Patent ID: 7128477

Claim:
An optical transmitter and receiver module connected to an optical fiber, which transmits a first light and receives a second light via said optical fiber, said module comprising: a light source emitting said first light; a light-receiving section receiving said second light; a diffraction device through which both the first light and the second light are transmitted, the diffraction device changing the direction of travel of at least one of said first light and said second light so that an optical axis of said first light and an optical axis of said second light are separated; a first lens which condenses said first light, outgoing from said light source and entering through the medium of said diffraction device, onto a light input/output face of said optical fiber and condenses said second light outgoing from said optical fiber onto said light-receiving section through the medium of said diffraction device; and a second lens which inhibits a beam of said first light outgoing from said light source from diverging and allows it to enter said first lens through the medium of said diffraction device, wherein said second light is received by said light-receiving section without transmitting said second lens.