Micro-Optical Device, Spatial Optical Modulator and Projector Utilizing the Micro-Optical Device

• US 20080094718A1
• Filed: 12/08/2005
• Published: 04/24/2008
• Est. Priority Date: 06/10/2005
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Takaura, Atsushi, Fujita, Kazuhiro, Miyagaki, Kazuya, Osaka, Takanobu
• Granted Patent: US 7,561,336 B2
• Time in Patent Office: Days
• US Class Current: 359/626
• CPC Class Codes: G03B 21/005 Projectors using an electronic spatial light modulator but not peculiar thereto
• CPC Class Codes: H04N 5/7441 the modulator being an array of liquid crystal cells

Abstract

A micro-optical device includes a plurality of minute optical elements each having a curved surface operable to condense incident light. The minute optical elements are arranged at constant intervals. The curved surface is expressed by two or more F values.

Claims

1. A micro-optical device comprising a plurality of minute optical elements each having a curved surface operable to condense incident light, said minute optical elements arranged at constant intervals, wherein the curved surface is expressed by two or more F values.

2. The micro-optical device as claimed in claim 1, wherein the curved surface includes substantially a flat part.

3. The micro-optical device as claimed in claim 1, wherein each of the minute optical elements is a transmission lens element having the curved surface including substantially the flat part, wherein said curved surface is convex.

4. The micro-optical device as claimed in claim 1, wherein each of the minute optical elements is a reflection mirror element having the curved surface including the substantially flat part, wherein said curved surface is concave.

5. The micro-optical device as claimed in claim 3, further comprising a translucent flat layer on the convex curved surface having the substantially flat part, wherein a member made of a material different from a material of the minute optical elements is provided between the translucent flat layer and the minute optical elements.

6. The micro-optical device as claimed in claim 1, further comprising a translucent flat layer obtained by laminating a translucent member on the concave curved surface, and flattening a surface of the translucent member.

7. The micro-optical device as claimed in claim 3, wherein the transmission lens element includes two of the F values, wherein a first F value F₁ is equal to or greater than 3.4, wherein a second F value F₂ is equal to or greater than 2.3 and equal to or less than 4.8, and wherein F₁ is greater than F₂.

8. A spatial optical modulator for performing a spatial optical modulation on light by a unit of one pixel in response to image information by utilizing the micro-optical device as claimed in claim 1 and for projecting the light as image light, wherein each of the minute optical elements is adjusted to a pixel position.

9. A spatial optical modulator for performing a spatial optical modulation on light by a unit of one pixel in response to image information by utilizing the micro-optical device as claimed in claim 3 and projecting the light as image light, wherein each of the minute optical elements is adjusted to a pixel position.

10. A projector utilizing the spatial optical modulator as claimed in claim 8, comprising a projection device configured to project the image light onto a screen, said image light projected from the spatial optical modulator.

11. The projector as claimed in claim 10, further comprising a pixel shifting device configured to shift a light path of a light flux projected from the spatial optical modulator.