Patent attributes
There are provided a dimmer that can solve practical problems including burn-in and easily change a transmittance to external light and a video display device using the same. A dimmer includes a stack of two or more light control layers that change a transmittance to incident light by controlling an applied voltage in the incident direction of the incident light. A video display device includes a video generator that generates picture light; a video projector that projects the picture light as a virtual image in the field of view of a user; the dimmer disposed on the opposite side of the projecting side of the video projector to the user for adjusting the light quantity of external light to be entered to a user's eye through the video projector; and a light controller that controls the dimmer suitable for the luminosity of external light detected at an external light detector.