DE1564949C - Image storage - Google Patents

Claims (1)

Claim: Image memory, using zinc sulfide or zinc-cadmium sulfide with manganese and halogen ions as an activator, which are embedded in a layer of ceramic material, which is arranged as the only layer simultaneously exhibiting photoconductive and electroluminescent properties between two electrodes, at least one of which is transparent and which are connected to a DC voltage source for storing the image, according to patent Ϊ 282'807, for 'the use of cathode rays as excitation radiation, characterized in that' the egg field, through which the cathode rays enter the image memory, at the negative pole of the DC voltage source. The invention relates to an image memory using zinc sulfide or zinc-cadmium sulfide with manganese and halogen ions as activators, which are embedded in a layer of ceramic material are the only ones that are photoconductive and electroluminescent at the same time Layer having properties is arranged between two electrodes, one of which at least one is transparent and which is connected to a DC voltage source for storing the image are connected, according to patent 1,282,807, for use with cathode rays as excitation radiation. The invention claimed in the main patent is based on the knowledge that one in a layer made of ceramic material embedded in a field strength suitable for a direct voltage electric field arranged, suitable phosphor emits light when it is an excitation radiation of a suitable wavelength or cathode rays. The phosphor emits hädh cessation of excitation • Light off for a long time, provided the coincident field is maintained. The invention is based on the object of using the image memory according to the main patent to make it much more sensitive with cathode rays as excitation radiation. This object is achieved according to the invention in that the electrode through which the cathode rays enter the image memory, is at the negative pole of the DC voltage source. If the electrode through which the cathode strings enter the image memory is connected to the negative pole of the DC voltage source, the image memory can be about 100 times more sensitive than when used with the opposite polarity. In this way, an image can be built up on the image memory even when using extremely low-intensity electrons, which is of particular value for certain purposes, such as e.g. B. in electron microscopy and image storage cathode ray tubes. Although the storage of the picture 'dätiei' is somewhat weaker than when the picture memory is connected to the DC voltage source in the conventional manner, this disadvantage is usually offset by the very considerable increase in sensitivity to cathode rays.
Another advantage of the image according to the invention ■ 30 memories, e.g. B. when projecting a television picture, It consists in the fact that the creation or the contrast of the image stored in the image memory is essential is larger than with conventional connection of the picture memory to the Gleichs'pä'rihüngsquelle. Therefore, more details can be seen in the stored image. This can be for special purposes be of importance, such as B. in the case of using an inventive image memory as a screen in an image intensifier or image converter.