Multi-channel folded optical system

Patent metadata

Field	Value
Publication number	US-11287635-B2
Application number	US-201916455001-A
Country	US
Kind code	B2
Filing date	Jun 27, 2019
Priority date	Jun 27, 2018
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

An optical system such as an imaging system, projecting system or combined imaging and projecting system, has complex dielectric coatings and/or reflecting polarizers to separate multiple spectral bands and/or polarizations on one or more of the system's curved mirrors.

First claim

What is claimed is:

1. An optical system, comprising:
a first mirror substrate having a primary mirror and a tertiary mirror;
a second mirror substrate opposing the first mirror substrate and having a secondary mirror and a quaternary mirror; and
a piston for translating the second mirror substrate relative to the first mirror substrate; and
wherein the primary mirror and the tertiary mirror are aspheric and the secondary mirror and the quaternary mirror are flat or spherical.

2. The optical system of claim 1 , wherein the optical system is an imaging system, projecting system or combined imaging and projecting system.

3. The optical system of claim 1 , further comprising a complex dielectric coating comprising at least one dichroic mirror separated from another mirror by a separation layer.

4. The optical system of claim 1 , further comprising a complex dielectric coating comprising at least a first dichroic mirror, separated from a second dichroic mirror separated from another mirror by respective separation layers.

5. The optical system of claim 1 , further comprising a lens for conditioning light passing through an aperture in the first mirror substrate.

6. The optical system of claim 1 , further comprising a lens for conditioning light passing through an aperture in the first mirror substrate, wherein the lens has at least one aspheric surface.

7. The optical system of claim 1 , further comprising a baffle between the primary mirror and the tertiary mirror.

8. The optical system of claim 1 , further comprising a baffle between the secondary mirror and the quaternary mirror.

9. The optical system of claim 1 , further comprising a detector assembly comprising one or more beamsplitters and two or more image sensors.

10. The optical system of claim 1 , further comprising an articulated fold mirror, or prism, mounted in front of the optical system.

11. The optical system of claim 1 , further comprising a Risley prism mounted in front of the mirror system.

12. The optical system of claim 1 , operating as a multi-band star tracker.

13. The optical system of claim 1 , further comprising a patterned optical surface on at least one of the mirrors.

14. The optical system of claim 1 , wherein the optical system has a segmented-circular profile.

15. An imaging system, comprising:
a first mirror substrate having an aspheric primary mirror and an aspheric tertiary mirror;
a second mirror substrate opposing the first mirror substrate and having a spherical secondary mirror and a spherical quaternary mirror; and
a piston for translating the second mirror substrate relative to the first mirror substrate.

16. The imaging system of claim 15 , wherein the primary mirror comprises a complex dielectric coating comprising at least one dichroic mirror separated from another mirror by a separation layer.

17. The imaging system of claim 15 , wherein the primary mirror comprises a complex dielectric coating comprising at least a first dichroic mirror, separated from a second dichroic mirror separated from another mirror by respective separation layers.

18. The imaging system of claim 15 , further comprising a detector assembly comprising one or more beamsplitters and two or more image sensors.

19. An optical system, comprising:
a first mirror substrate having a primary mirror and a tertiary mirror;
a first baffle between the primary mirror and the tertiary mirror;
a second mirror substrate opposing the first mirror substrate and having a secondary mirror and a quaternary mirror;
a second baffle between the secondary mirror and the quaternary mirror; and
a piston for translating the second mirror substrate relative to the first mirror substrate;
wherein the primary mirror and the tertiary mirror are aspheric and the secondary mirror and the quaternary mirror are flat or spheric.

20. The optical system of claim 19 , further comprising:
a first beamsplitter for splitting off a visible band to a visible image sensor of light from the quanternary mirror;
a second beamsplitter for splitting off short wave infrared and near infrared light to a SWIR/NIR image sensor of light from the first beamsplitter;
a third beamsplitter for splitting off mid-wave infrared light to a MWIR image sensor of light from the second beamsplitter; and
a long wave infrared image sensor for detecting light received from the third beamsplitter.

Assignees

• Charles Stark Draper Laboratory Inc

Inventors

• Sinclair Matthew A
• Bohn Paul Aaron
• Laine Juha-Pekka
• Rogomentich Francis J

Classifications

• G02B17/0808 Primary

  on-axis systems with at least one of the mirrors having a central aperture · CPC title

• H04N23/45

  for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images · CPC title

• H04N23/55

  Optical parts specially adapted for electronic image sensors; Mounting thereof · CPC title

• G02B17/0824

  on-axis systems with at least one of the mirrors having a central aperture · CPC title

• G02B5/0825

  the reflecting layers comprising dielectric materials only · CPC title