Seiko Instruments Inc

Kabushiki Kaisha Daini Seikosha

Hirochika Sato

Takeshi Uchiyama

Yoshiro Sato

Yoshihisa Hagami

Haruo Nakayama

A single transmission line bidirectional optical communication system comprising a directional coupler employing a polarizing beam splitter, an optical transmitting circuit for coding the data and converting the coded data into optical signals and outputting said signals, an optical receiving circuit employing a comparator having a function of automatically establishing a threshold for converting optical input signals into electrical signals and then decoding the data, a circuit for detecting the frequency differences between the sending signals and receiving signals, and a line diagnosing circuit. The polarizing beam splitter eliminates a near-end reflected beam, and the optical receiving circuit having a function of automatically establishing a threshold eliminates a remote-end reflected beam. The line diagnosing circuit diagnoses the line condition by comparing the sending frequency and receiving frequency.

Single transmission line bidirectional optical communication system

A contour vibration mode piezoelectric resonator has a vibrating portion and at least one supporting portion integrally connected to the vibrating portion by way of a bridge portion. The supporting portion comprises a resilient portion directly connected to the vibrating portion, an attenuation portion integrally connected to the resilient portion and which is insubstantially displaced by vibration during use and a fixing portion fixable on a supporting member and which is either integrally connected to or forms a part of the attenuation portion.

Growing community of inventors

Tokyo, Japan

Hirochika Sato