Multi-channel sensor using a rear-stopped reflective triplet

1. An optical sensor system having an aperture stop and an optical axis and configured to provide images of objects, the system comprising:

a primary mirror configured to receive electromagnetic radiation from the objects;

a secondary mirror configured to receive the electromagnetic radiation reflected from the primary mirror;

a tertiary mirror configured to receive the electromagnetic radiation reflected from the secondary mirror;

a dichroic beamsplitter configured to direct electromagnetic radiation from a first spectrum along a first axis and to direct electromagnetic radiation from a second spectrum along a second axis;

a first image plane configured to receive the electromagnetic radiation from the first spectrum along the first axis to form a first image of the objects;

a second image plane configured to receive the electromagnetic radiation from the second spectrum along the second axis to form a second image of the objects;

a first transmitting aperture stop positioned between the dichroic beamsplitter and the first image plane; and

a second transmitting aperture stop positioned between the dichroic beamsplitter and the second image plane,

wherein the first transmitting aperture stop and the second transmitting aperture stop are each located at a rear pupil of the optical sensor system.

2. The optical sensor system of claim 1 , wherein the first transmitting aperture stop is further positioned slightly above and to the right of the secondary mirror.

3. The optical sensor system of claim 2 , wherein the second transmitting aperture stop is further positioned slightly above and to the left of the secondary mirror.

4. The optical sensor system of claim 1 , wherein electromagnetic radiation from the first spectrum is visible light and electromagnetic radiation from the second spectrum is IR light.

5. The optical sensor system of claim 1 , wherein electromagnetic radiation from the first spectrum is directed to the first image plane by a first mirror.

6. The optical sensor system of claim 5 , wherein electromagnetic radiation from the second spectrum is directed to the second image plane by a second mirror.

7. The optical sensor system of claim 1 , wherein the three mirrors constitute a reflective triplet optical form,

wherein the dichroic beamsplitter is subsequent to the tertiary mirror,

wherein at least one transmitting aperture stop is subsequent to the dichroic beamsplitter, and

wherein a subsequent final scene image or images formed are subsequent to the at least one transmitting aperture stop, and are the only scene image or images formed by the optical system.

8. The optical sensor system of claim 1 , wherein the primary, secondary and tertiary mirrors are off-axis from the optical axis of the optical sensor system, and wherein the primary mirror is a positive power mirror, the secondary mirror is a negative power mirror, and the tertiary mirror is a positive power mirror.

9. A method of imaging objects in an optical sensor system, the method comprising:

reflecting electromagnetic radiation received from objects in a first direction relative to an optical axis utilizing a primary mirror;

reflecting the electromagnetic radiation received from the primary mirror in a second direction relative to the optical axis utilizing a secondary mirror;

reflecting the electromagnetic radiation received from the secondary mirror in a third direction relative to the optical axis utilizing a tertiary mirror;

directing electromagnetic radiation from a first spectrum along a first axis;

directing electromagnetic radiation from a second spectrum along a second axis;

forming a first image of distant objects from electromagnetic radiation from the first spectrum along the first axis with a first image plane; and

forming a second image of the distant objects from electromagnetic radiation from the second spectrum along the second axis with a second image plane,

wherein a first transmitting aperture stop is positioned between a dichroic beamsplitter and the first image plane,

wherein a second transmitting aperture stop is positioned between a dichroic beamsplitter and the second image plane, and

wherein the first transmitting aperture stop and the second transmitting aperture stop are each located at a rear pupil of the optical sensor system.

10. The method of claim 9 , wherein the first transmitting aperture stop is further positioned slightly above and to the right of the secondary mirror.

11. The method of claim 10 , wherein the second transmitting aperture stop is further positioned slightly above and to the left of the secondary mirror.

12. The method of claim 9 , wherein electromagnetic radiation from the first spectrum is visible light and electromagnetic radiation from the second spectrum is IR light.

13. The method of claim 9 , further comprising directing electromagnetic radiation from the first spectrum to the first image plane by a first mirror.

14. The method of claim 13 , further comprising directing electromagnetic radiation from the second spectrum to the second image plane by a second mirror.

15. The method of claim 9 , wherein the three mirrors constitute a reflective triplet optical form,

wherein the dichroic beamsplitter is subsequent to the tertiary mirror,

wherein at least one transmitting aperture stop is subsequent to the dichroic beamsplitter, and

wherein a subsequent final scene image or images formed are subsequent to the at least one transmitting aperture stop, and are the only scene image or images formed by the optical system.

16. The method of claim 9 , wherein the primary, secondary and tertiary mirrors are off-axis from the optical axis of the optical sensor system, and wherein the primary mirror is a positive power mirror, the secondary mirror is a negative power mirror, and the tertiary mirror is a positive power mirror.