Color wheel, and color wheel assembly incorporating same
There is provided a color wheel including a plurality of color filters arranged so as to form a disk, and a retainer member disposed at a center of the disk and formed into a C-ring defining an open mouth portion through which an area of one color filter is exposed. Also, there is provided a color wheel assembly which incorporates the color wheel described above, and which further includes a motor to rotate the color wheel, and a rotational position detector to optically detect a rotational position of the color wheel. Detection light emitted from the detector is set to fall incident on the C-ringed retainer member while the color wheel is rotated thus intermittently impinging on the open mouth portion, namely on the one color filter, which causes the detection light reflected thereby to come out with two different intensities that are sensed by the detector.
1. A color wheel assembly comprising:
a color wheel including a plurality of color filters arranged so as to form a disk configuration, and a retainer member disposed at a center of the disk configuration and formed into a C-ring defining an open mouth portion, the open mouth portion overlaping one of the plurality of color filters;
a motor to rotate the color wheel; and
a rotational position detector to emit detection light being set to fall incident on and along the retainer member so as to intermittently impinge on the open mouth portion when the color wheel is rotated, wherein the rotational position detector optically detects a rotational position of the color wheel with a reflected detection light, sensing variation in intensity thereof between the open mouth portion and the retainer member.
2. A color wheel assembly according to claim 1 , wherein the detection light impinging on the open mouth portion of the retainer member is focused upon the color filter.