SU468207A1 - Projection scanning device - Google Patents

Description

equal to 90 °, and the angles between the beam-splitting plane and the said axes are 45 each.

The lenses 4 and 7 are calculated so that their entrance pupils are located at the same distance from the plane of frame 1. On the continuation of the optical axis of the projection lens 7, behind the splitter 9, a flat mirror 10 is installed, optically conjugated to the screen plane using the splitter 9 and the additional component And, made in the form of a single positive lens, located in the immediate vicinity of the mirror 10 (which can be combined with the flat surface of the component 11). At the same time, the front focus of the component And, as well as the rear focus of the lens 8, is combined with the help of a splitter 9 with the center of the aperture diaphragm 12 of the reproduction lens 4. The scales of the image of the planes of frame 1 and the mirror 10 on the screen 2 are the same, i.e. sizes with the processed frame.

If a photodetector 13 is used in the device to provide semi-automatic and automatic operation, it is advisable to arrange it on the same side of frame 1 as the illuminator 3 (a semi-transparent mirror 14 can be used to direct radiation to the photodetector 13).

The device works as follows.

The light mark created by the shaper 5, using a projection lens 7, a beam splitter 9, lens 8 and component I, is simultaneously projected on the plane of frame 1 and the mirror 10. The mark on the frame 1 field is moved by turning the mirror 8. The reproduction lens 4 together with the lens 3 and component And projects on the screen 2 at the same time the image of the plane of frame 1 and the plane of the mirror 10 with a label. Since the scales of projection of the planes of frame 1 and mirror 10 onto screen 2 are equal, the position of the image of the mark on the screen is completely equivalent to its position on the frame. Therefore, the operator, observing the position of the image of the mark, knows the position of the mark on the frame, which allows him to combine the mark with any element of the processed tracks. Since in the proposed device the radiation forming the image of the light mark on screen 2 does not pass through frame 1, the brightness of this image does not depend on the density of the frame under study. This makes it possible to process frames of any density manually. When combining the light mark with the track on frame 1, the photon receiver 13 receives a useful signal, which is used to determine the coordinates of the tracks and to control the scanning elements in the automatic mode of operation. Due to the proposed layout of the main systems of the device, the photoreceiver 13 receives only the radiation from the light mark and the radiation from the illuminator 3 does not get, so the signal /

the noise in the proposed device is higher, and, consequently, the accuracy of determining the coordinates of the tracks is much higher than in the known.

Thus, the proposed device has a number of important advantages, providing a significant expansion of its operational capabilities.

Subject invention

A projection-scanning device containing a frame projection system on a screen with an illuminator and a reproduction lens located on opposite sides of the frame, a light mark projection system on a frame with a projection lens and scanning elements and a positive lens located near the frame plane on the side of the reproduction lens, the back focus of which combined with the aperture stop diaphragm of the reproduction lens, characterized in that, in order to expand the range of application and increase and the accuracy of measuring the coordinates of the frame elements, the illuminator and the projection system of the light mark are located on opposite sides of the frame, while the device is equipped with a beam splitter installed at the intersection of the optical axes of the reproduction and projection lenses and located

behind the beam splitter at the extension of the optical axis of the projection lens with a flat mirror optically conjugated with. the plane of the screen using a beam splitter and a positive component, the focus of which is combined with the center of the aperture diaphragm of the reproduction lens.