OPTICAL UNIT, PROJECTION DISPLAY APPARATUS, AND OPTICAL DIFFUSER
First Claim
1. A projection display apparatus including a light source that emits light having coherency, an imager that modulates the light emitted from the light source, and a projection unit that projects light emitted from the imager onto a projection surface, the projection display apparatus comprising:
- a speckle noise reduction element provided between the light source and the imager; and
a control unit that controls a first mode and a second mode, whereinthe control unit controls the speckle noise reduction element so that speckle noise is reduced in the first mode than in the second mode.
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Accused Products
Abstract
Disclosed is a projection display apparatus which is provided with: a light source (110) which emits light having coherency; a light modulation element (500), which modules the light emitted from the light source; and a projection unit (150) which projects, to a projection plane, the light emitted from the light modulation element. The projection display apparatus is also provided with a speckle noise reducing element (600) provided between the light source and the light modulation element, and a control unit which controls first mode and second mode. The control unit controls the speckle noise reducing element so that speckles are reduced in the first mode compared with those in the second mode.
19 Citations
16 Claims
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1. A projection display apparatus including a light source that emits light having coherency, an imager that modulates the light emitted from the light source, and a projection unit that projects light emitted from the imager onto a projection surface, the projection display apparatus comprising:
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a speckle noise reduction element provided between the light source and the imager; and a control unit that controls a first mode and a second mode, wherein the control unit controls the speckle noise reduction element so that speckle noise is reduced in the first mode than in the second mode. - View Dependent Claims (2, 3, 4, 5, 6, 7, 9, 10, 11, 15)
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8. An optical diffuser that diffuses light having coherency and transmit the light having coherency, the optical diffuser comprising:
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a first rotating member that rotates about a first rotating axis; a second rotating member that rotates about a second rotating axis parallel to the first rotating axis; and a belt-like diffusion sheet wound around the first rotating member and the second rotating member in an endless loop, wherein the belt-like diffusion sheet constitutes two diffusion surfaces that move in a reverse direction.
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12. An optical diffuser that diffuses light having coherency and has a diffusion area through which the light having coherency passes, wherein
the diffusion area includes a center area having an optical axis center of the light having coherency and a peripheral area provided around the center area, and a diffusion degree of the center area is larger than a diffusion degree of the peripheral area.
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13. An optical unit comprising:
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a pair of lens arrays; and a vibration applying unit that periodically moves the pair of lens arrays.
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14. An optical unit, wherein
the pair of lens arrays comprise: - a first lens array with a focal distance f; and
a second lens array with a focal distance f′
,the focal distance f and the focal distance f′
satisfies f≦
f′
, andwhen a medium with an absolute refractive index n is interposed between the first lens array and the second lens array, an interval between the first lens array and the second lens array is approximately (f+f)/n. - View Dependent Claims (16)
- a first lens array with a focal distance f; and
Specification