1. Technical Field
The present invention relates to an optical device.
2. Related Art
An optical device such as eye glasses that can change transmittance by applying a voltage to liquid crystal or the like is known (see Patent Literature 1, for example).
[Patent Literature 1] Japanese Patent Application Publication No. S48-98846
Here, in some cases, an optical device is controlled by cyclically changing a voltage to be applied to liquid crystal or the like. However, flicker occurs if the cycle of the voltage and the blinking cycle of external light such as a signal are similar to each other.