Patent ID: 7004590

Claim:
An optical device manufacturing method for manufacturing an optical device having: a plurality of optical modulators that respectively modulate a plurality of color lights in accordance with image information; and a color combining optical system including a plurality of light-incident surfaces to which the respective optical modulators are attached and a light-irradiation surface from which the color light incident on the respective light-incident surfaces is irradiated after being combined, the method comprising: an optical properties acquiring step in which optical properties of a projection optical system to be combined with the optical device are acquired; a reference position acquiring step in which a reference position of the optical modulator relative to the color combining optical system is acquired; a deviation calculating step in which a deviation of the optical modulator relative to the reference position is calculated based on the acquired optical properties of the projection optical system; a combined light detecting step in which a combined light irradiated from the light-irradiation surface is detected using a light-beam detector; and an optical modulator position-adjusting step in which the position of the optical modulator is adjusted based on the deviation while detecting the combined light in the combined light detecting step.