Abstract: A fabrication technique for monolithic microwave integrated circuits employs silicon-on-sapphire wafers. Active and passive elements are formed together in a series of implant and deposition steps. Electrically isolated islands of semiconductor material are defined upon the substrate. Multiple metallization deposits are employed to simultaneously interconnect the individual circuit elements and form passive elements upon the integrated circuit. The technique allows mass production of integrated circuits with considerable raw material savings.

Abstract: The present invention relates to a novel automatic gray scale control circuit for a color television receiver. The circuit senses the cut-off voltage of each gun during the blanking interval, and uses a voltage equal to the cut-off voltage to energize the driver and bias the gun during the video field. The effect is to standardize the emission of each of the three guns against variation in gun cut-off voltage and to produce improved gray scale accuracy at the lowest emission levels. Since the gray scale adjustment is optimized at the lowest emission levels, where the eye is most intolerant to error in hue, one may avoid the need for manual adjustment of the cut-off point, and in cases where the gain does not vary widely from gun to gun, avoid the need for separate gain adjustment. Thus, the circuit may be used either to simplify or eliminate the color set up process at the factory when the receiver is manufactured. It may also reduce or avoid the need for readjustment after periods of use.