Screen and image projection apparatus
Light emitted from a light source is modulated and projected on a screen. The screen includes a securing member, a diffuser plate supported by the securing member using a plurality of elastic members, where the elastic members are disposed so that the diffuser plate is resiliently displaced in two directions in the plane of the diffuser plate, and a driving unit that moves the diffuser plate with respect to the securing member in the two directions in the plane of the diffuser plate.
1. A screen onto which modulated light emitted from a light source is projected, the screen comprising:
a securing member;
a diffuser plate supported by the securing member using a plurality of elastic members, the plurality of elastic members being disposed so that the diffuser plate is resiliently displaced in two directions in a plane of the diffuser plate, wherein the plurality of elastic members include at least two leaf springs and wherein at least one of the at least two leaf springs is disposed so that a length direction thereof is directed along one of the two directions, and at least one other of the at least two leaf springs is disposed so that a length direction thereof is directed along the other of the two directions, and width directions of the at least two leaf springs are directed along an optical axis of the modulated light emitted from the light source; and
first and second voice coil motors that move the diffuser plate with respect to the securing member in the two directions in the plane of the diffuser plate, wherein a sine-wave voltage applied to the first voice coil motor has a ninety degree phase difference with respect to a sine-wave voltage applied to the second voice coil motor, each of the first and second voice coil motors comprising a magnet secured to the securing member, a yoke secured to the securing member, and a coil secured to the diffuser plate.
2. The screen according to claim 1 , wherein the diffuser plate is indirectly supported by the securing member using a connecting member disposed between the plurality of elastic members.
3. The screen according to claim 1 , wherein the two directions represent a horizontal direction and a vertical direction of the screen.
4. An image projection apparatus comprising:
a light source for emitting light;
a screen including a securing member, a diffuser plate, and first and second voice coil motors; and
a light modulation unit configured to modulate the light emitted from the light source and project the light onto the screen so as to display an image,
wherein the diffuser plate is supported by the securing member using a plurality of elastic members, the plurality of elastic members are disposed so that the diffuser plate is resiliently displaced in two directions in a plane of the diffuser plate, the plurality of elastic members include at least two leaf springs, wherein at least one of the at least two leaf springs is disposed so that a length direction thereof is directed along one of the two directions, and at least one other of the at least two leaf springs is disposed so that a length direction thereof is directed along the other of the two directions, and width directions of the at least two leaf springs are directed along an optical axis of the modulated light emitted from the light source, the first and second voice coil motors move the diffuser plate with respect to the securing member in the two directions in the plane of the diffuser plate, and wherein a sine-wave voltage applied to the first voice coil motor has a ninety degree phase difference with respect to a sine-wave voltage applied to the second voice coil motor, each of the first and second voice coil motors comprising a magnet secured to the securing member, a yoke secured to the securing member, and a coil secured to the diffuser plate.
5. The screen according to claim 1 , wherein the first voice coil motor moves the diffuser plate in one of the two directions and the second voice coil motor moves the diffuser plate in the other of the two directions.