| 摘要 |
The present invention relates to a new type of digitally controlled light chopper for acting on one or more independent channels of optical measurement or communication signals. This arrangement for acting on light comprises one or more chopper blade(s) mounted in a chopper housing with a fixed part and a movable part on spindles of step motors. The chopper blades have a number of holes which can either be completely open or provided with optical elements which act on light intensity or phase. The holes are positioned sequentially or non-sequentially by the digitally controlled motors between a number of openings arranged in pairs in the chopper housing when signal throughput (action on the signal) at a certain pair of holes is desired. The combination of pairs of holes is determined by the position of the fixed and movable parts of the chopper housing in relation to one another. The arrangement is used in order to open or act on the sensitivity of a common light detector to different light signals in optical measuring instruments or in order to open or act on a number of optical communication channels in fibre-optical data networks. <IMAGE> |
