GB626621A - Improvements relating to microscopes - Google Patents

Abstract

626,621. Microscopes. CENTRE NATIONAL. DE LA RECHERCHE SCIENTIFIQUE. Aug. 30, 1945, No. 22378. Convention date, Sept. 1, 1944. [Class 97 (i)] A microscope is characterised in that an image of a polarising device, e.g. a polarising biplate disposed in the light path between the light source and the condenser of the microscope is formed by the condenser in the object plane of the microscope. As shown in Fig. 2, light from a source 9 is polarised at 1 and reflected at 8 so that the polariser 1 is imaged by the condenser 2 in the plane of the specimen 5, and observations are made through the objective 6 and eye-piece 7 of the microscope. The polariser 1 may consist of juxtaposed pieces a, b, Fig. 4, of dichroic film with their principal sections X, Y orthogonal. By rotation of the polariser 1, which is also movable in two orthogonal directions so that the image of the dividing line c of pieces a, b may intersect the specimen, the dichroic property thereof may be determined. Alternatively, the specimen may be rotated or a mica half-wave plate disposed at 11 may be rotated for the same purpose; the biplate 1 may also be replaced by a Nicol prism 13 and a half-wave plate 12. In order to determine the birefringence of the specimen 5, an analysing eyepiece may be used, a half-wave plate being disposed between the objective 6 and the specimen and coupled with the half-wave plate 11 so that they may rotate in unison. Using a Soleil biplate the rotation power of the specimen may be determined. Observations may also be made of the circular dichoism of the specimen using a double quarter-wave plate and an ordinary polariser. To avoid elliptically polarising the light by reflection at 8, two relatively inclined mirrors may be used or the light-source may be disposed along the microscope axis. The Specification as open to inspection under Sect. 9] states that the polarising device may be replaced by a grid, an index, a photograph, a spectrum or other comparison object. This subject-matter does not appear in the -Specification as accepted.