Optical assembly for a wide field of view point action camera with low field curvature
An optical assembly for a point action camera with a wide field of view includes multiple lens elements configured to provide a field of view in excess of 150 degrees. One or more lens elements has an aspheric surface. The optical assembly exhibits a low inward field curvature of less than 75 microns.
1. An optical assembly for a point action camera having a wide field of view, comprising multiple lens elements including an aspheric surface, configured to provide a field of view in excess of 150 degrees that comprises an inward field curvature of less than 75 microns, wherein the optical assembly comprises from object end to image end:
(a) a first convexo-concave or meniscus lens;
(b) a second convexo-concave or meniscus lens;
(c) a biconvex lens;
(d) an aperture stop;
(e) a concavo-convex meniscus lens;
(f) a convexo-concave lens;
(g) a biconvex lens; and
(h) a biaspheric lens.
2. The optical assembly of claim 1 , wherein the inward field curvature comprises less than 60 microns.
3. The optical assembly of claim 1 , wherein the inward field curvature comprises approximately 50 microns or less.
4. The optical assembly of claim 1 , wherein the optical assembly has a longitudinal astigmatism that comprises approximately 0.7 mm or less.
5. The optical assembly of claim 1 , wherein the optical assembly has a longitudinal astigmatism that comprises approximately 0.5 mm or less.
6. The optical assembly of claim 1 , wherein the optical assembly has a longitudinal astigmatism that comprises approximately 0.3 mm or less.
7. The optical assembly of claim 1 , wherein the optical assembly has a longitudinal astigmatism that approximately 0.2 mm or less.
8. The optical assembly of claim 1 , wherein the optical assembly has a longitudinal astigmatism that comprises approximately 0.1 mm or less.
9. The optical assembly of claim 1 , wherein said biaspheric lens comprises a biconvex lens.
10. The optical assembly of claim 1 , wherein said (f) convexo-concave lens and said (g) biconvex lens comprise a doublet.
11. The optical assembly of claim 1 , wherein the lateral chromatic aberration is less than approximately five microns.
12. The optical assembly of claim 1 , wherein the lateral chromatic aberration is less than approximately three microns.
13. A digital camera, comprising
an optical assembly as in claim 1 ; and
an image sensor disposed approximately at a focal plane of the optical assembly; and
a digital camera housing including electronics and a user interface, and containing said optical assembly and said image sensor in optically effective relative disposition.
14. The digital camera of claim 13 , wherein the inward field curvature comprises less than 60 microns.
15. The digital camera of claim 13 , wherein the inward field curvature comprises approximately 50 microns or less.
16. The digital camera of claim 13 , wherein the optical assembly has a longitudinal astigmatism that comprises approximately 0.7 mm or less.
17. The digital camera of claim 13 , wherein the optical assembly has a longitudinal astigmatism that comprises approximately 0.5 mm or less.
18. The digital camera of claim 13 , wherein the optical assembly has a longitudinal astigmatism that comprises approximately 0.3 mm or less.
19. The digital camera of claim 13 , wherein the optical assembly has a longitudinal astigmatism that approximately 0.2 mm or less.
20. The digital camera of claim 13 , wherein the optical assembly has a longitudinal astigmatism that comprises approximately 0.1 mm or less.
21. The digital camera of claim 13 , wherein said biaspheric lens comprises a biconvex lens.
22. The digital camera of claim 13 , wherein said (f) convexo-concave lens and said (g) biconvex lens comprise a doublet.
23. The digital camera of claim 13 , wherein the lateral chromatic aberration is less than approximately five microns.
24. The digital camera of claim 13 , wherein the lateral chromatic aberration is less than approximately three microns.