System and methods for position-control of light modulation device

A method for controlling the position of a light modulation device, which uses a position-control device that controls the position of the light modulation device, the position-control device being used in the manufacture of an optical unit having a plurality of the light modulation devices and a combining optical system that combines the light modulated by each light modulation device, the position-control device projecting the light combined by the combining optical system to form a projection image displayed on a screen via a projection optical system and detecting data of the projection image displayed on the screen by at least one detecting device, thereby controlling the positions of the light modulation devices, the method comprising:

• controlling an initial position of each light modulation device such that the light modulation device is moved so that the position of the optical center of the light modulation device coincides with a predetermined reference position;
• lighting a light source that generates light to be applied to the light modulation devices;
• controlling the position of the detecting device such that the detecting device is moved along the screen in accordance with the data of the projection image projected on the screen with the light being lighted in the step of lighting the light source;
• controlling a focus of the detecting device;
• and
• controlling the positions of the light modulation devices after controlling the focus of the detecting device in the focus controlling step.

A method for controlling the position of a light modulation device, which uses a position-control device that controls the position of the light modulation device, the position-control device being used in the manufacture of an optical unit having a plurality of the light modulation devices and a combining optical system that combines the light modulated by each light modulation device, the position-control device having a reference projection optical system which projects the light combined by the combining optical system to form a projection image and has a predetermined optical characteristic, the reference projection optical system being built in so as to be commonly used, and at least one detecting device that detects data of the projection image displayed on a screen via the reference projection optical system, the method comprising:

• controlling an initial position of each light modulation device such that the light modulation device is moved so that the position of the optical center of the light modulation device coincides with a predetermined reference position;
• automatically controlling the position of the detecting device such that the detecting device is automatically moved along the screen in accordance with the predetermined position of the optical axis of the reference projection optical system;
• lighting a light source that generates light to be applied to the light modulation devices;
• and
• controlling the positions of the light modulation devices after controlling the position of the detecting device in the step of automatically controlling the position of the detecting device.