GB191320771A - Improvements in and relating to Range Finders. - Google Patents

Abstract

20,771. Dyer, R. E. H. Sept. 15. Range finders; micrometer systems; prism systems.- In apparatus of the kind described in Specifications 18,616/11 and 19,201/12, a measure of the range is obtained from the movements of two object-glasses or two parts of an objectglass towards or away from one another in the same plane, and in a direction perpendicular to the plane of section. As shown in Fig. 1, the part object - glasses G, H are mounted in two tubes E, F, which are opened scissor fashion by pin-and-slot actuation from the mill-head J to obtain coincidence. In a modification, measuring- marks are moved relatively to scales in the eyepiece during adjustment. This movement may be magnified by suitable arrangement of levers &c. as indicated in Fig. 32, wherein j<1>, j<2> represent the part object-glasses and 48 the lever. In this Figure, the extension of the ray-path by the use of a roof-prism 47 as described in Specification 19,201/12 is shown, and also the use of two prisms as i or i<1> at each end of the base to replace one larger prism. In some instances, silvering of the prisms can be dispensed with, and in others, one eyepiece may receive rays direct from the object.