Abstract: A driving circuit arrangement for a gas-discharge display device consisting of an array of discharge lamps applies to the array a discharge retaining voltage composed of a voltage less than is required to maintain a discharge and a voltage equal to the magnitude of a `half-pulse,` the use of two coincident half-pulses being sufficient in addition to the retaining voltage to strike a discharge. To extinguish a discharge in one or more of the lamps the voltage equal to a half-pulse is removed temporarily from one of the conductors associated with the lamp, thereby reducing the voltage across all the lamps connected to that conductor below the level required to retain a discharge, and a compensating voltage of magnitude equal to a half-pulse is temporarily applied to the other conductor of those lamps in which it is desired that the discharge not be extinguished.

Abstract: Semiconductor devices are mounted on corresponding lead frames by being inserted into apertures of a masking member in a desired registration with the lead frame strip.

Abstract: A detector of blemishes in a surface comprises a transmitting station from which a beam of light is caused to scan a moving surface to produce a raster pattern thereon. Light specularly reflected from, or transmitted by, the surface is collected at a receiving station after being diffused by a sheet of translucent material disposed in the path of this light. The diffused light in the receiving station is collected and directed by reflective surfaces towards a photodetector such that when the beam engages a blemish in the surface, the amount of light detected falls. The detector combines the sensitivity of collecting large amounts of specularly reflected light with a simple optical system associated with the collecting of diffused light.