Relay lens system for broadband imaging
An optical system includes a first relay rod of a first material, a second relay rod of a second material, different from the first material, and a lens between the first and second relay rods.
1. An optical system, comprising:
a first relay rod of a first material, the first relay rod having no optical power;
a second relay rod of a second material, different from the first material, the second relay rod having no optical power, wherein the first and second relay rods are geometrically symmetric to one another relative to a pupil or conjugate pupil of the optical system, the first and second relay rods having a same length; and
a lens between the first and second relay rods, wherein the lens includes a first relay objective and a second relay objective that have a same design and material.
2. The optical system as claimed in claim 1 , wherein the first and second materials are selected to reduce the wavefront error across the field of view of the optical system as compared with using a same material for both the first and second relay rods.
3. The optical system as claimed in claim 1 , wherein a pupil region of the system is in air.
4. The optical system as claimed in claim 1 , further comprising:
a third relay rod of a third material;
a fourth relay rod of a fourth material, the fourth material being different from the third material; and
a lens between the third and fourth relay rods.
5. The optical system as claimed in claim 4 , wherein the first and third materials are the same and the second and fourth materials are the same.
6. The optical system as claimed in claim 1 , further comprising a detector to detect light from 460 nm to 850 nm.
7. An endoscope including the optical system as claimed in claim 1 .
8. The optical system as claimed in claim 1 , wherein the first and second relay rods and the lens has refractive index symmetry and Abbe number asymmetry about a pupil region.
9. A kit, comprising:
a first relay rod of a first material, the first relay rod having no optical power;
a second relay rod of a second material, different from the first material, the second relay rod having no optical power, wherein the first and second relay rods are geometrically symmetric to one another relative to a pupil or conjugate pupil of the optical system, the first and second relay rods having a same length; and
a lens to be inserted between the first and second relay rods, wherein the lens includes a first relay objective and a second relay objective that have a same design and material.
10. The kit as claimed in claim 9 , wherein the lens includes a first relay objective and a second relay objective.
11. The kit as claimed in claim 10 , wherein the first and second relay objectives have a same design and material.
12. The kit as claimed in claim 9 , wherein the first and second relay rods and the lens has refractive index symmetry and Abbe number asymmetry about a pupil region.
13. A method of compensating for dispersion in a relay lens system, the method comprising:
providing a first relay rod of a first material, the first relay rod having no optical power;
providing a second relay rod of a second material, different from the first material, the second relay rod having no optical power, wherein the first and second relay rods are geometrically symmetric to one another relative to a pupil or conjugate pupil of the optical system, the first and second relay rods having a same length; and
providing a lens between the first and second relay rods, wherein the lens includes a first relay objective and a second relay objective that have a same design and material.
14. The method as claimed in claim 13 , wherein the first and second relay rods and the lens has refractive index symmetry and Abbe number asymmetry about a pupil region.