| 摘要 |
830,930. Interferometers. PERKIN-ELMER CORPORATION. April 25, 1956 [April 28, 1955], No. 12633/56. Class 97(1) Apparatus for producing, in a single plane, traces corresponding to the distribution of refractive index and the refractive index gradient in a substance comprises means for passing a light beam through the substance and a second light beam through a standard substance, a phase-splitting device through which the beams then pass and which changes the phase of part of the two beams relative to that of the other part, and an astigmatic lens system imaging the phase-splitting device and the substance in the observation plane whereby a system of interference fringes is obtained giving the required information. As shown light from a source 10, is condensed by lens 11 on to a plurality of sheets 13 whence it passes via slit 15 and lens 16 to slits 20, 21 placed before a Tiselius cell having two compartments, one containing the substance under test and the other a standard substance. The emergent beams pass through the phase splitting device 22 divided by an oblique line 25 into areas 23, 24 differing in optical thickness by half a wave length of the light used. The beams are finally focused upon the surface 28 by spherical lens 26 and cylindrical lens 27. |
