Illuminating system and method for improving asymmetric projection

• US 7,290,886 B2
• Filed: 11/13/2002
• Issued: 11/06/2007
• Est. Priority Date: 11/15/2001
• Status: Expired due to Term

• Current Assignee: Young Optics, Inc.
• Original Assignee: Coretronic Corporation
• Inventors: Cheng, Chu-Ming, Kang, Yi-Hao
• Primary Examiner(s): Perkey; W. B.
• Assistant Examiner(s): Cruz; Magda
• Application Number:
  US10/065,714
• Publication Number:
  US 20030090635A1
• Time in Patent Office: 1,819 Days
• Field of Search: 353/31, 353 69- 70, 353/98, 353/81, 348/742, 348/771, 313/113, 313/114, 362/304, 359290-292
• US Class Current: 353/70
• CPC Class Codes: G03B 21/147 Optical correction of image distortions, e.g. keystone

Abstract

An illuminating system and method for improving asymmetric projection includes a light source producing a light beam to form a light path, a projection lens disposed in the light path, a light valve inserted in the light path between the light source and the projection lens, and at least one anamorphic surface unit placed in the light path between the light source and the light valve. The anamorphic surface unit offsets a distortion of a light spot resulted from obliquely incidence on the light valve, thus an asymmetric light spot can be improved as a more symmetric one to increase illuminating collection efficiency and uniformity.

Claims

1. A system for improving asymmetric projection comprising:

a light source producing a light beam to form a light path;

a projection lens which is disposed in the light path and projects an image;

a light valve inserted in the light path between the light source and the projection lens, which receives the light beam obliquely impinging from the light source to form a light spot, selects and reflects the light spot to the projection lens or predetermined directions; and

at least one anamorphic surface unit placed in the light path between the light source and the light valve, and having different curvatures on one surface to offset the distortion of the light spot resulting from obliquely impinging.

2. The system for improving asymmetric projection of claim 1, wherein the light valve is a Digital Micro-mirror Device (DMD) having an array of inclinable mirrors operated in a state selected from a group consisting of on-state, off-state, and flat-state.

3. The system for improving asymmetric projection of claim 2, wherein the anamorphic surface unit has a curvature in predeterminate axis for elongating the Y-axial length of the light spot in on-state, flat-state, and off-state in order to form non-overlapping elliptic light beams.

4. The system for improving asymmetric projection of claim 3, wherein the light valve is a Digital Micro-mirror Device (DMD) having an array of inclination mirrors operated in a state selected from a group consisting of on-state, off-state, and flat-state.

5. The system for improving asymmetric projection of claim 3, wherein the anamorphic surface unit is an anamorphic lens.

6. The system for improving asymmetric projection of claim 1, wherein the anamorphic surface unit is an anamorphic lens.

7. The system for improving asymmetric projection of claim 1, further comprising a reflector, a converging lens, a color wheel, an integration rod, a condenser lens, a relay lens, and a mirror located between the light source and the light valve,

wherein the anamorphic surface unit is selected from a group consisting of any one surface of the reflector, the converging lens, the condenser lens, the relay lens, and the mirror,

wherein the light path traveling sequentially through the reflector, the converging lens, the color wheel, the integration rod, and the condenser lens before passing through the relay lens.

8. A system for improving asymmetric projection comprising:

a light source producing a light beam to form a light path;

a projection lens which is disposed in the light path and projects an image;

a light valve inserted in the light path between the light source and the projection lens, which receives the light beam obliquely impinging from the light source to form a light spot, selects and reflects the light spot to the projection lens or predetermined directions; and

at least one anamorphic surface unit placed in the light path between the light source and the light valve, which transmits the light spot and has different curvatures on one surface to offset the distortion of the light spot resulting from obliquely impinging.

9. The system for improving asymmetric projection of claim 8, wherein the asymmetrically curved anamorphic surface unit has a curvature in predeterminate axis for elongating the Y-axial length of the light spot in on-state, flat-state, and off-state in order to form non-overlapping elliptical light beams.

10. The system for improving asymmetric projection of claim 9, wherein the light valve is a Digital Micro-mirror Device (DMD) having an array of inclinable mirrors operated in a state selected from a group consisting of on-state, off-state, and flat-state.

11. The system for improving asymmetric projection of claim 10, wherein the anamorphic surface unit has a curvature in predeterminate axis for elongating the Y-axial length of the light spot in on-state, flat-state, and off-state in order to form non-overlapping elliptic light beams.

12. The system for improving asymmetric projection of claim 9, wherein the anamorphic surface unit is an anamorphic lens.

13. The system for improving asymmetric projection of claim 8, further comprising a reflector, a converging lens, a color wheel, an integration rod, a condenser lens, a relay lens, and a mirror located between the light source and the light valve,

wherein the anamorphic surface unit is selected from a group consisting of any one surface of the reflector, the converging lens, the condenser lens, the relay lens, and the mirror,

wherein the light path traveling sequentially through the reflector, the converging lens, the color wheel, the integration rod, and the condenser lens before passing through the relay lens.

14. A system for improving asymmetric projection comprising:

a light source producing a light beam to form a light path;

at least one anamorphic surface unit placed in the light path after the light source, which transmits the light beam and has different curvatures on one surface to offset the distortion of the light beam;

a light valve inserted in the light path after the anamorphic surface unit, which receives the light beam obliquely impinging from the light source to form a light spot, selects and reflects the light spot to the projection lens or predetermined directions; and

a projection lens which is disposed in the light path after the light valve for receiving the light spot to project an image.

15. The system for improving asymmetric projection of claim 14, further comprising a reflector, a converging lens, a color wheel, an integration rod, a condenser lens, a relay lens, and a mirror located between the light source and the light valve,

wherein the anamorphic surface unit is selected from a group consisting of any one surface of the reflector, the converging lens, the condenser lens, the relay lens, and the mirror,

wherein the light path traveling sequentially through the reflector, the converging lens, the color wheel, the integration rod, and the condenser lens before passing through the relay lens.