Abstract: A shaft state sensor includes a rotating member having a miniaturized lamp mounted thereto. A rotary transformer is connected to the lamp and supplies it with power. A number of optic fibers are arranged in a circular configuration on a stationary member of the sensor. The center of the circular configuration is coaxial with the shaft of the rotating member. As the shaft turns, the lamp becomes sequentially aligned with each of the fibers thereby indicating changes in shaft position. The fibers are connected to an optical coupler which is in turn connected to an optical density discriminator for detecting when the light passing through a particular optic fiber exceeds the required threshold level. The output from the discriminator is optical and may travel over substantial cable distances to a computer location without the introduction of electrical noise so that shaft position or velocity may be computed.

Abstract: Ink jet printers include orifices which may become clogged or otherwise inoperative. This can cause printing defects which may go undetected for a substantial period because these printers usually operate unattended. An optical detector is provided for testing the operability of each ink jet orifice prior to the beginning of printing either a print cycle or a page. Ink is deposited on a member which moves the deposit through an optical path for detection. Absence of a deposit signals a malfunction.

Abstract: Methods are shown for deducing the point of impingement of a beam, such as particle or electromagnetic beam, on a planar detector which is much larger than the beam cross-section. The methods involve chopping the beam before it reaches the detector by means of a chopper which periodically obscures the field of view of the detector as a known function of the chopper motion, and then determining the point of impingement from output measurements of the detector and from the known geometry of the chopper and the detector.

Abstract: The invention relates to an ammonium phosphotellurate pyroelectric vidicon and detector.The pyroelectric detector comprises a dielectric material inserted between two parallel electrodes, said material being a monodomain ferroelectric monocrystal having a polaraaxis, wherein the said material is ammonium phosphotellurate of chemical formula:Te(OH.sub.6), 2[NH.sub.4 H.sub.2 PO.sub.4 ], [(NH.sub.4).sub.2 HPO.sub.4 ].