Microlens array with improved fill factor
First Claim
1. A microlens array for use in an imaging device comprising:
- an imaging array containing photosensitive elements;
a light condensing layer provided on said imaging array, said light condensing layer having a plurality of microlenses each corresponding to one or more pixels of said array, and wherein said microlenses have convex surfaces facing away from said imaging array; and
a transparent insulation layer for increasing the proportion of radiation incident on said photosensitive elements of said imaging array, said transparent insulation layer being formed on said light condensing layer by a low temperature process, and wherein said transparent insulation layer has convex surfaces facing away from said microlenses, and wherein said transparent insulation layer includes silicon insulator material.
2 Assignments
0 Petitions
Accused Products
Abstract
A microlens array for use in a solid-state imager having an improved fill factor. The microlens array includes a plurality of microlenses, each consisting of two layers: a lower refractive layer, and an upper insulation layer. The refractive layer is formed of transparent material with a suitable refractive index which may be optical thermoplastic, polyimide, thermoset resin, photosensitive gelatin, or radiation curable resin. The insulation layer is formed of transparent insulating material such as silicon oxide, silicon nitride, or silicon oxynitride. Due to the refraction of light through the insulation layer, more light at the pixel edges is captured by each microlens, thereby improving the fill factor of the microlens array. Also disclosed are methods for forming the microlens array.
-
Citations
59 Claims
-
1. A microlens array for use in an imaging device comprising:
-
an imaging array containing photosensitive elements;
a light condensing layer provided on said imaging array, said light condensing layer having a plurality of microlenses each corresponding to one or more pixels of said array, and wherein said microlenses have convex surfaces facing away from said imaging array; and
a transparent insulation layer for increasing the proportion of radiation incident on said photosensitive elements of said imaging array, said transparent insulation layer being formed on said light condensing layer by a low temperature process, and wherein said transparent insulation layer has convex surfaces facing away from said microlenses, and wherein said transparent insulation layer includes silicon insulator material. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22)
-
-
23. A microlens array for use in an imaging device comprising:
- an array of piano-convex microlenses for converging light onto photosensitive elements, said array of plano-convex microlenses comprising refractive portions having convex surfaces, and a transparent insulation layer for increasing the proportion of radiation incident on said photosensitive elements, said transparent insulation layer being located on said convex surfaces of said refractive portions, and wherein said transparent insulation layer is formed on said convex surfaces by a low temperature process, and wherein said transparent insulation layer has convex surfaces facing away from said refractive portions of said microlenses, and wherein said transparent insulation layer includes silicon insulator material.
- View Dependent Claims (24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43)
-
44. A solid-state imager comprising:
-
an array of pixel sensor cells formed at an upper surface of a substrate;
a protective layer formed over said array; and
an array of microlenses formed on said protective layer for converging light on said pixel sensor cells, each microlens comprising a transparent insulation layer formed over a refractive layer, and wherein said transparent insulation layer is formed on said microlenses by a low temperature process, and wherein said transparent insulation layer has curved surfaces, and wherein said refractive layer is located between pixel sensor cells and said transparent insulation layer, such that said light is incident on said curved surfaces of said transparent insulation layer, and wherein said microlenses are arranged such that said insulation layer captures light at the edges of said pixel sensor cells, and wherein said transparent insulation layer includes silicon insulator material. - View Dependent Claims (45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56)
-
-
57. An imager comprising:
-
an imaging array having a plurality of pixel sensor cells formed at an upper surface of a substrate and providing output data representing an image;
an array of microlenses formed on the imaging array, wherein each microlens has a transparent insulation layer vapor deposited by a low temperature process on a convex surface of a refractive layer, and wherein said transparent insulation layer includes silicon insulator material, and wherein said transparent insulation layer has a concave surface and a convex surface, with said concave surface of said transparent insulation layer being located between said convex surface of said refractive layer and said convex surface of said transparent insulation layer, such that said transparent insulation layer increases the proportion of radiation incident on said pixel sensor cells; and
a processor for receiving and processing data representing the image. - View Dependent Claims (58, 59)
-
Specification