Optical system with reflection-angle-selective mirror

• US 7,108,383 B1
• Filed: 03/29/2005
• Issued: 09/19/2006
• Est. Priority Date: 04/22/2004
• Status: Expired due to Fees

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Mitchell, Daniel Bruce
• Primary Examiner(s): Ben, Loha
• Assistant Examiner(s): Dinh, Jack
• Application Number:
  US11/093,822
• Time in Patent Office: 539 Days
• Field of Search: 359/577, 359/584, 359586-589, 359/839, 359/884, 359/359, 359/597, 359/601, 359/602, 359/613, 359/629, 359/634
• US Class Current: 359/839
• CPC Class Codes: G02B 27/1033 having a single light modulator for all colour channels
• CPC Class Codes: G02B 27/142 Coating structures, e.g. thin films multilayers
• CPC Class Codes: G03B 21/14 Details

Abstract

An optical system includes a reflection-angle-selective mirror having a substrate, and a reflection-angle-selective coating structure deposited on the substrate. The reflection-angle-selective coating structure has a higher reflectance for light that is incident upon the reflection-angle-selective coating structure at a first incidence angle within an acceptance-angle deviation from a design incidence angle than for light that is incident upon the reflection-angle-selective coating structure at a second incidence angle greater than the acceptance-angle deviation from the design incidence angle. The optical system may also include a light source.

Claims

1. An optical system comprising a reflection-angle-selective mirror, wherein the reflection-angle-selective mirror includes:

a substrate; and

a reflection-angle-selective coating structure deposited on the substrate, wherein the reflection-angle-selective coating structure has a higher reflectance for light that is incident upon the reflection-angle-selective coating structure at a first incidence angle within an acceptance-angle deviation from a design incidence angle than for light that is incident upon the reflection-angle-selective coating structure at a second incidence angle greater than the acceptance-angle deviation from the design incidence angle, wherein the reflection-angle-selective coating structure comprises a plurality of alternating layers of at least two different materials that are each transparent to a selected wavelength of light.

2. The optical system of claim 1, wherein at least some of the layers are of differing thicknesses.

3. The optical system of claim 1, wherein the substrate is transparent to the selected wavelength of light.

4. The optical system of claim 1, wherein the substrate absorbs light that is incident upon the reflection-angle-selective coating structure at the second incidence angle greater than the acceptance-angle deviation from the design incidence angle.

5. The optical system of claim 1, further including

a light source that directs a primary beam of light that is incident upon the reflection-angle-selective mirror at a source incidence angle within the acceptance-angle deviation from the design incidence angle.

6. The optical system of claim 1, further including

a laser light source that directs a primary beam of light that is incident upon the reflection-angle-selective mirror at a source incidence angle within the acceptance-angle deviation from the design incidence angle.

7. The optical system of claim 1, further including

at least one additional mirror in a cooperative optical relationship with the reflection-angle-selective mirror.

8. The optical system of claim 1, further including

at least one refractive optical component in a cooperative optical relationship with the reflection-angle-selective mirror.