Patent ID: 8040440

Claim:
A projection device comprising: a light source which emits white light by alternating-current discharge; a color wheel which is inserted into an optical path of the light source and in which a plurality of color segments are formed at arbitrary sector angles along a peripheral direction of the color wheel, the color segments being configured to transmit a plurality of wavelength band components in the white light in a time division manner by rotating the color wheel; a color wheel driving unit which rotates the color wheel at a constant speed; and a light source driving unit which alternating-current discharges the light source at a period shorter than a rotation period of the color wheel while reversing a polarity at a timing to switch the segment of the color wheel inserted into the optical path; wherein a period of operation of the light source driving unit includes one of a first period where two color segments of the plurality of color segments constituting the color wheel are inserted into the optical path and a second period where three color segments thereof are inserted into the optical path, during one period of the alternating-current discharge of the light source.