Lens arrays

• US 20030112523A1
• Filed: 09/03/2002
• Published: 06/19/2003
• Est. Priority Date: 03/17/2000
• Status: Active Grant

• Current Assignee: Strategic Patent Acquisitions LLC
• Original Assignee: Stephen Daniell
• Inventors: Daniell, Stephen
• Granted Patent: US 6,721,101 B2
• Time in Patent Office: Days
• US Class Current: 359/626
• CPC Class Codes: G02B 3/0018 Reflow, i.e. characterized by the step of melting microstructures to form curved surfaces, e.g. manufacturing of moulds and surfaces for transfer etching
• CPC Class Codes: G02B 3/0025 Machining, e.g. grinding, polishing, diamond turning, manufacturing of mould parts
• CPC Class Codes: G02B 3/0031 Replication or moulding, e.g. hot embossing, UV-casting, injection moulding
• CPC Class Codes: G02B 3/0043 Inhomogeneous or irregular arrays, e.g. varying shape, size, height
• CPC Class Codes: G02B 3/005 arranged along a single direction only, e.g. lenticular sheets G02B3/0043 takes precedence
• CPC Class Codes: G02B 3/0056 arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses G02B3/0043 takes precedence; miniaturised objectives for electronic devices employing wafer level optics G02B13/0085
• CPC Class Codes: G02B 3/0062 Stacked lens arrays, i.e. refractive surfaces arranged in at least two planes, without structurally separate optical elements in-between
• CPC Class Codes: G02B 3/0068 arranged in a single integral body or plate, e.g. laminates or hybrid structures with other optical elements G02B5/1885, G02B17/002, G02B30/27 take precedence
• CPC Class Codes: G02B 3/0075 characterized by non-optical structures, e.g. having integrated holding or alignment means
• CPC Class Codes: G02B 30/27 involving lenticular arrays
• CPC Class Codes: H01L 27/14627 Microlenses
• CPC Class Codes: H04N 13/305 using lenticular lenses, e.g. arrangements of cylindrical lenses
• CPC Class Codes: H04N 13/307 using fly-eye lenses, e.g. arrangements of circular lenses
• CPC Class Codes: H04N 13/324 Colour aspects
• CPC Class Codes: H04N 13/349 Multi-view displays for displaying three or more geometrical viewpoints without viewer tracking for viewing without the aid of special glasses using fly-eye lenses H04N13/307

Abstract

Lens systems and an array of lenses for reproduction, capture and display of three dimensional images. The arrays generally fall into two categories. The first type of array uses air as the low-index material. This type of array may be used, for example, in illuminated displays electronic image detection, machine vision, and real-time 3D video capture. A second type of array uses a fluoropolymer as the low-index material, and conveys a great preponderance all incident light to the image plane.

Claims

1. A lens array comprising a plurality of joined lens elements each comprising:

a first optical boundary having a convex curvature;

a second optical boundary optically coupled and in opposition to the first optical boundary, the second optical boundary having an oblate, concave curvature; and

a third optical boundary optically coupled and in opposition to the second optical boundary, the third optical boundary having a convex curvature at least partially complementary to the curvature of the second optical boundary.

2. The lens array of claim 1 wherein the array comprises first and second interfitting members, the first member comprising the first and second surfaces of the lens elements, the first surfaces being defined on an outer side of the first member and the second surfaces being defined in alignment with the first surfaces on an inner side of the first member, the third surfaces being defined on an inner side of the second member, the lens elements thereby facilitating joinder of the inner surfaces of the first and second members such that the first, second and third surfaces of each lens elements are in optical alignment.

4. The lens array of claim 1 wherein each lens element is optically isolated from other lens elements.

5. The lens array of claim 4 wherein the array is associated with an image plane and an object plane, the lens elements comprising an optically field-limiting surface for at least one of the image plane and the object plane.

6. The lens array of claim 5 wherein each of the lens elements further comprises a fourth optical boundary defined on an outer surface of the second member.

7. The lens array of claim 1 wherein, for each lens element, the first and second boundaries are optically coupled by a first material and the second and third surfaces are optically coupled by a second material, the second material having a lower index of refraction than the first material.

8. The lens array of claim 7 wherein the second material is air.

9. The lens of claim 7 wherein the second material is a fluoropolymer.

10. The lens array of claim 1 wherein the plurality of joined lens elements is in the form of a first two-dimensional lens array component, and further comprising a second plurality of joined lens elements in the form of a second two-dimensional lens array component, each lens element of the second lens array component comprising:

a first optical boundary having a convex curvature; and

a second optical boundary optically coupled to the first optical boundary, the second optical boundary having an oblate, concave curvature,

wherein the first optical boundary of the lens elements of the first lens array component is opposed to the first optical boundary of the lenses of the second lens array component, the first and second lens array components cooperating to facilitate integral capture and reproduction of an image behind one of the arrays.

11. The lens array of claim 10 further comprising an aperture mask intervening between the first and second lens array components.

12. The lens array of claim 11 wherein the aperture mask defines non-round apertures.

13. The lens array of claim 1 wherein, for each lens element, the second optical boundary has a critical angle and a first index of refraction, each lens element further comprising a region adjacent to the second optical boundary and having an index of refraction lower than the first index of refraction, whereby each ray originating from an object point impinges the second optical boundary substantially at the critical angle.

14. The lens array of claim 2 wherein the inner surfaces of the first and second intermitting members comprise complementary raised lands in interstices between lens elements and further comprising a light-blocking cement on the raised lands, the light-blocking cement rendering the interstices substantially opaque.

15. The lens array of claim 14 wherein the lands have flat surfaces.

16. The lens array of claim 14 wherein the lands have concave surfaces.

17. The lens array of claim 2 wherein the first and second interfitting members comprise interstices between lens elements, the interstices comprising diffusive surfaces to distribute light.

18. The lens array of claim 1 wherein at least one of the boundaries comprises at least one of a conformal antireflective coating, a conformal antiabrasion coating, and a conformal heat-resistant coating.

19. The lens array of claim 18 wherein at least one of the boundaries comprises subwavelength anti-reflective microstructures.

20. The lens array of claim 1 wherein at least one of the boundaries comprises a hybrid refractive/diffractive surface.

21. The lens array of claim 2 further comprising a plurality of internal aperture stops.

22. The lens array of claim 21 wherein the internal aperture stops are disposed within interstices between the first optical boundaries.

23. The lens array of claim 22 wherein the stops are dye sublimation stops.

24. The lens array of claim 2 further comprising internal aperture stops disposed between the inner surfaces of the members and within interstices between the second and third optical boundaries.

25. The lens array of claim 2 further comprising an internal mosaic filter for color imaging.

26. The lens array of claim 1 wherein not all lens elements in the array are identical.

3. The lens array of claim 3 wherein joinder of the inner surfaces of the members causes the second and third surfaces to meet at a common perimeter.

27. A lens array comprising a plurality of joined lens elements, the lens elements each comprising a first optical boundary having a convex curvature and a second optical boundary optically coupled to the first optical boundary, the second optical boundary having an oblate, concave curvature, the lens elements cooperating to optically integrate into a single image a tiled pattern of discrete microimages.

28. The lens array of claim 27 wherein total internal reflection restricts angular emission during reproduction of the microimages.

29. The lens array of claim 27 wherein the lens elements are also tiled and further comprising a pattern of microimages associated with the fourth optical boundary, the microimages and the lens elements being tiled in different patterns.

30. The lens array of claim 29 wherein the microimages are tiled irregularly with a bias to a horizontal axis.

31. The lens array of claim 29 wherein the microimages are tiled in an irregular hexagonal pattern.

32. The lens array of claim 29 wherein the microimages are tiled in a 2:

1 rectangular pattern.

33. The lens array of claim 29 wherein the lens elements are tiled hexagonally.

34. The lens array of claim 29 wherein the lens elements have associated image center points, the microimages being displaced from the center points of the lens elements.

35. The lens array of claim 34 wherein the microimages are radially shifted inwardly relative to the image center points.

36. The lens array of claim 29 wherein the microimages contain null zones not enabled to capture or reproduce light.

37. The lens array of claim 29 wherein the microimages define a time-distorted image set.

38. The lens array of claim 29 wherein the microimages define at least two planes of graphic material at differing focal lengths.

39. The lens array of claim 29 wherein the microimages are displaceable from the fourth optical boundary, permitting relative motion therebetween.

40. The lens array of claim 39 wherein the lens elements cause the microimages to undergo an optical magnification of about 1.25 during reproduction.