GB718651A - Improvements in or relating to optical goniometers - Google Patents

Abstract

718,651. Optical goniometers. IMPERIAL CHEMICAL INDUSTRIES, Ltd. Aug. 19, 1953 [June 23, 1952], No. 15737/52. Class 97(1) An optical goniometer head has a crystal mounting formed with a hemispherical supporting face received in a co-operating supporting socket whereby pivotal adjustment of the crystal mounting abut two axes at right angles can be effected by movement of the hemispherical supporting face with respect to the socket. As shown the instrument comprises a base 10 having an arm 12 in which a collimator 18 is adjustable by a ball socket joint 20, 23 and which supports a telescope 32 and a lens 24 which may be moved on to the axis 14 of the telescope to convert it to a microscope, focused by a knob 33 engaging a threaded portion of the support of the lens 24. The crystal 59 to be observed is supported in a mount having a hemispherical surface 50 engaging a corresponding surface in a tube rotatable about its axis in a support 49 mounted on a member 39 which can slide longitudinally on ball bearings on a plate 35 mounted on the base 10 for rotation about a vertical axis on ball bearings 34. The mounting, to which the crystal is held, for example, by a magnetic member is attached by a universal joint 57 to a rod 56, spring urged to hold the surface 50 against the tube 49 and attached to a base 53 carrying two arms 55 arranged at right angles and each engaged by a screw 58, adjustment of which rotates the base 53 and with. it the surface 50 about two axes at right angles. Alternatively the end of the rod 56 may be engaged directly by U-shaped plates 67, 68, Fig. 6, arranged as shown and sliding in perpendicular directions under the action of pinions 71 engaging racks in the plates, the rod 56 being held against the two plates by springs 69 attached thereto.