Patent ID: 6208445
Filing Date: 2001-03-27
Classification: H04B

Abstract:
An apparatus for wireless optical transmission of video and/or audio information with a signal source (1,4) which supplies at least one pulse-shaped source signal (Se) denoting the video and/or audio information through the temporal position of rising and falling signal edges (H/L, L/H) between pulses and non-pulse periods, wherein the source signal (Se) is converted by a signal processor (24, 34, 37, 38) which is specific to the type of the signal source (1, 4) into a playback signal (CV, L, R) for a video and/or audio playback unit (2, 3),with a source signal converter for converting the source signal (Se) into a channel pulse signal (Sk),with at least one luminescent diode (16) for radiating a signal radiation (Sl) which is at least modulated with the channel pulse signal (Sk), into the surrounding free space,and with at least one photo receiver (20, 30) comprising means (23, 24, 33, 34, 37, 38) for recovering the video and/or audio information contained in the received signal radiation (Sl), characterized inthat the source signal converter includes an edge detector (14) for generating a channel pulse signal (Sk) provided at each rising and falling signal edge (H/L, L/H) of the source signal (Se) with a channel pulse (Pk) which is several times shorter than the duration of the pulses and the non-pulse periods of the source signal (Se),and that the means for recovering the video and/or audio information comprises at least a 1:2 frequency divider (23, 33) in a photo receiver (20, 30) and the signal processor (24, 34, 37, 38) specific to the type of the signal source (1,4).