Multiple microlens system for image sensors or display units

Abstract

An imager or display system with multiple lenses, which are formed, patterned and shaped over one or more pixels in an imager or display array. The multiple lenses provide for an improved concentration of light being refracted onto a photosensitive area or light diffused from a display pixel.

What is claimed as new and desired to be protected by Letters Patent of the United States is:  
     
         1 . A light detecting system comprising: 
 a photosensitive region; and    a lens structure for focusing light onto said photosensitive region, said lens structure comprising a first lens region and a second lens region, said first and second lens regions having different optical properties.    
     
     
         2 . A light detecting system of  claim 1 , comprising a plurality of said lens structures and a plurality of said photosensitive regions, wherein each said lens structure is respectively provided over each of said plurality of said photosensitive regions.  
     
     
         3 . A light detecting system as in  claim 2 , wherein said second lens region of each of said lens structures is noncontiguous with said second lens regions of other lens structures.  
     
     
         4 . A light detecting system as in  claim 2 , wherein said first and second lens region is noncontiguous with other first and second lens regions in other said lens structures.  
     
     
         5 . A light detecting system as in  claim 1 , wherein said first lens region is formed over said second lens region.  
     
     
         6 . A light detecting system as in  claim 1 , wherein said first lens region has a circular shape and is formed over said second lens region.  
     
     
         7 . A light detecting system as in  claim 6  further comprising a plurality of said photosensitive regions arranged in an array, each photosensitive region having an associated lens structure.  
     
     
         8 . A light detecting system as in  claim 1 , wherein said first lens region is formed over said second lens region and is aspherically shaped.  
     
     
         9 . A light detecting system as in  claim 1 , wherein said lens structure further comprises a third lens region.  
     
     
         10 . A light detecting system of  claim 9  further comprising a plurality of said photosensitive regions and a plurality of said lens structures, wherein each said lens structure is patterned and formed over a respective one of said plurality of photosensitive regions.  
     
     
         11 . A light detecting system as in  claim 9 , wherein said third lens region is formed over said first lens region.  
     
     
         12 . A light detecting system as in  claim 9 , wherein said third lens region has a circular shape and is formed over said first lens region.  
     
     
         13 . A light detecting system as in  claim 9 , wherein said third lens region is formed over said first lens region and is aspherically shaped.  
     
     
         14 . A light detecting system as in  claim 9 , wherein said first, second and third lens regions have different refraction indexes.  
     
     
         15 . A light detecting system as in  claim 1 , wherein said first and second lens regions have different refraction indexes.  
     
     
         16 . A light detecting system as in  claim 1 , wherein said photosensitive region is a photodiode.  
     
     
         17 . A light detecting system as in  claim 1 , wherein said second lens region refracts a portion of the light refracted by said first lens region.  
     
     
         18 . A light detecting system as in  claim 1 , wherein said first lens is formed in contact with said second lens region.  
     
     
         19 . A light detecting system as in  claim 1 , wherein said first lens region has a greater diameter than said second lens region.  
     
     
         20 . A light detecting system as in  claim 1 , wherein said first lens region is formed and patterned over a larger portion of said photosensitive region than said second lens region.  
     
     
         21 . A light detecting system as in  claim 1 , wherein one of said first and second lens regions refracts a portion of incident light that is not incident to the other of said first and second lens region.  
     
     
         22 . A light detecting system as in  claim 1 , wherein said first and second lens regions are formed of respective first and second materials.  
     
     
         23 . A light detecting system as in  claim 1 , wherein said first and second lens regions are formed of the same material but have different geometric shapes.  
     
     
         24 . A light detecting system as in  claim 1 , wherein said first and second lens regions have a respective first and second optical focus for incident light.  
     
     
         25 . A light detecting system as in  claim 1 , wherein at least one of said first and second lens regions is substantially aspherically shaped.  
     
     
         26 . A light detecting system as in  claim 1 , wherein at least one of said first and second lens regions is substantially circularly shaped.  
     
     
         27 . A light detecting system as in  claim 1 , wherein at least one of said first and second lens regions is substantially lenticularly shaped.  
     
     
         28 . A light detecting system as in  claim 1 , wherein at least one of said first and second lens regions is substantially ovoid shaped.  
     
     
         29 . A light detecting system as in  claim 1 , wherein at least one of said first and second lens regions is substantially rectangularly shaped.  
     
     
         30 . A light detecting system as in  claim 1 , wherein at least one of said first and second lens regions is substantially hexagonally shaped.  
     
     
         31 . A light detecting system as in  claim 1 , wherein said first lens region is formed above and in direct contact with a portion of said second lens regions, and wherein said second lens region has a ring shaped light refracting area.  
     
     
         32 . A light detecting system as in  claim 1 , wherein a refractive index of said first lens region is greater than a refractive index of said second lens region.  
     
     
         33 . A light detecting system as in  claim 1 , wherein said photosensitive region is part of a CMOS imager.  
     
     
         34 . A light detecting system as in  claim 1 , wherein said photosensitive region is part of a CCD imager.  
     
     
         35 . An imaging device comprising: 
 an imaging array comprising a plurality of photosensitive regions; and    a plurality of lens structures provided on said imaging array over respective ones of said photosensitive region, more than one lens structure comprising a plurality of microlenses, at least one of said microlenses comprises a plurality of lens regions, at least two of said lens regions having a different refractive property.    
     
     
         36 . An imaging device as in  claim 35 , wherein at least two lens regions have a circular shape.  
     
     
         37 . An imaging device as in  claim 36 , wherein each topmost lens region is not in contact with other topmost lens regions.  
     
     
         38 . An imaging device as in  claim 35 , wherein at least two of said plurality of lens regions are aspherically shaped.  
     
     
         39 . An imaging device as in  claim 35 , wherein said photosensitive regions comprise a photodiode.  
     
     
         40 . An imaging device as in  claim 35 , wherein at least one lens region refracts a portion of the light refracted by at least one other lens region.  
     
     
         41 . An imaging device as in  claim 35 , wherein at least one lens region is formed in contact with another lens region.  
     
     
         42 . An imaging device as in  claim 35 , wherein each of said lens structures is noncontiguous with other of said lens structures.  
     
     
         43 . An imaging device as in  claim 42 , wherein one of said plurality of lens regions has a greater diameter than another associated lens region.  
     
     
         44 . An imaging device as in  claim 35 , wherein an upper lens region of said plurality of lens regions in a lens structure is noncontiguous with another upper lens region in at least one other lens structure.  
     
     
         45 . An imaging device as in  claim 35 , wherein one of said plurality of said lens regions is formed and patterned over a larger portion of said photosensitive region than another lens region in the same lens structure.  
     
     
         46 . An imaging device as in  claim 35 , wherein one of said plurality of lens regions refracts a portion of incident light that is not incident to another of said plurality of lens regions within the same lens structure.  
     
     
         47 . An imaging device as in  claim 35 , wherein said plurality of lens regions are formed of more than one material.  
     
     
         48 . An imaging device as in  claim 35 , wherein said plurality of lens regions are formed of the same material, but have at least one different geometric shape.  
     
     
         49 . An imaging device as in  claim 35 , wherein each of said plurality of lens regions has a first and second optical focus for incident light.  
     
     
         50 . An imaging device as in  claim 35 , wherein one of said plurality of lens regions is formed above and in direct contact with a portion of another lens region.  
     
     
         51 . An imaging device as in  claim 35 , wherein one of said plurality of lens regions has a ring shaped light refracting area.  
     
     
         52 . An imaging device as in  claim 35 , wherein said photosensitive regions are part of a CMOS imager.  
     
     
         53 . An imaging device as in  claim 35 , wherein said photosensitive regions are part of a CCD imager.  
     
     
         54 . An imaging device as in  claim 35 , wherein one of said plurality of lens regions within a same lens structure is formed above and in direct contact with another one of said plurality of lens regions and with a different diameter.  
     
     
         55 . An imaging device as in  claim 54 , wherein at least one of said lens plurality of lens regions within a same lens structure comprises a ring shaped light condensing region.  
     
     
         56 . An image processing system comprising: 
 a processor coupled to a memory device via a bus; and    an imaging device coupled to said bus, said device comprising: 
 an imaging array containing a plurality of photosensitive regions; and  
 a plurality of lens structures provided on said imaging array over respective ones of said photosensitive region, at least one of said lens structures comprising a plurality of microlenses, at least some of said microlenses each comprising a plurality of lens regions, at least two of each lens regions having a different refractive property.  
   
     
     
         57 . An image processing system as in  claim 56 , wherein said plurality of lens regions have a circular shape.  
     
     
         58 . An image processing system as in  claim 56 , wherein more than one of said plurality of lens structures are aspherically shaped.  
     
     
         59 . An image processing system as in  claim 56 , wherein a topmost lens region of at least one of said lens structures is noncontiguous with a topmost lens region of another said lens structure.  
     
     
         60 . An image processing system as in  claim 56 , wherein one of said plurality of lens regions refracts a portion of incident light that is not incident to another of said plurality of lens regions.  
     
     
         61 . An image processing system as in  claim 56 , wherein said plurality of lens regions are formed of more than one material.  
     
     
         62 . An image processing system as in  claim 56 , wherein one of said plurality of lens region comprises a ring shaped light refracting area.  
     
     
         63 . A CMOS imager comprising: 
 a photosensitive region; and    a lens structure located vertically above the photosensitive region, wherein the lens structure comprises a first and second materials having refractive indexes of N1 and N2, respectively, where N1>N2.    
     
     
         64 . A CMOS imager as in  claim 63 , further comprising a plurality of said lens structures and a plurality of said photosensitive regions, wherein each said lens structure is respectively provided over said plurality of said photosensitive regions.  
     
     
         65 . A CMOS imager as in  claim 63 , wherein said first material is formed over said second material.  
     
     
         66 . A CMOS imager as in  claim 64 , wherein said first material has a circular shape and is formed over said second material.  
     
     
         67 . A display system comprising 
 a plurality of display structures; and    a lens structure formed above at least one of said plurality of display structures, said lens structure being adapted to redirect light from said display structure outwardly of said lens structure, said lens structure including a first lens region and a second lens region, said first and second lens regions having different optical properties from one another.    
     
     
         68 . A display system as in  claim 67  wherein one said lens structure is disposed above each of said plurality of display structures.  
     
     
         69 . A display system as in  claim 67  wherein a plurality of said lens structures is disposed above at least some of said plurality of display structures.  
     
     
         70 . A display system as in  claim 67 , comprising a first plurality of said lens structures and a second plurality of said display structures, wherein each lens structure of said first plurality is disposed over a display structure of said second plurality respectively.  
     
     
         71 . A display system as in  claim 70 , wherein said second lens region of each of said lens structures is noncontiguous with said second lens regions of other lens structures.  
     
     
         72 . A display system as in  claim 70 , wherein said first and second lens region is noncontiguous with other first and second lens regions in other said lens structures.  
     
     
         73 . A display system as in  claim 67 , wherein said first lens region is formed over said second lens region.  
     
     
         74 . A display system as in  claim 67 , wherein said first lens region has a circular shape and is formed over said second lens region.  
     
     
         75 . A display system as in  claim 74  wherein said plurality of display structures is arranged in an array, each display structure of said plurality having an associated lens structure.  
     
     
         76 . A display system as in  claim 67 , wherein said first lens region is disposed above said second lens region and is aspherically shaped.  
     
     
         77 . A display system as in  claim 67 , wherein said lens structure further comprises a third lens region.  
     
     
         78 . A display system as in  claim 77 , wherein each said lens structure is patterned and formed over a respective one of said plurality of display structures.  
     
     
         79 . A display system as in  claim 77 , wherein said third lens region is disposed above said first lens region, wherein said second lens region is disposed between said first and said third lens regions.  
     
     
         80 . A display system as in  claim 77 , wherein said third lens region has a circular shape and is disposed above said first lens region.  
     
     
         81 . A display system as in  claim 77 , wherein said third lens region is disposed above said first lens region and is aspherically shaped.  
     
     
         82 . A display system as in  claim 77 , wherein said first, second and third lens regions have differing indices of refraction with respect to one another.  
     
     
         83 . A display system as in  claim 67 , wherein said first and second lens regions have different refraction indexes.  
     
     
         84 . A display system as in  claim 67 , wherein said display structure is a display pixel in an active matrix liquid crystal display.  
     
     
         85 . A display system as in  claim 67 , wherein said second lens region refracts a portion of the light refracted by said first lens region.  
     
     
         86 . A display system as in  claim 67 , wherein said first lens is formed in contact with said second lens region.  
     
     
         87 . A display system as in  claim 67 , wherein said first lens region has a greater diameter than said second lens region.  
     
     
         88 . A display system as in  claim 67 , wherein said first lens region is formed and patterned over a larger portion of said display structure than said second lens region.  
     
     
         89 . A display system as in  claim 67 , wherein one of said first and second lens regions refracts a portion of incident light that is not incident to the other of said first and second lens region.  
     
     
         90 . A display system as in  claim 67 , wherein said first and second lens regions are formed of respective first and second materials.  
     
     
         91 . A display system as in  claim 67 , wherein said first and second lens regions are formed of the same material but have different geometric shapes.  
     
     
         92 . A display system as in  claim 67 , wherein at least one of said first and second lens regions is substantially aspherically shaped.  
     
     
         93 . A display system as in  claim 67 , wherein at least one of said first and second lens regions is substantially circularly shaped.  
     
     
         94 . A display system as in  claim 67 , wherein at least one of said first and second lens regions is substantially lenticularly shaped.  
     
     
         95 . A display system as in  claim 67 , wherein at least one of said first and second lens regions is substantially ovoid shaped.  
     
     
         96 . A display system as in  claim 67 , wherein at least one of said first and second lens regions is substantially rectangularly shaped.  
     
     
         97 . A display system as in  claim 67 , wherein at least one of said first and second lens regions is substantially hexagonally shaped.  
     
     
         98 . A display system as in  claim 67 , wherein said first lens region is formed above and in direct contact with a portion of said second lens regions, and wherein said second lens region has a ring shaped light refracting area.  
     
     
         99 . A display system as in  claim 67 , wherein a first and second plurality of said lens structures are disposed above said plurality of display structures, said first plurality of said lens structures having said first lens regions with a first refractive index, said second plurality of said lens structures having said first lens regions with a second refractive index.  
     
     
         100 . A method of forming a lens structure for an imager, said method comprising: 
 forming a first plurality of light condensing regions having a first refractive index over a plurality of photosensitive regions; and    forming a second plurality of light condensing regions having a second refractive index over said first plurality of light condensing regions.    
     
     
         101 . A method as in  claim 100 , wherein a refraction index of said first plurality of light condensing regions is greater than a refraction index of said second plurality of light condensing regions.  
     
     
         102 . A method as in  claim 100  further comprising forming a plurality of third light condensing regions respectively above said second plurality of light condensing regions.  
     
     
         103 . A method as in  claim 100 , wherein each of said first and second plurality of light condensing regions are formed in a substantially circular shape over said photosensitive regions.  
     
     
         104 . A method as in  claim 100 , wherein said light condensing regions are formed in a semicircular shape over said photosensitive regions.  
     
     
         105 . A method as in  claim 100 , wherein said light condensing regions are formed in a rectangular shape over said photosensitive regions.  
     
     
         106 . A method as in  claim 100 , wherein said light condensing regions are formed in a hexagonal shape over said photosensitive regions.  
     
     
         107 . A method as in  claim 100 , wherein said light condensing regions are formed in a lenticular shape over said photosensitive regions.  
     
     
         108 . A method as in  claim 100 , wherein said light condensing regions are formed in an ovoid shape over said photosensitive regions.  
     
     
         109 . A method as in  claim 100 , wherein said forming steps include heat treatment.  
     
     
         110 . A method as in  claim 100 , wherein said forming steps include baking.  
     
     
         111 . A method of forming an imager structure comprising: 
 forming first and second groups of photosensitive regions on an imager substrate;    forming a first lens region with a first refractive property over each of said photosensitive regions of said first group;    forming a second lens region with a second refractive property over each of said first lens regions; and    forming at least one other lens region having a refractive property over each of said second photosensitive regions of said second group.    
     
     
         112 . A method as in  claim 111 , wherein said first lens regions refractive index is greater than said second lens regions refraction index.  
     
     
         113 . A method as in  claim 111 , wherein at least one of said first and second lens regions is formed in a circular shape over said photosensitive regions of said first group.  
     
     
         114 . A method as in  claim 111 , wherein said first and second lens regions are formed in a circular shape over said photosensitive regions of said first group.  
     
     
         115 . A method as in  claim 111 , wherein said first and second lens regions are formed in a semicircular shape over said photosensitive regions of said first group.  
     
     
         116 . A method as in  claim 111 , wherein said first and second lens regions are formed in a rectangular shape over said photosensitive regions of said first group.  
     
     
         117 . A method as in  claim 111 , wherein said first and second lens regions are formed in a hexagonal shape over said photosensitive regions of said first group.  
     
     
         118 . A method as in  claim 111 , wherein said first and second lens regions are formed in a lenticular shape over said photosensitive regions of said first group.  
     
     
         119 . A method as in  claim 111 , wherein said first and second lens regions are formed in an ovoid shape over said photosensitive regions of said first group.  
     
     
         120 . A method as in  claim 111 , wherein said forming includes heat treatment.