GB829841A - Improvements in compensating apparatus for interferometers - Google Patents

Abstract

829,841. Interferometers. ZEISS JENA C. VEB. Oct. 7, 1957, No. 31361/57. Class 97(1) A compensating device for interferometers comprises an optical path-length compensator consisting of relatively adjustable glass plates and a dispersion compensator also of glass plates, the latter being immersed in a liquid of the same refractive index and being adjustable independently or jointly, at least one plate being connected to the optical path-length compensator. The dispersion compensator shown comprises glass plates 6, 9 mounted in holders 5, 8 which are carried by trunnions 4, 7 rotatable about a common axis X-X in a receptacle containing liquid of the same refractive index as the plates. Freely rotatable on trunnion 4 is an arm 10 coupled to the holder 8 by the threaded end 11 of a spindle 12 passing through an arcuate aperture in holder 5. By means of a handle 14, spindle 12 can be moved to clamp holders 5, 8 so that they can rotate together about X-X. or to free the holders so that they can be relatively rotated about this axis. Rotation of holder 5 can be prevented by a clamping screw 20 while holder 8 can be rotated by arms 15, 16 connected to the path-length compensator (not shown). Screw 18 may prevent rotation of holder 8. Holder 15 carries a plate 25 bearing an index movable over a scale on a part 22 and screw 26 may be used to clamp the holder 5 to the part 22.