Viewing and direction finding device

摘要

Rows of LEDs (7,9) fit on an incoming window (6) i.e. a viewfinder window outside and on an outgoing window (8) i.e. a viewfinder window inside for a vision device (VD) (4) and are so positioned that the row of LEDs on the incoming window are visible to an observer on the top or bottom edge of the VD's field of vision (10).