Optical path shifting device, image display device, and method for controlling optical path shifting device

A method for controlling an optical path shifting device comprising an optical member having a shape of a rectangular plate and on which incident light is incident;

• a holding frame configured to hold the optical member;
• a support part configured to support the holding frame in a swingable state;
• an actuator configured to cause the holding frame to swing;
• a magnetic sensor configured to detect a position of the holding frame;
• and a temperature detection unit configured to detect a temperature of the magnetic sensor, the method comprising:
• inputting a reference signal to an amplifier and supplying a drive signal outputted from the amplifier, to the actuator;
• correcting an amplitude value of the holding frame found from an output from the magnetic sensor, using an output from the temperature detection unit;
• and
• adjusting an amplifier gain used to generate the drive signal, based on a difference between a corrected value of the amplitude value and a reference amplitude value.

An optical path shifting device comprising:

• an optical member having a shape of a rectangular plate and on which incident light is incident;
• a holding frame configured to hold the optical member;
• a support part configured to support the holding frame in a swingable state;
• an actuator configured to cause the holding frame to swing;
• a magnetic sensor configured to detect a position of the holding frame;
• an amplifier configured to supply a drive signal to the actuator;
• and
• a signal processing unit configured to supply a reference signal to the amplifier, wherein
• the optical path shifting device is arranged in an optical path of image light,
• the actuator is driven to change the optical path of the image light, and
• the signal processing unit has a gain adjustment unit configured to adjust an amplifier gain used to generate the drive signal, based on an output from the magnetic sensor.