Shigeo Tanji

Surface acoustic device having multistrip coupler comprised of alternate coupled and uncoupled strips

A surface acoustic wave device comprising a first set of interdigital electrodes that generate surface acoustic waves, a second set of interdigital electrodes that receive and convert surface acoustic waves into electrical signals, and an intermediate electromechanical coupling element provided therebetween. The coupling element comprises a plurality of parallel strips formed on the surface of a piezoelectric substrate such as to receive and change the direction of propagation of the surface acoustic waves, each of these parallel strips being spaced at a predetermined distance from each other and connected therebetween in a given manner to obtain suitable stopband characteristics.

Plastic lens array with the function of forming unit magnification erect image using roof prisms

An original plastic-lens array molded integrally as one block having a function of forming a unit-magnification erect image has been developed. The lens array consists of eight lens devices. The lens device has a roof prism, a reflecting v-groove, and a pair of convex-lens surfaces. A prototype of the lens arrays are arranged side by side. Thickness of the lens array is 4.5 mm, distance between object and image planes is 14.4 mm, array pitch is 1.3 mm, and the effective imaging region is 220 mm. The average modulation transfer function (MTF) at 41 p/mm of the lens array is 76% in the row direction (Y-direction) and 80% in the direction (X-direction) normal to Y-direction. The average F/NO in line-scanning is 1.8. The average irradience unevenness in line-scanning is 17%. The focal depth is +/- 0.6 mm in the area with the MTF being 60% or more. With this prototype a high-resolution image was attained. So, the lens arrays can be applied to imaging devices for use in a compact facsimile, image scanner, LED printer, and so on.

INTEGRATED MONOLITHIC CRYSTAL FILTER FOR CITIZEN BAND TRANSCEIVERS

This paper will describe a SSB 10.7 MHz IF filter for CB band transceivers employing an integrated capacitor circuit and four dual mode Monolithic Crystal Filters (MCFs) of AT cut Quartz. With a narrow bandwidth of 2 × 10−4, an insertion loss of less than 5 dB, and a low temperature coefficient of the center frequency of within ± 20 ppm over the range of − 35 to