Patent Number: 6,295,151

Title: Optical transmission and receiving equipment

Abstract: An optical transmission and receiving equipment to comprises an opticalsource emitting a laser beam; a optical receiving instrument for receivingthat laser beam; an optical filter established between that optical sourceand optical receiving instrument; a rotary mechanism to change the tiltangle of the optical filter in relation to the laser beam; and a tiltangle controlling instrument for controlling the movement of the rotarymechanism. The tilt angle controlling instrument varies the tilt angle ofthe optical filter within a prescribed period. Therefore, in theaforementioned optical transmission and receiving equipment P, thetransmittance of the laser beam L1 passing through the interference filter2 is automatically controlled to become the maximum by the control signalbased on the received light intensity signal S0 of the optical receivinginstrument 3. Consequently, the equipment can use a narrowband bandpassinterference filter, which effectively removes background optical noise,without using a special instrument for controlling the temperature of thesemiconductor laser.

Inventors: Nagai; Masaru (Tokyo, JP)


International Classification:

Expiration Date: 09/25/2013