| 摘要 |
<p>PCT No. PCT/AU96/00795 Sec. 371 Date Aug. 10, 1998 Sec. 102(e) Date Aug. 10, 1998 PCT Filed Dec. 6, 1996 PCT Pub. No. WO97/21261 PCT Pub. Date Jun. 12, 1997An apparatus and method for transmitting a hazardous electromagnetic beam (10). A hazardous beam (10) and a non-hazardous beam (12) are generated and directed along respective paths which are substantially parallel and either at least partially coincident or in close proximity so that an object will traverse the path of the non-hazardous beam (12) immediately before it is impinged by the hazardous beam (10). Any disturbance of the non-hazardous beam (12) by an object is detected and the hazardous beam (10) is disabled in response to a predetermined disturbance.</p> |
