<p>Apparatus and methods for detecting angle of incidence of an optical beam. The apparatus employs two optical detectors, the first of which has placed in front of it a coating or layer which exhibits an angle-dependent optical transmission characteristic distinct from that of the light path in front of the second detector. The difference in a characteristic of the light received at the respective detectors therefore provides an indication of the angle of incidence of the light beam. The angle detector may be used particularly, though not exclusively, in conjunction with free space optical communications systems.</p>
申请公布号
EP1946168(A2)
申请公布日期
2008.07.23
申请号
EP20060794823
申请日期
2006.10.19
申请人
QINETIQ LIMITED
发明人
SCOTT, ANDREW, MAXWELL;LEWIN, ANDREW, CHARLES;RIDLEY, KEVIN, DENNIS