| 摘要 |
1,254,206. Light modulation. COMMISSARIAT A L'ENERGIE ATOMIQUE. 20 Feb., 1969 [1 March, 1968], No. 9148/69. Heading H4F. An electro-optical cell for the phase displace. ment of a polarized light beam particularly for use in a fast light shutter for triggering a pulsed laser beam comprises two flat outer electrodes 44, 46 inserted in the outer conductor of a coaxial cable and a flat central electrode 124 inserted in the central conductor of the cable, and two crystals 120, 122 which exhibit the Loches effect, e.g. potassium dihydrogen phosphate or potassium nitrate, are diposed between the electrodes with their principal crystallographic axes at right angles to the electrodes and are rotated at 90 degrees to each other so that the successive phase displacements of the polarized beam passing therethrough are additive. The cell may be completely impedance matched with the coaxial cable, which can form part of a D.C. circuit or terminate in a short circuit, so that a voltage step giving a phase displacement of 180 degrees and having a rise time of e.g. 0À5 nsec. may be applied without any resultant deformation. The flat electrodes are provided with apertures 130, 132, 134 for the light beam, and layers of copper and flexible indium plates 125 are inserted between the crystals and electrodes except at the apertures. Placed between crossed polarizers, the cell acts as a light shutter. |
