Patent attributes
An indicating instrument for a vehicle has a display board, a light modulation member disposed to cover a surface of the display board. An illumination intensity of the display board is detected by a light detecting member and a control unit applies to a dc pulse voltage to the light modulation member, to thereby control a light transmissivity of the light modulation member according to the illumination intensity. When the illumination intensity is higher than a predetermined level, the voltage is applied in one direction so that the light modulation member changes from a colorless condition to a colored condition to restrict an external light from reflecting on the display board. When the illumination intensity is lower than a predetermined level, the voltage is applied in a reverse direction so that the light modulation member is transferred from the colored condition to the colorless condition to maintain the visibility of the display board.
