Patent ID: 7116849

Claim:
An optical transducer for converting a physical quantity of objects to electric signals, comprising: a light emitter for outputting sensing light; a photo-electric converter for converting said sensing light to electric signals representative of said physical quantity; plural outgoing optical fibers connected to said light emitter, and propagating said sensing light toward said objects for radiating said sensing light to said objects; and plural returning optical fibers connected to said photo-electric converter, and propagating said sensing light modified with said objects to said photo-electric converter, wherein one of said light emitter and said photo-electric converter comprises plural transducers for producing one of said sensing light and said electric signals, and a holder maintaining said plural transducers inside thereof and including a plug portion formed with plural ports selectively receiving said plural outgoing optical fibers or said plural returning optical fibers in such a manner that said plural outgoing optical fibers or said plural returning optical fibers are secured to said plug portion by means of adhesive compound cured in a radiation of a curing light, in which said plug portion is made of synthetic resin having a transmission wavelength range substantially permitting said curing light to pass therethrough and a cutoff wavelength range different from said transmission wavelength range and substantially prohibiting said sensing light to pass therethrough.