SU699323A1 - Illumination system of phototaransformer - Google Patents

Description

The invention relates to photogrammetry, namely to devices intended for use in phototransformers for photo printing.

Lighting systems consisting of a mercury lamp with a reflector and a condenser are known. The condenser contains a set of LENS Fresnel 1.

A market for lighting systems using a condenser made of a LENS. Fresnel is the difficulty of making LENSES of large diameters, as well as the impossibility of sending them for printing transformable images with large angles of inclination and a wider range of magnifications.

Lighting systems are known, including a set of tubular xenon lamps with reflectors located throughout the FILE illuminator 2.

The disadvantages of these lighting systems are the difficulty of obtaining a sufficiently high luminance uniformity of the light outlet of the illuminator without significant loss of light in the diffusing glass, as well as the use of high power sources of high power light.

which leads to the complication of the cooling system.

A lighting system is also known, including four xenon lamps arranged in a rectangular shape and a reflector with a grooved surface. To protect the negative (up to 30 x 40 cm in size) from heating, a heat filter is used, located in the outlet of the illuminator, and the lighting device itself is air-cooled. The lighting device has the option of replacing lamps with halogen ones. The power of the lighting device - 8 kW 3.

Claims (4)

However, using a lighting system of this type in phototransformers, in which, along with projecting the entire picture, the image is transformed through a slit screen, it is not efficient, because at the time of slit transformation only a narrow strip of the negative is projected at the time, and the light flux , falling on the rest of the negative, is not used, the uniformity of the brightness of the lighting device is achieved by installing aa output of it with a hole in the diffusing glass, or a set of glasses with large scattering coefficients. This leads to a significant reduction in the negativeness of the negative, which is compensated by increasing the power of the light sources. The purpose of the invention is to more efficiently use the luminous flux and increase the uniformity of illumination of the negative during slit image transformation. This is achieved by the fact that in the illumination system of a phototransformer containing a reflector and a set of lamps between the outlet of the illumination system and the negative there are diffuse reflectors, on the side of the reflector, movable shutters forming a slit opening, with the possibility of simultaneous movement of two spring-loaded drums along the screen propeller-driven screw with gearbox. The inner surface of the reflector, made diffusely reflective, and the curtains form a cavity in which a multiple reflection of light occurs. Blocking the outlet of the lighting system to the desired size, receive an increase in brightness across the field of the slit opening. When transforming a snapshot into zones or entirely, the slides are diluted and open the outlet of the lighting theme to the required dimensions. The ria of FIG. 1 shows schematically the proposed lighting system; in fig. 2 is a phototransformer circuit in which a master system is used; in fig. 3 - diagrams explaining the course of the rays in the lighting system. The lighting system contains the reflector 1 with the internal lamines 2. The outlet of the illuminating system corresponds to the maximum size of the negative and has the shape of a rectangle. Internal surface. the reflector is diffusely reflecting according to a law close to the Lambert law. A similar coating from the side facing the reflector is provided by the shutters 3, from which the full reflection of the light falling on the unused parts of the negative at the time of the slit path is formed. When moving (in the process of transformation), the shutters are wound - unwinds on the drums 4, which are spring-loaded. The shutters, with the established gap 6, are fixed by a special clamp 5, which is screwed over the screw 6. The drive is carried out from the engine 7 through the gearbox 8. Fig. 2 shows a diagram of a phototransformer, transforming the picture 9 by means of the moving slot 10 on the screen 11. The arrows show the accepted direction of movement of the shutters 3 and shch.leli 10 in the process of exposure. The synchronous movement of the light reflecting curtains in the lighting system and the slit on the screen allows, through the lens 12, to project all the parts of the snapshot onto the photo material 13 located on the phototransformer screen sequentially. FIG. 3a is a diagram of the passage of the rays in the lighting system, in which the exit opening is blocked by curtains 3. The light emitted by the primary sources 2, mixing and repeatedly reflecting from the wall of the reflector 1 and the curtains, falls into the gap formed by the curtains. In this case, a high luminance uniformity over the entire length of the slit is achieved. FIG. 3 b shows a diagram of the passage of the rays in the lighting system, in which the exit opening is open to the desired size (when performing transformation in zones, or the entire image), the curtains 3 are wound on drums 4. When this occurs, scanning the desired part of the negative (not shown). FIG. 36 shows the distribution of the light intensity at the reflector surface at three points A, B, C. In the absence of limitations in dimensions, the shutter lighting system can be made of two diffuse-reflecting plates moving along guide plates. The presence of movable shutters overlapping the exit opening of the lighting system makes it possible to concentrate the luminous flux into a narrow strip, which leads to an increase in luminance within the used area up to 307 ° while reducing the effective area of the outlet a hundredfold, and since increasing the illumination of the negative leads to a decrease in exposure time, This also reduces the exposure time of the entire image, which in turn leads to an increase in labor productivity. Over the entire length of the slit, a high uniformity of brightness is ensured, which allows for obtaining good quality images. Claims The phototransformer illumination system containing a reflector and a set of lamps, characterized in that, in order to use the luminous flux more efficiently and to increase the uniformity of illumination of the negative during slit transformation of the picture, diffuse-reflective, from the illuminator side, mobile shutter curtain image