Laser image projector for siting shotholes - for blasting patterns in tunnels uses revolving optical system for laser beam projection

摘要

A laser image projector to produce a pattern for shotholes on the face of tunnels and other drivages includes a laser assembly (10) followed by a beam turning rotor (12), driven by an electric motor (11). This projects the laser beam (13) through a window (14) into a flanged beam deflector unit (29). The laser beam is directed by refraction in the prisms (16) into a predetermined direction so that the rays can be projected to the desired points at the tunnel face through the exit window (17) of a dust protection border (18). The disc (15), made of acrylic glass, holds the prisms (16) which have varying facets and which are pressed into it by deformation when they are hot.