Patent ID: 8335430

Claim:
An optical data transmission apparatus comprising a first communication unit and a second communication unit arranged to face each other in such a manner to be movable relatively to each other, the first communication unit including: a first optical signal transmission unit including a light emitting unit having a laser diode for emitting single-mode light, a multi-mode optical fiber for guiding a single-mode optical signal output from the light emitting unit, converting the single-mode optical signal into a multi-mode optical signal, and outputting the multi-mode optical signal, an optical lens for forming the optical signal output from the multi-mode optical fiber into parallel light, and a first polarization element for passing the optical signal polarized in a first direction out of optical signals output from the optical lens; and a first optical signal reception unit including a second polarization element for passing an optical signal polarized in a second direction that is different from the first direction out of incident optical signals, an optical lens for condensing the optical signal passing through the second polarization element, and a light receiving unit for receiving the optical signal output from the optical lens, and the second communication unit including: a second optical signal transmission unit including a light emitting unit having a laser diode for emitting single-mode light, a multi-mode optical fiber for guiding a single-mode optical signal output from the light emitting unit, converting the single-mode optical signal into a multi-mode optical signal, and outputting the multi-mode optical signal, an optical lens for forming the optical signal output from the multi-mode optical fiber into parallel light, and a second polarization element for passing the optical signal polarized in the second direction out of optical signals output form the optical lens; and a second optical signal reception unit including a first polarization element for passing an optical signal polarized in the first direction out of incident optical signals, an optical lens for condensing the optical signal passing through the first polarization element, and a light receiving unit for receiving the optical signal output from the optical lens.