BEAM ALIGNMENT SYSTEM USING ARRAYED LIGHT SOURCES

• US 20100302514A1
• Filed: 05/28/2009
• Published: 12/02/2010
• Est. Priority Date: 05/28/2009
• Status: Active Grant

• Current Assignee: IMAX Theatres International Limited (IMAX Corporation)
• Original Assignee: Eastman Kodak Company
• Inventors: Kircher, James R., Silverstein, Barry D., Harland, Mark A.
• Granted Patent: US 8,033,666 B2
• Time in Patent Office: Days
• US Class Current: 353/37
• CPC Class Codes: G02B 27/1026 for use with reflective spatial light modulators
• CPC Class Codes: G02B 27/1073 characterized by manufacturing or alignment methods
• CPC Class Codes: G02B 27/126 The splitting element being a prism or prismatic array, including systems based on total internal reflection
• CPC Class Codes: G02B 27/143 using macroscopically faceted or segmented reflective surfaces
• CPC Class Codes: G02B 27/149 using crossed beamsplitting surfaces, e.g. cross-dichroic cubes or X-cubes
• CPC Class Codes: H01S 5/005 Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping H01S5/026, H01S5/18388 take precedence
• CPC Class Codes: H01S 5/4087 emitting more than one wavelength

Abstract

A beam alignment system for generating an aligned two-dimensional array of parallel light beams, comprising a beam alignment chamber including a base extending in a length direction and a plurality of reflectors mounted on the base, each having independent yaw and pitch adjustments. The beam alignment system further includes a plurality of arrays of light sources, each generating an array of light beams and being paired with a corresponding reflector, the reflectors being disposed to direct the light beams along the length of the beam alignment chamber forming an aligned two-dimensional array of parallel light beams.

Claims

1. A beam alignment system for generating an aligned two-dimensional array of parallel light beams, comprising:

a) a beam alignment chamber including;

i) a base, the base extending in a length direction having a front edge, a first side edge and a second side edge; and

ii) a plurality of reflectors mounted on the base, each having independent yaw and pitch adjustments; and

b) a plurality of arrays of light sources, each array of light sources generating an array of light beams and being paired with a corresponding reflector and being disposed to direct the light beams onto its corresponding reflector, and wherein the reflectors are disposed to direct the light beams along the length of the beam alignment chamber forming an aligned two-dimensional array of parallel light beams.

2. The beam alignment system of claim 1 wherein the arrays of light sources are mounted external to the beam alignment chamber and are disposed to direct light into the beam alignment chamber and onto the corresponding base-mounted reflectors.

3. The beam alignment system of claim 2 wherein some of the arrays of light sources are positioned on a first side of the beam alignment chamber and the remaining arrays of light sources are positioned on a second side of the beam alignment chamber opposed to the first side of the beam alignment chamber.

4. The beam alignment system of claim 1 wherein the beam alignment chamber further includes a cover spaced apart from the base, together with a plurality of reflectors mounted to the cover, each cover-mounted reflector having independent yaw and pitch adjustments, and wherein each cover-mounted reflector is paired with a corresponding array of light sources generating an array of light beams and is disposed to direct the light beams along the length of the beam alignment chamber, forming the aligned two-dimensional array of parallel light beams in cooperation with the light beams associated with the base-mounted reflectors.

5. The beam alignment system of claim 4 wherein adjustment holes are provided in the cover to access the independent yaw and pitch adjustments for both the cover-mounted reflectors and the base-mounted reflectors.

6. The beam alignment system of claim 1 wherein each light beam entering the beam alignment chamber is uncorrected for divergence with respect to at least one axis, and further including one or more optical elements positioned in the optical path of the aligned two-dimensional array of light beams disposed to correct the beam divergence with respect to at least one axis, and wherein the light sources are positioned so that the optical distance between each light source and the one or more optical elements is substantially equal for each of the light beams.

7. The beam alignment system of claim 6 wherein the corrected aligned two-dimensional array of light beams is collimated.

8. The beam alignment system of claim 6 wherein the one or more optical elements comprise a cylinder lens providing correction for the beam divergence with respect to one axis.

9. The beam alignment system of claim 6 wherein the one or more optical elements comprise a pair of crossed cylinder lenses providing correction for the beam divergence with respect to two axes.

10. The beam alignment system of claim 1 wherein each light beam entering the beam combining chamber is uncorrected for divergence with respect to at least one axis, and wherein the reflectors are cylindrical reflectors that correct the beam divergence with respect to one axis.

11. The beam alignment system of claim 1 wherein the light sources are laser light sources.

12. The beam alignment system of claim 1 wherein the beam alignment chamber is open, having no side walls connected to the first side edge of the base or the second side edge of the base.

13. The beam alignment system of claim 1 wherein the beam alignment chamber is open, having no side walls connected to any edges of the base.

14. The beam alignment system of claim 1 wherein the beam alignment system is a component of a laser source system that provides a two-dimensional array of parallel laser beams for use in a laser projection system, and wherein the laser projection system further comprises:

an illumination system configured to uniformize laser light it receives;

an image forming system configured to interact with laser light that has been both uniformized by the illumination system; and

a projection system configured to project the laser light image onto a viewing screen.