Abstract: A multicolor or other multilevel infrared detector comprises at least one first detector element formed in a first portion of a lower body, e.g. of cadmium mercury telluride. At least one second detector element, having different detector characteristics, is formed in an upper body, e.g. of cadmium mercury telluride. The lower body is divided, preferably by ion etching into at least two (and more usually three or more) portions separated from each other by gaps. The gaps in the lower body are bridged by the upper body. Electrical connections to the second detector elements comprises the separate portions of the lower body. The electrical connections include metallization layers extending from the top to the substrate on which the lower body is mounted. The substrate may be of insulating material, e.g. sapphire, or it may be for example a silicon CCD for processing signals from the detector elements.

Abstract: A multicolor or other multilevel infrared detector comprises at least one first detector element formed in a first portion of a lower body, e.g. of cadmium mercury telluride. At least one second detector element, having different detector characteristics, is formed in an upper body, e.g. of cadmium mercury telluride. The lower body is divided, preferably by ion etching into at least two (and more usually three or more) portions separated from each other by gaps. The gaps in the lower body are bridged by the upper body. Electrical connections to the second detector elements comprises the separate portions of the lower body. The electrical connections include metallization layers extending from the top to the substrate on which the lower body is mounted. The substrate may be of insulating material, e.g. sapphire, or it may be for example a silicon CCD for processing signals from the detector elements.

Abstract: In a thermal-radiation imaging device a detector element comprises a semiconductor strip, e.g. of n-type cadmium mercury telluride, on which biasing-electrode means are spaced for causing a bias current predominantly of majority charge carriers to flow along each strip. The bias current supports an ambipolar drift of radiation-generated charge carriers in the opposite direction. A readout area is present in a part of the drift path between a pair of spaced electrodes. At least one space extends locally across the width of strip in-between the spaced readout electrodes from at least one side of the readout area to narrow at least locally the drift path in the readout area and to increase the electric field. A detector having increased responsivity results, particularly when at least two spaces extend from opposite sides to form a meandering drift path in the read-out area. Close spacing of the readout electrodes permits good image resolution even with a long meandering drift path.

Abstract: In a thermal-radiation imaging device a plurality of photoconductive detector elements are present on a common substrate. Each detector element comprises a semiconductor strip on which biasing-electrode means are spaced for causing a bias current predominantly of majority charge carriers to flow along each strip. The bias current supports an ambipolar drift of radiation-generated charge carriers in the opposite direction. Readout means for detecting these carriers comprises a connection protruding from one side of the strip. A recess extends across part of the width of the strip at the side opposite the readout connection. The readout connection of one strip extends into the recess of an adjacent strip so that a compact, closely-spaced and substantially aligned arrangement of the parallel detector elements can be obtained.