Microcapillary plate as a built-in intensifier for semiconductor gas discharge image converters

Abstract

Using a microcapillary discharge plate (MCDP) integrated with the discharge gap of a semiconductor gas discharge infrared image converter has been tested as a basis for building gas discharge image converters with internal image intensification. A Townsend-type discharge with current density controlled by infrared illumination of the semiconductor cathode is produced in a 100 μm gap in Ar gas under pressures of 50 – 200 hPa. Electrons generated in the discharge gap are multiplied by a non-self-sustained discharge in the MCDP of 100 μm thickness, which has just a single channel 200 μm in diameter. The authors have observed a significant increase of the discharge brightness in the MCDP channel compared to that of the main discharge gap.

Study of light emission amplification in a semiconductor gas discharge system

“…We also believe that on the basis of the outlined principles, by using dielectric spacer of proper design with a large number of microcapillary channels and a single-hole microcapillary discharge plate (i.e. suggested in [14]) it is possible to build ultrafast and rather sensitive SGD IR converters with internal image amplification, which are controlled by the IR light.…”

“…Due to the interaction with solid surfaces, the rate of quenching the excitations of light-emitting species can be essentially increased, as compared with the volume values. As a result, speed properties of these discharges considered as light-emitting media can be substantially increased, when compared with those observed for volume gas discharge plasmas [14]. The maximum emittance of GDLE, which depends on the basic characteristics of an ionization system for given values of the residual pressure, the feeding voltage and the intensity of external illumination, is determined by the photosensitivity of the semiconductor cathode.…”

“…Since the current is concentrated in the microcapillary channels, the source of the loss of resolution i.e. electron scattering with the flight between the discharge electrodes disappears [14]. Thus, the device with microcapillary MCS shows good technical performance (i.e.…”

“…To produce ionization in the microcapillary channels of the MCS, a regular process of collection and amplification takes place; electrons released can drift into the microcapillary channels and multiplied depending on potentials. The operation of the SGD system with MCS is, in principle, similar to that of gas electron multipliers [13], microcapillary discharge plate [14] and capillary plates [15] used in position-sensitive gas proportional counters, microstrip gas chambers and 'gaseous photomultipliers' [16].…”