Behaviour of light emission in a semiconductor gas discharge IR image converter

Light emission in the UV and visible (blue) range (330-440 nm) generated by an IR image converter and the possibility of locally increasing the gas discharge light emission for a given photosensitivity of a planar GaAs semiconductor photocathode were studied. The use of metallic patched concentrators with an area of S = 5x10-4 cm2 and a density of 400 cm-2 and an IR light to excite the photocathode of the system leads to a fivefold increase in the gas discharge light intensity. In a system with metallic patched concentrators, the local density of gas-discharge light exceeds the density of uniform gas-discharge light in an IR image converter by the same factor by which the working area of the photocathode exceeds the total area of the current concentrators. Moreover, the use of metallic patched concentrators prolongs the working time of the photocathode. The filamentation was primarily due to the formation of a space charge of positive ions in the discharge gap, which changed the discharge from the Townsend to the glow type