GB1180185A - Laser Beam Devices - Google Patents

Abstract

1,180,185. Lasers. TECHNIDYNE Inc. 1 April, 1968 [20 April, 1967], No. 15514/68. Heading H1C. [Also in Division G2] An optical sighting device or straight edge comprises a tubular gas laser arranged to emit aligned, collimated and focused light at both ends. As shown in Fig. 1, the gas laser 10 comprises a gas discharge tube 12 with Brewster angle windows 20, which is coaxially mounted in a cylindrical housing 14 by elastomer shockabsorbing rings 16. The optical resonator is formed by partially-transmitting mirrors 24, and each output path includes a transversely adjustable collimating lens 28 and a longitudinally adjustable objective lens 30. A laser straight edge is shown in Fig. 3 in which the gas laser 10, Fig. 1, is supported by elastomer ring mounts 44 in an outer easing 46 closed at its ends by optical windows 48. Sighting telescopes 52, 54 for the two directions of emission are detachably mounted on the casing 46. In a further embodi. ment, Fig. 4, parallel laser reference beams 74, 76 are provided by gas laser 10 which is vertically mounted within an inner tube 68 by elastomer rings 70, 72. The inner tube, in turn, is mounted within an outer tube 78 by integral support rings, the lower support ring 82 engaging a sliding ring 82A to permit relative movement. Parallelism of the emitted laser beams 74, 76 is effected by pentaprisms 96, 98 which are clamped to support plates 114. Alignment of the beams into the same direction is carried out by rotating movable end caps 88, 90 to which the plates 114 are respectively secured. The ends of the outer tube are terminated by housings 84, 86 having windows 100, 102 for the laser beams. Further windows 128, 130 are provided for optical paths 126, 128 extending from a sighting telescope 134 through a prism 136 and a pentaprism and beamsplitter (118, 120), Fig. 5 (not shown), the sighting telescope being used for alignment adjustment by observing laser beam reflections from a distant target. A beam splitter (170) may be added to pentaprism 96, Fig. 9 (not shown), to provide a laser beam in the direction opposite to beam 74. In use, the assembly is vertically mounted on a tripod by a gimbal mount, Figs. 7 and 8 (not shown), with the base in engagement with a screw adjustment.