OPTICAL ELEMENT HAVING A RANDOMIZING DIGITAL LENS ARRAY AND/OR A DIFFUSER FUNCTION
This application discloses an optical element having a refractive lens array and a diffuser, both positioned on the same side of the optical element. A method of manufacturing such an optical element is also described herein.
1 . An optical element comprising a micro lens array of lenslets and a randomizing function wherein both the micro lens array of lenslets and the randomizing function reside on the same surface of the optical element; wherein the micro lens array comprises identical lenslets arrayed in both an X and a Y direction; and wherein the randomizing function is an overlaid diffuser.
2 . The optical element of claim 1 wherein distances of lens neighbor centers or pitch are identical in the X direction.
3 . The optical element of claim 1 wherein distances of lens neighbor centers or pitch are identical in the Y direction.
4 . The optical element of claim 1 wherein the optical element comprises a substrate comprising one or more layers comprising a plastic, a metal, a silicon wafer, or a glass plate.
5 . The optical element of claim 1 wherein the metal substrate or reflective optical coating on a metal, a plastic, a silicon wafer, or a glass plate makes the diffusing element a reflective diffuser.
6 . The optical element of claim 1 wherein a diffusion angle of the diffuser exceeds an order angle.
7 . The optical element of claim 1 wherein the size of a lenslet ranges from about 1 micron to about 1 mm.
8 . The optical element of claim 1 wherein the size of the micro array has an upper limit of about 500 mm by 300 mm or by tooling surface.
9 . The optical element of claim 1 wherein a surface profile of the lenslet is functionally refractive, diffractive, transmissive or reflective.
10 . The optical element of claim 1 wherein an individual lenslet sag ranges from about 1 micron to about 100 micron.
11 . The optical element of claim 10 wherein the lenslet sag is spherical, parabolic, hyperbolic, ellipse, aspheric or biconic.
12 . The optical element of claim 1 wherein the diffuser has a Gaussian function wherein distribution comprises 30 degrees full width half maximum or less.
13 . The optical element of claim 1 wherein distribution comprises flat top, deterministic, super gaussian, line generator, batwing or asymmetric to achieve very high uniformity of light.
14 . The optical element of claim 12 wherein the fullwidth at half maximum of the diffuser is greater than angular spacing of diffractive orders.
15 . The optical element of claim 12 comprising a flat top diffuser with rectangular, square, elliptical, circular, hexagonal, and and/or other geometric shapes.
16 . The optical element of claim 1 wherein the micro lens array is a lenticular lens array or an anamorphic lens array.
17 . The optical element of claim 1 wherein the diffuser comprises a diffusing angle ranging from 5° to 80°.
18 . An optical element comprising a refractive lens array and a diffuser wherein light utilization is maximized by directing light where needed and where light uniformity is increased by eliminating hot spots.
19 . The optical element of claim 1 comprising convolution with a light shaping diffuser pattern.
20 . The optical element of claim 1 wherein the micro lens array comprises convolving a comb function with a Gaussian function in angular space.
21 . The optical element of claim 1 further comprising a coherent or incoherent light source whose emitted light is diffused, shaped, and customized by application of the optical element.