| 摘要 |
774,051. Semi-conductor materials. STANDARD TELEPHONES & CABLES, Ltd. June 10, 1955 [July 6, 1954], No. 16814/55. Class 37. [Also in Group XL (a)] An electroluminescent radiation amplifier comprises a glass plate formed with V-shaped grooves 11 containing photo-conductive material 15 with metal strips 14, 14a running down the apices of the grooves and a series of elemental contacts 13 are formed on the base surface 12 between the grooves. Contiguous with the contact element 13 is a layer 16 of an electroluminescent material and superimposed thereon a plurality of terminal strips 18, 18a which are mutually insulated from each other. The layer 13 comprises a plurality of sets of insulated contact elements (Fig. 4, not shown), the contacts 14 and 14a are connected to the negative and positive poles respectively of a battery 21 and the contacts 18, 18a respectively across the alternating potential source 25. In order that the material 16 shall have a luminescing characteristic dependent on frequency and amplitude of the applied alternating voltage as well as on the D.C. bias, a stratum of polaristor material 29 is interposed between the luminescent material 16 and the contact element 13. This polaristor material may consist of colloidal suspensions of conductive particles in oil or alternatively of conductive or semi-conductive particles in a plastic layer which has been hardened in a strong polarizing electric field. Titanium dioxide is a suitable conductive material and the plastic may be either polystyrene, methyl methacrylate or urea formaldehyde. Alternatively the material 29 may be a ferro-electric material having the property of decreasing capacity with increasing bias. The effects of the polaristor and ferroelectric materials in improving the luminescent response and in giving either positive or negative reproduction are described by reference to Figs. 6 to 8 (not shown). In order that one portion of the photo-conductive layer 11 shall be unaffected by light the glass plate 1 is formed with a lenticular surface with the lens portions opposite that part of the photo-conductive material on which the light image is required to fall. Fig. 9 (not shown). Specification 766,416 is referred to. |
