, 07/26/1978

2. Copyright certificate of the USSR No. 781567, M.Kl. G01C 1/00, 12/18/1987 (prototype).

Claims (1)

A device for measuring the instability of the spatial position of objects and determining deviations of their shape from straightness, containing a laser, an optical laser beam former that creates a reference direction, reflects and receives laser radiation, an optical element, a coordinate-sensitive receiver and an information processing unit, characterized in that as laser element reflecting and receiving laser radiation, a cassette with a plastic film located diagonally in it is used thickness from 0.05 to 0.125 mm, the necessary uniform tension of which is carried out using rollers with collet clamps, while one end of the film is rigidly fixed to one of the rollers, and the other is movable axially rotated with the possibility of rigid fixation.

Images