Optical unit and electrolytic solution

摘要

To provide an optical unit which can be driven with low electrical power, is controllable in its transmittance in visible light, has satisfactory spectroscopic properties in a light-screening state, and exhibits a life span extended by reducing the over-voltage upon the electrodes; and to provide an electrolytic solution to be used in the optical unit. An optical unit comprising a pair of opposing electrodes 2 and 3, and an electrolytic solution 1 comprising a solvent and a silver bromide dissolved therein, the electrolytic solution further containing a metal salt such as copper bromide to be co-deposited with silver, and the electrolytic solution being disposed between the opposing electrodes such that deposition/dissolution of silver is caused by drive-controlling these electrodes. <IMAGE>