SU1456985A1 - Sunlight protection device - Google Patents

Abstract

The invention allows to increase the image contrast on the light mosaic information boards in high ambient light conditions. This is achieved by the fact that the beams of the light indication element emerge through the gap between the opaque elements 1, which are in the form of angles, the outer surface of which is mirrored, one of which is facing the indicator and is arranged vertically. Light beams from external sources are attenuated by the shielding properties of the internal surfaces of opaque elements made light-absorbing. Opaque elements 1, made in the form of corners, are connected along the edges by vertical posts 4, forming a lattice. 2 Il. i (L SD SG) from 00 O

Description

The invention relates to information technology and can be used in mosaic information boards to protect display elements from illumination under high ambient light conditions and to increase image contrast.

The purpose of the invention is to increase the image contrast in high ambient light conditions.

Figure 1 shows the device, a general view; figure 2 - section aa on

figure 1.

 The light-shielding device contains opaque elements 1, made in the form of angles, the surface 2 of which is light-absorbing, and the surface 3 is a reflective and vertical posts A. The ratios of a / h and b / h, where a is the width, b is the height; opaque elements, and h is the distance between them, depending on the location of external light sources and the placement of stationary boards.

The device works as follows.

The light rays of the display element go out through the gap between elements 1 and extend in the range from the angle LC to the angle where c / is the maximum angle of the light flux from the indicator that can pass through the gap and is directed upwards the reflection of the light flux from the indicator and is directed downwards.

From the right triangle

Lvsh-b

M, arctg ---

ci

It follows from the similarity of dPNL and LJ, PNIfiCa-MK W

  -5G Mi; - h-b F -

  2h-b

From 21NLP, where L-Yr, we have

i

arctg -2h-b arctg ---,

for h 2b, the projection of the ray LP coincides with the point K, and the angle Lf will be formed by the normal to the side b and a -55 of mine to P.

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Part of the beams of the light indication element, falling on the vertical outer surfaces 3 of the angles 1, scatter a number of reflections inside the cavity formed by the exit hole of the light indication element and the thin side of the light-shielding device, the other part comes out through the gap. Some of the rays from an external source are absorbed by the inner surface 2 of the corners 1, painted, for example, with a light-absorbing paint, and a smaller part, having a dip angle less than i /, falls into the gap between these corners 1.

Thus, the increase in contrast, i.e. an increase in the ratio of the brightness of the light element of the display to the brightness of the background is achieved by the fact that the luminous flux of external sources is weakened by the shielding properties of the sides of the corners 1. .

The use of angle 1 significantly reduces the width of its horizontal side.

When using the invention in a scoreboard with high-voltage indicators, the end surface of which is close to the Lamberto surface, it is possible to exclude light filters and protective glasses while improving heat transfer and operating characteristics of display media.

Claims (1)

Invention Formula A light-shielding device containing opaque elements horizontally one above the other and connected along the edges by vertical posts, one surface of the opaque elements made light-absorbing, and the other reflective, characterized in that, in order to increase the contrast of the image under high external illumination, opaque the elements are made in the form of angles with light-absorbing internal and mirror external surfaces, one of which faces the indicator and is located vertically ikalno.