SU744778A1 - Device for photoexposure of screens of colour cathode-ray tubes with line structure - Google Patents

Description

The invention relates to the field of electronic engineering, in particular to the manufacture of CELT screens with slit masks.

A device for photoexposure of matrix screens is known .5

The light guide in the known device has such a design of the radiating head that, when using slit-type masks, it does not allow to obtain continuous luminous lines of the required width without translucent straps.

A device for photoexposing8 is also known (emitting CELT screens with a linear structure with slit masks, which includes a light source, a reflector and a wedge-shaped light guide with an output end G 23.

In the known device, a large side of a quartz fiber is made in the form of flat surfaces, and the output face has a rectangular shape. The use of such a quartz fiber to expose phosphor coatings

on CELT screens with slit masks, it is not possible to obtain continuous lumophore lines of a given width due to the presence of the necessary. Distribution of alert over the entire surface of the screen and in the light spot.

In addition, such a fiber design requires the use of complex methods of additional alignment of the illumination on the screen surface, due to the large ratio of the illumination in the central zone to the edges.

The purpose of the invention is to obtain continuous phosphor lines of a given width and to obtain a uniform irradiance distributor in the light spot.

This goal is achieved by the fact that in the device for photoexposure of CELT screens, the side surfaces of the fiber are made in the form of concave smoothly Coupled surfaces, and also the side surfaces of the fiber are the result of intersection, for example.

Claims (2)

a cylinder with two cones or a cylinder S1 / 1i, the axes of which are inclined at the same angle to the axis of the light guide and lie with more than one plane. In this case, the ratio of the transverse axis of the output end to its largest thickness lies within 1.5–3, with the portion of the end most large in thickness located at a distance of not less than 1/3 from the transverse axis, where t is the length of the fiber end. FIG. 1 shows a view of the proposed quartz fiber from the side of a concave surface; in fig. 2 light guide with. the side of converging faces; in fig. 3 - output end in excess of FIG. 4, curves of the distribution of lightness diagonally across the screen in relative units. The proposed light guide contains a spherical base 1, a cylindrical part 2, converging side faces (broad side) 3 with concave smoothly mated surfaces 4. Output T rec 5 enters the diaphragm 6 made in its shape, and the entire light guide is installed in a metal mandrel 7. The output end 5 of the fiber is a continuation of the concave smoothly mated surfaces 4 and consists of a central thin transverse part 8 and a thin part 9. The length of the radiating head 10 of the output end 5 depends on the design of the cusp, the overall dimensions of the screen, the distance from the mask to the surface of the screens, the width of the mask lintels: for a screen diagonally sized 25 cm-17 cm, for 61 CM screens - 28 cm. The ratio of the central thin part 8 of the transverse axis of the output end 5 to the greatest width 9 lies within 1.53, where part 9 of end 5 is greatest in thickness at a distance of at least 1/3 of its length 10 from the transverse axis. . The length of the thin part 8 of the end 5 is chosen taking into account the decrease in illumination in the central area of the screen horizontally (the luminous flux coming out of the 1/3 f end of the light illuminates the central area of the screen). The head of the output end 5 is rounded along the entire length and along the edge with a radius of 11 m and the lateral thin part 8 is filled with a radius of 12. The output end 5 is made in the form of a Fuzno-radiating head. The configuration and overall dimensions of the fiber, the ratio of the transverse axis of the output end to its greatest thickness, and the length of the thin part are determined taking into account the design features of the used photoexposure units and the required direction of the light rays in the optical fiber and their output from its output end, which further determines the distribution pattern illumination over the entire surface of the screen and in the light spot. The length of the fiber and the diameter of its part for different types of screens is constant. The proposed light guide is made of optical quartz glass. FIG. 4, curve 13 shows the illumination distribution (E) of the screen subdiagonalized when using a fiber with a rectangular face (known), and curve 14 with a fiber of the proposed design. Curve 14 shows that. The proposed fiber design significantly reduces the illumination in the central zone of the screen (more than S times) and increases it along the edges, which is very important with further alignment of the illumination across the entire screen field. The technological process of manufacturing screens line structure. the use of the developed device is typical. Using the proposed device for photoexposing CELT screens with slit masks makes it possible to manufacture three-color screens with continuous phosphor lines of the required width without distorting the strokes in the corners. Manufactured three-color screens with a ruled structure are distinguished by the high quality of solid phosphor lines of a given width and full filling. Claim 1. Device for photoexposure of color electron beam tubes with a lined structure, containing a light source, a reflector and a wedge-shaped light guide with an output end, so as to obtain continuous phosphor lines of a given width and to obtain a uniform distribution of illumination in 57 the light spot, the side surfaces of the light tube are made in the form of concave smoothly mating surfaces. 2. The device according to claim 1, so that the side surfaces of the fiber are formed by combining the cylinder with two cones whose axes are inclined at the same angle to the axis of the fiber and yes, lie about it in the same plane . 3. The device is in accordance with claim 1, so that the side surfaces of the fiber are intersected by two cylinders intersecting the cylinder, the axes of which are inclined at the same angle to the fiber bciet and lie in the same plane. 78 4. The device according to claim 1, about tl and h torn e e so that the ratio of the transverse axis of the output τ (fts to its greatest thickness lies in the range of 1.5-3, with the largest in thickness part of the end face located on not less than 1/3 of the Tonua length from the transverse axis of the light guide .. Sources of information taken into consideration during the examination 1. US patent number 3764366, class 117-33.5, published 1973. 2. US patent number 3840881,. cl. 354.1, published. 1974 (prototype). Phi tff.5 (at .e 40 to 1 & 160 160 bS 360 1 (Pgch) Thebes. fOO 4BG 560