Abstract: In a vacuum tube oscillscope for storing and reproducing electric signals, two matrices of charge transfer devices (CTDs) register and then reproduce the electric signals on a display screen. The two CTDs (21, 22) are juxtaposed at their sensitive areas (23, 24) without any interruption in accordance with a boundary which is substantially perpendicular to the time base deflection. The CTDs are scanned in accordance with trace and retrace write scan sequences. This facilitates reproducing the electric signals with pre-triggering.

Abstract: A vitreous semiconductor supporting structure obtained by connecting semiconductor layers to a vitreous support constituted by at least two glasses. The semiconductor layers are constituted by an electrically and optically active n-ary III-V compound layer (3) and optional complementary layers for passivation (4), index adaptation (6), and protection (7). To keep the active layer in a compression state and optimize its electrical properties, the structure includes at least two glasses, an intermediate glass (15) providing thermoelastic properties and a supporting glass (16) providing a high softening temperature.

Abstract: The photocathode is of the type which comprises a photo-emissive layer consisting of at least an active layer of the P-type, a solid support for said semiconductor of a material which is transparent to radiation, a layer having a bonding glass for the photo-emissive layer on the support. The invention is characterized in that the support comprises two parts situated one on top of the other and which are bonded together, namely a thick second part (thickness for example 5 mm) of a type of glass having properties of thermal expansion which are substantially identical to those of the bonding glass and a part in the form of a disk-shaped first part (thickness for example 1 mm) of a material having softening and transition points which are much higher than those of the bonding glass and of the glass of the thick part.