Multi-channel wide field imaging system and optical system for use therein
View Patent ↗An optical system for use with a multi-channel wide field imaging system, the optical system including an objective lens, a dichroic element to split light into a first wavelength range and a second wavelength range, the dichroic element positioned to receive near parallel chief rays from the objective lens, a first channel lens system to receive light of the first wavelength range from the dichroic element; and a second channel lens system to receive light of the second wavelength range from the dichroic element.
1. An optical system for use with a multi-channel wide field imaging system, the optical system comprising:
an objective lens;
a dichroic element to split light into a first wavelength range and a second wavelength range, the dichroic element positioned to receive near parallel chief rays from the objective lens;
a first channel lens system to receive light of the first wavelength range from the dichroic element; and
a second channel lens system to receive light of the second wavelength range from the dichroic element, wherein
the first wavelength range is in the visible region and the second wavelength range is outside the visible region, and
lens elements of the first and second channel lens systems have identical lens prescriptions.
2. The optical system as claimed in claim 1 , wherein the objective lens is to output marginal rays that are within a cone half angle requirement for the dichroic element.
3. The optical system as claimed in claim 1 , wherein the first wavelength range and the second wavelength range have intensities that differ by at least one order of magnitude.
4. The optical system as claimed in claim 3 , wherein the second wavelength range has a lower intensity than the first wavelength range and an aperture stop of the second channel lens system is larger than an aperture stop in the first channel lens system.
5. The optical system as claimed in claim 1 , wherein the dichroic element is before a limiting aperture in the optical system.
6. The optical system as claimed in claim 5 , wherein the first and second channel lens systems have separate and independent limiting apertures.
7. The optical system as claimed in claim 1 , wherein the first and second channel lens systems, in combination with the common objective lens, have a retro-focus form.
8. The optical system as claimed in claim 1 , wherein the optical system is image space telecentric or near telecentric.
9. The optical system as claimed in claim 1 , further comprising another dichroic beam splitter in one of the first and second channel lens systems outputting light to a third channel lens system.
10. The optical system as claimed in claim 9 , wherein lenses in the first channel lens system, in the second channel lens system, and in the third channel lens system have identical lens prescriptions.
11. The optical system as claimed in claim 10 , wherein each of the second channel lens system and the third channel lens system has an aperture stop that is larger than an aperture stop in the first channel lens system, aperture stops for the second and third channel lens systems having a same size.
12. The optical system as claimed in claim 1 , wherein an aperture stop of the first channel lens system is different from an aperture stop of the second channel lens system.
13. The optical system as claimed in claim 12 , wherein the aperture stop of the first channel lens system is smaller than the aperture stop of the second channel lens system.
14. The optical system as claimed in claim 12 , wherein the aperture stop of the first channel lens system is an opening having simple geometry and the aperture stop of the second channel lens system is a Fourier aperture.
15. An imaging system, comprising:
an optical system as claimed in claim 1 ; and
respective image sensors in respective channels to detect corresponding wavelength ranges in each channel lens system.
16. A kit, comprising:
an objective lens;
a dichroic element to split light into a first wavelength range and a second wavelength range;
a first channel lens system to receive light of the first wavelength range; and
a second channel lens system to receive light of the second wavelength, the first and second channel lens systems having identical lens prescriptions, wherein the first wavelength range is in the visible region and the second wavelength range is outside the visible region.
17. The kit as claimed in claim 16 , wherein an aperture stop of the first channel lens system is different from an aperture stop of the second channel lens system.
18. The kit as claimed in claim 17 , wherein the aperture stop of the first channel lens system is smaller than the aperture stop of the second channel lens system.
19. The kit as claimed in claim 17 , wherein the aperture stop of the first channel lens system is an opening having simple geometry and the aperture stop of the second channel lens system is a Fourier aperture.
20. A method of imaging multi-channel wide field light, the method comprising:
providing all light to be imaged incident on a common objective lens;
splitting light from the common objective lens by a dichroic element into a first wavelength range and a second wavelength range, the dichroic element being in a position relative to the common objective lens such that the dichroic element receives sufficiently parallel chief rays;
providing light of the first wavelength range from the dichroic element to a first channel; and
providing light of the second wavelength range from the dichroic element to a second channel, wherein
the first wavelength range is in the visible region and the second wavelength range is outside the visible region, and
lens elements of the first and second channel lens systems have identical lens prescriptions.