Aberration correction

Patent metadata

Field	Value
Publication number	US-10310256-B2
Application number	US-201615210031-A
Country	US
Kind code	B2
Filing date	Jul 14, 2016
Priority date	Jul 14, 2016
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

A beamsplitter includes an optical substrate with a first surface configured to receive a beam of multi-spectral light, to reflect a first band of the multi-spectral light and to transmit a second band of the multi-spectral light through the optical substrate to be emitted from a second surface of the optical substrate opposite the first surface. The second surface is a freeform surface. A system includes a telescope configured to focus multi-spectral light into a beam. The system also includes a beamsplitter as described above optically coupled to the telescope so the first surface of the beamsplitter is configured to receive the beam of multi-spectral light from the telescope.

First claim

What is claimed is:

1. A system comprising:
a telescope configured to focus multi-spectral light into a beam; and
a beamsplitter optically coupled to the telescope, wherein the beamsplitter includes an optical substrate with a first surface configured to receive a beam of multi-spectral light from the telescope, to reflect a first band of the multi-spectral light and to transmit a second band of the multi-spectral light through the optical substrate to be emitted from a second surface of the optical substrate opposite the first surface, wherein the second surface is a freeform surface, further comprising a first imaging sensor optically coupled to receive the first band reflected from the beamsplitter, and a second imaging sensor optically coupled to receive the second band transmitted through the beamsplitter, wherein the telescope is a catadioptric telescope, and wherein there are no non-axiosymmetric aberration components for correction between the beamsplitter and the second image sensor.

2. A system as recited in claim 1 , wherein the freeform surface is configured to mitigate aberration in the second band emitted from the second surface of the optical substrate.

3. A system as recited in claim 2 , wherein the freeform surface is non-axiosymmetric.

4. A system as recited in claim 1 , wherein the first surface is configured to reflect a first band of wavelengths within a range from long wave infrared (LWIR) to visible, inclusive, and to transmit a second band of wavelengths within a range from LWIR to visible, inclusive.

5. A system as recited in claim 1 , further comprising a fold mirror optically coupling the telescope to the beamsplitter.

6. A system as recited in claim 1 , wherein there is a focus after the beamsplitter that is an intermediate image, wherein there are no off-axis components for aberration correction between the beamsplitter and the second imaging sensor.

7. A system as recited in claim 1 , wherein the second imaging sensor is sensitive in an infrared band.

8. A system as recited in claim 1 , wherein an image is formed on the second imaging sensor, wherein the image is free of aberrations.

9. A system as recited in claim 1 , wherein the second imaging sensor is free from non-axiosymmetric aberration components.

Assignees

• Goodrich Corp

Inventors

• Johnson James B
• Tejada John Anthony

Classifications

• G02B27/0025 Primary

  for optical correction, e.g. distorsion, aberration · CPC title

• G02B27/1013

  for colour or multispectral image sensors, e.g. splitting an image into monochromatic image components on respective sensors (spectral imaging systems G01J) · CPC title

• G02B23/04

  for the purpose of beam splitting or combining, e.g. fitted with eyepieces for more than one observer (G02B23/10 takes precedence) · CPC title