PURPOSE: To improve the visibility of a liquid crystal display part even if the solar light is front or rear, by opening light-transmittably the rear side of the display part and conducting the solar light to the rear side.

CONSTITUTION: A liquid crystal cell body 12 of a liquid crystal display part 11 wherein a liquid crystal is sandwiched between glass or plastic plates is supported with a liquid crystal cell support part 13. A semitransparent reflection plate 12a is provided on the rear of the body 12, and the front and rear sides are protected with light transmittable protective plates 14 consisting of glass or plastic plates. The rear side of the display part 11 is light-transmittably opened and the liquid crystal display part is mounted to a frame body 15. If the solar light is the front light S2 that irradiates the vehicle from behind the same, segments 26 are dark by absorbing the light reflected by the plate 12a and a margin part 27 is bright by reflecting the solar light, thus making the display distinctly visible. In the case of rear light S1, the segments 26 are silhouetted and are dark by absorbing the light on the front side and the part 27 is brightly visible by allowing the transmission of the solar light.