Abstract: An erasable electro-optic storage disk for use in focused laser beam operated data handling systems comprises a semiconductor substrate with a storage layer arranged on top of it that is capable of trapping charge carriers. Electric contacts are connected to the semiconductor substrate and to the storage layer, respectively. An energy barrier with associated depletion zone is formed in the substrate near the interface with the storage layer. Upon simultaneous application of a control voltage to the contacts and of a focused laser beam directed at a storage site, electron pairs are generated in the depletion zone, and charge carriers are transferred towards the interface. This causes a reduction of the depletion zone and thus of the voltage over the depletion zone, and an increase of the field in the storage layer, whereby charge carriers are injected into and trapped in the storage layer; method of recording, reading data and apparatus therefor.

Abstract: Sense amplifier for use in memory systems, particularly static random access memories (RAM). The sense amplifier circuitry comprises two inverters, one forming a regular amplifier, the other providing a reference voltage (V.sub.Ref) to the amplifier for determining the optimal operating point (A.sub.o) on the inverter's transfer curve, and to a bit line associated with a memory cell being read for biasing the line at its optimal operating level.The inverters used in the sense amplifier as voltage reference and as amplifier as well as the inverter pairs forming the memory cells may have similar structure and properties and can be formed on the same semiconductor chip.