Patent ID: 7356261
Filing Date: 2008-04-08
Classification: H04B

Abstract:
1. An optical wireless communications system comprising: a first optical wireless communications apparatus for transmitting a pilot beam to be used for optical-axis matching; and a second optical wireless communications apparatus having an optical transmitter for converting a video signal into an optical signal and transmitting the optical signal and an optical receiver with optical receiving areas for receiving the pilot beam the optical receiver being adjusted in directions of pan and tilt so that amounts of light of the pilot beam received at the optical receiving areas are equal to each other to have a match for an optical axis of the first optical wireless communications apparatus and another optical axis of the second optical wireless communications apparatus, wherein the first optical wireless communications apparatus includes an optical receiver for receiving the optical signal transmitted by the optical transmitter of the second optical wireless communications apparatus, a control-signal receiver for receiving an external remote control signal for controlling at least either the second optical wireless communications apparatus or an apparatus connected to the second optical wireless communications apparatus and a modulator for modulating the pilot beam with the external remote control signal, the pilot beam being different from the optical signal and used for optical-axis matching between the first and second optical wireless communications apparatuses, the first optical communications apparatus further includes an optical transmitter for transmitting the modulated pilot beam to the optical receiver of the second optical wireless communications apparatus, and the second optical wireless communications apparatus includes a demodulator for demodulating the modulated and transmitted pilot beam to reproduce the external remote control signal, whereby the first optical wireless communications apparatus and the second optical wireless communications apparatus perform optical communication using the optical signal along the optical axes that are matched based on the pilot signal.