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A specially designed image intensifier tube for optical image processing has been developed. This tube can achieve the many types of processing important for pattern recognition such as deflection, zooming, gating, rotation, intensification, and logic operation in a single device. Experimental demonstrations are presented. Magnetic rotation of a pattern is proposed. The tube can perform the operations even in low level or incoherent light. Since processing is performed electrically or magnetically with no scanning, the processing speed is extremely fast.

In this paper a fiber laser plate, consisting of many fiber lasers in a form similar to an ordinary optical fiber plate, is described. The fiber laser plate, when end-pumped, can emit a laser light image corresponding to a 2-D transparency. The abrupt change of output intensity with excitation energy shows that the plate is attractive as an optical threshold device.

A laser light image corresponding to an image of an input transparency projected by a Rhodamine-6G dye laser has been emitted from an ultrathin GaAs crystal wafer. The image emission laser can be used as a new active device for optical parallel processings. Experimental results of image thresholding and wavelength converting are presented.

Some experiments were performed for the purpose of investigating the background noise source in channel electron multipliers, which had not been understood before. It was found that the noise pulses from one multiplier occurred sometimes in coincidence with the pulses from the other multiplier placed in the same vacuum chamber. As a result, it is believed that the noise source is not unavoidable, but the noise pulses will be produced by stray charged particles in the vacuum chamber entering into the multiplier. It is shown that a metal cap with a 30V bias voltage near the input end of the multiplier can reduce the noise efficiently, and no noise pulse was detected for more than one hour.

The dead time of a channel plate has been regarded so far as an inevitable defect in many applications; however, it is pointed out in this paper that it can be considered as the memory time during which the input image is stored. Line drawing, moving object detection, and inversion of images were performed by an experimental preprocessor using the dead time characteristics. The device should be recognized as a two‐dimensional operator with no scanning and without an electronic computer. The features of the device are very high‐speed operation and high sensitivity for dark images.

Several important problems in the fabrication of a channel multiplier plate were solved, and the characteristics of the improved plate were examined. Particularly, some characteristics necessary for application to image intensification, for example, gain uniformity and current transfer characteristics, were investigated. Since the discharge caused by high voltage had been prevented, a stable image was projected successfully on a phosphor screen. And also an experimental image tube using a channel plate was fabricated.

We originally propose and demonstrate optical parallel logic operations such as level slicing and the NOT and Exclusive OR (EXOR) operations using emission‐pulse time delay in a fiber laser plate and gating technique. These operations are essential for the optical digitial computations.

A fiber laser plate exhibits sharp transition and high contrast. We describe the first demonstration of all‐optical parallel logic operations such as A/D conversion and the AND and OR operations important for digital optical computers using the device as an optical switch array.

A practical high-speed image information preprocessor using a channel plate image intensifier, which can process optical images, has been developed. The preprocessor can perform logical operations such as summation, subtraction, or multiplication of two neighboring frame images on 16 mm film and can also detect moving objects by processing sequential frames. The operation time can be as short as 20 nsec. The image brightness can be as low as about 10-4 1m/m2.