US20200312914A1

US20200312914A1 - Optical devices with light collection elements formed in pixels

Info

Publication number: US20200312914A1
Application number: US16/371,634
Authority: US
Inventors: Zong-Ru Tu
Original assignee: VisEra Technologies Co Ltd
Current assignee: VisEra Technologies Co Ltd
Priority date: 2019-04-01
Filing date: 2019-04-01
Publication date: 2020-10-01
Anticipated expiration: 2039-04-01
Also published as: CN111769136A; CN111769136B; US10777609B1; JP2020170142A; JP6889761B2; TW202037934A; TWI706167B

Abstract

An optical device is provided. The optical device includes a central region having a plurality of central pixels, a first region having a plurality of first pixels, a second region having a plurality of second pixels, an organic layer formed in the central region, the first region and the second region, a light collection layer surrounded by the organic layer formed in the first region and the second region, a first light collection element of the light collection layer formed in the first pixel, and a second light collection element of the light collection layer formed in the second pixel. The central region, the first region and the second region are spaced from each other along an arrangement direction, and the first region is closer to the central region than the second region. The first light collection element is different from the second light collection element.

Description

BACKGROUND OF THE INVENTION

Field of the Invention

The invention relates to an optical device, and more particularly to an optical device with light collection elements of different dimensions or positions formed above color filters.

Description of the Related Art

In an optical device with a composite metal grid (CMG)-type structure, a microlens is required above the color filters. In an optical device with a wave guide color filter (WGCF)-type structure, a low-refractive-index material surrounding the color filters is used instead of a microlens to form a wave guide structure.
However, in an optical device with a wave guide color filter (WGCF)-type structure, due to the absorption of oblique light by metal grids, the quantum effect (QE) of the current pixel drops, especially for pixels located in the peripheral region of the substrate.
Therefore, development of an optical device with a wave guide color filter (WGCF)-type structure capable of improving the QE spectrum is desirable.

BRIEF SUMMARY OF THE INVENTION

In accordance with one embodiment of the invention, an optical device is provided. The optical device includes a central region having a plurality of central pixels, a first region having a plurality of first pixels, a second region having a plurality of second pixels, an organic layer formed in the central region, the first region and the second region, a light collection layer surrounded by the organic layer formed in the first region and the second region, a first light collection element of the light collection layer formed in the first pixel, and a second light collection element of the light collection layer formed in the second pixel. The central region, the first region and the second region are spaced from each other along an arrangement direction. The first region is closer to the central region than the second region. The first light collection element is different from the second light collection element.
In some embodiments, there is a first distance between a center of the first pixel and a center of the first light collection element. There is a second distance between a center of the second pixel and a center of the second light collection element. In some embodiments, the second distance is greater than the first distance. The center of the first light collection element departs from the center of the first pixel along a direction opposite to the arrangement direction of the central region, the first region and the second region. The center of the second light collection element departs from the center of the second pixel along the direction opposite to the arrangement direction of the central region, the first region and the second region.
In some embodiments, the first distance is the same as the second distance. In some embodiments, the second light collection element has a width which is greater than that of the first light collection element. In some embodiments, the width of the first light collection element is greater than zero. The width of the second light collection element is less than a width of the second pixel. In some embodiments, the second light collection element has an upper surface area which is greater than that of the first light collection element. In some embodiments, the second light collection element has a thickness which is greater than that of the first light collection element. In some embodiments, the thickness of the second light collection element is greater than that of the organic layer. In some embodiments, the first light collection element and the second light collection element are further covered by the organic layer. In some embodiments, a part of the second light collection element extends further into a color filter underneath the second light collection element. In some embodiments, the part of the second light collection element that extends into the color filter has a thickness that is less than one third of that of the color filter.
In some embodiments, the second light collection element has a width which is greater than that of the first light collection element. The second light collection element has a thickness which is greater than that of the first light collection element. In some embodiments, the second light collection element extends further over a patterned organic layer surrounding a color filter underneath the second light collection element. In some embodiments, the patterned organic layer has a refractive index which is in a range from about 1.2 to about 1.45.
In some embodiments, the first light collection element and the second light collection element have a refractive index which is greater than those of color filters respectively underneath the first light collection element and the second light collection element. In some embodiments, the first light collection element and the second light collection element have a refractive index which is in a range from about 1.6 to about 1.9. In some embodiments, the optical device further includes an anti-reflection layer formed on the organic layer, the first light collection element and the second light collection element. In some embodiments, the first light collection element and the second light collection element have a refractive index which is greater than that of the anti-reflection layer.
In the present invention, high-refractive-index (n=1.6-1.9) light collection elements with specific dimensions or positions are disposed above color filters. For the dimension requirement, the width (or thickness) of the light collection element disposed in the pixel far from the central pixel is greater than that of the light collection element disposed in the pixel adjacent to the central pixel. For the position requirement, the distance between the central point of the pixel and the central point of the light collection element (i.e. the departure distance of the light collection element from the central point of the pixel) in the pixel far from the central pixel is greater than that between the central point of the pixel and the central point of the light collection element in the pixel adjacent to the central pixel. Specifically, the departure direction of the light collection elements is opposite to the pixel-arrangement direction. Also, the departure direction of the light collection elements in the pixels is correspondingly altered in accordance with various pixel-arrangement directions. In addition, the refractive index of the light collection element is higher than that of adjacent materials. By disposing the specific light collection element, QE peaks of color filters are thus significantly improved, especially for pixels located in the peripheral region of the substrate.
A detailed description is given in the following embodiments with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:

FIG. 1 is a top view of pixel arrangement of an optical device in accordance with one embodiment of the invention;

FIG. 2 is a top view of the pixel structures of an optical device in accordance with one embodiment of the invention;

FIG. 3 is a cross-sectional view of the pixel structures of an optical device in accordance with one embodiment of the invention;

FIG. 4 is a top view of the pixel structures of an optical device in accordance with one embodiment of the invention;

FIG. 5 is a cross-sectional view of the pixel structures of an optical device in accordance with one embodiment of the invention;

FIG. 6 is a top view of the pixel structures of an optical device in accordance with one embodiment of the invention;

FIG. 7 is a cross-sectional view of the pixel structures of an optical device in accordance with one embodiment of the invention;

FIG. 8 is a top view of the pixel structures of an optical device in accordance with one embodiment of the invention;

FIG. 9 is a cross-sectional view of the pixel structures of an optical device in accordance with one embodiment of the invention;

FIG. 10 is a top view of the pixel structures of an optical device in accordance with one embodiment of the invention;

FIG. 11 is a cross-sectional view of the pixel structures of an optical device in accordance with one embodiment of the invention; and

FIG. 12 shows a QE peak of an optical device in accordance with one embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.
Referring to FIGS. 1-3, in accordance with one embodiment of the invention, an optical device 10 is provided. FIG. 1 is a top view of pixel arrangement of the optical device 10. FIG. 2 is a top view of the pixel structures of the optical device 10. FIG. 3 is a cross-sectional view of the pixel structures of the optical device 10.
In FIGS. 1 and 2, the optical device 10 includes a substrate 12 which includes a central region 14, a first region 16, a second region 18 and a third region 20. The central region 14, the first region 16, the second region 18 and the third region 20 are spaced from each other. The first region 16 is closer to the central region 14 than the second region 18. The second region 18 is closer to the first region 16 than the third region 20. The central region 14 has a plurality of central pixels, for example 14 a, 14 b, 14 c and 14 d. The first region 16 has a plurality of first pixels, for example 16 a, 16 b, 16 c and 16 d. The second region 18 has a plurality of second pixels, for example 18 a, 18 b, 18 c and 18 d. The third region 20 has a plurality of third pixels, for example 20 a, 20 b, 20 c and 20 d. The central pixels (ex. 14 a, 14 b, 14 c and 14 d) in the central region 14, the first pixels (ex. 16 a, 16 b, 16 c and 16 d) in the first region 16, the second pixels (ex. 18 a, 18 b, 18 c and 18 d) in the second region 18, and the third pixels (ex. 20 a, 20 b, 20 c and 20 d) in the third region 20 are arranged along a pixel-arrangement direction that is a direction from a center 12 a towards an edge 12 b of the substrate 12, for example, various pixel-arrangement directions (22 a, 22 b, 22 c, 22 d, 22 e, 22 f, 22 g and 22 h), as shown in FIG. 1. The pixel-arrangement direction 22 a represents the direction in which the pixels are arranged diagonally from the center to the bottom left of the substrate 12. The pixel-arrangement direction 22 b represents the direction in which the pixels are arranged horizontally (along x-axis) from the center to the left of the substrate 12. The pixel-arrangement direction 22 c represents the direction in which the pixels are arranged diagonally from the center to the top left of the substrate 12. The pixel-arrangement direction 22 d represents the direction in which the pixels are arranged perpendicularly (along y-axis) from the center to the top of the substrate 12. The pixel-arrangement direction 22 e represents the direction in which the pixels are arranged diagonally from the center to the top right of the substrate 12. The pixel-arrangement direction 22 f represents the direction in which the pixels are arranged horizontally (along x-axis) from the center to the right of the substrate 12. The pixel-arrangement direction 22 g represents the direction in which the pixels are arranged diagonally from the center to the bottom right of the substrate 12. The pixel-arrangement direction 22 h represents the direction in which the pixels are arranged perpendicularly (along y-axis) from the center to the bottom of the substrate 12. Here, the arrangement of the central pixels (ex. 14 a, 14 b, 14 c and 14 d), the first pixels (ex. 16 a, 16 b, 16 c and 16 d), the second pixels (ex. 18 a, 18 b, 18 c and 18 d), and the third pixels (ex. 20 a, 20 b, 20 c and 20 d) along the pixel-arrangement direction 22 a is exemplary.
In FIG. 2, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a include green (G) color filters 22. The central pixel 14 b, the first pixel 16 b, the second pixel 18 b and the third pixel 20 b include red (R) color filters 24. The central pixel 14 c, the first pixel 16 c, the second pixel 18 c and the third pixel 20 c include blue (B) color filters 26. The central pixel 14 d, the first pixel 16 d, the second pixel 18 d and the third pixel 20 d include green (G) color filters 22. In some embodiments, other arrangements of the R/G/B color filters (22, 24 and 26) in the pixels are also suitable in the present invention. Here, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a are exemplary for demonstrating various pixel structures thereamong.
Referring to FIGS. 2 and 3, the central pixel 14 a includes a plurality of metal grids 28, a patterned first organic layer 30, a color filter 32, and a second organic layer 34. The metal grids 28 are formed on the substrate 12. The patterned first organic layer 30 is formed on the metal grids 28. The color filter 32 is surrounded by the patterned first organic layer 30. The second organic layer 34 is formed on the patterned first organic layer 30 and the color filter 32. Each of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a includes a plurality of metal grids 28, a patterned first organic layer 30, a color filter 32, a second organic layer 34, and a light collection element 36. The metal grids 28 are formed on the substrate 12. The patterned first organic layer 30 is formed on the metal grids 28. The color filter 32 is surrounded by the patterned first organic layer 30. The second organic layer 34 is formed on the patterned first organic layer 30 and the color filter 32. The light collection element 36 is surrounded by the second organic layer 34. Specifically, the refractive index of the light collection element 36 is greater than that of the second organic layer 34. Therefore, no light collection element is disposed in the central pixel 14 a. In addition, for the first pixel 16 a, the second pixel 18 a and the third pixel 20 a, a first distance “D1” between the central point “Ps” of the first pixel 16 a and the central point “P_L” of the light collection element 36 is defined. A second distance “D2” between the central point “Ps” of the second pixel 18 a and the central point “P_L” of the light collection element 36 is defined. A third distance “D3” between the central point “Ps” of the third pixel 20 a and the central point “P_L” of the light collection element 36 is defined.
In FIGS. 2 and 3, the first distance “D1”, the second distance “D2” and the third distance “D3” are different thereamong. Referring to FIG. 2, the central point “P_L” of the light collection element 36 in the first pixel 16 a departs from the central point “Ps” of the first pixel 16 a along a direction 42. The central point “P_L” of the light collection element 36 in the second pixel 18 a departs from the central point “Ps” of the second pixel 18 a along the direction 42. The central point “P_L” of the light collection element 36 in the third pixel 20 a departs from the central point “Ps” of the third pixel 20 a along the direction 42. Specifically, the departure direction 42 represents the direction in which the central points “P_L” of the light collection elements 36 depart diagonally from the central points “Ps” towards the top right of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively. Here, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a, and the third pixel 20 a are arranged along the pixel-arrangement direction 22 a (i.e. a direction that the pixels are arranged diagonally from the center to the bottom left of the substrate 12), as shown in FIG. 1. Therefore, the departure direction 42 of the light collection elements 36 is opposite to the pixel-arrangement direction 22 a.
The departure direction 42 of the light collection elements 36 correspondingly alters in accordance with various pixel-arrangement directions to ensure that the departure direction of the light collection element is opposite to the pixel-arrangement direction. In some embodiments, when the central pixel 14 a, the first pixel 16 a, the second pixel 18 a, and the third pixel 20 a are arranged along the pixel-arrangement direction 22 b (i.e. a direction in which the pixels are arranged horizontally (along x-axis) from the center to the left of the substrate 12), the central points “P_L” of the light collection elements 36 depart horizontally from the central points “Ps” towards the right of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively. In some embodiments, when the central pixel 14 a, the first pixel 16 a, the second pixel 18 a, and the third pixel 20 a are arranged along the pixel-arrangement direction 22 c (i.e. a direction in which the pixels are arranged diagonally from the center to the top left of the substrate 12), the central points “P_L” of the light collection elements 36 depart diagonally from the central points “Ps” towards the bottom right of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively. In some embodiments, when the central pixel 14 a, the first pixel 16 a, the second pixel 18 a, and the third pixel 20 a are arranged along the pixel-arrangement direction 22 d (i.e. a direction in which the pixels are arranged perpendicularly (along y-axis) from the center to the top of the substrate 12), the central points “P_L” of the light collection elements 36 depart perpendicularly from the central points “Ps” towards the bottom of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively. In some embodiments, when the central pixel 14 a, the first pixel 16 a, the second pixel 18 a, and the third pixel 20 a are arranged along the pixel-arrangement direction 22 e (i.e. a direction in which the pixels are arranged diagonally from the center to the top right of the substrate 12), the central points “P_L” of the light collection elements 36 depart diagonally from the central points “Ps” towards the bottom left of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively. In some embodiments, when the central pixel 14 a, the first pixel 16 a, the second pixel 18 a, and the third pixel 20 a are arranged along the pixel-arrangement direction 22 f (i.e. a direction in which the pixels are arranged horizontally (along x-axis) from the center to the right of the substrate 12), the central points “P_L” of the light collection elements 36 depart horizontally from the central points “Ps” towards the left of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively. In some embodiments, when the central pixel 14 a, the first pixel 16 a, the second pixel 18 a, and the third pixel 20 a are arranged along the pixel-arrangement direction 22 g (i.e. a direction in which the pixels are arranged diagonally from the center to the bottom right of the substrate 12), the central points “P_L” of the light collection elements 36 depart diagonally from the central points “Ps” towards the top left of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively. In some embodiments, when the central pixel 14 a, the first pixel 16 a, the second pixel 18 a, and the third pixel 20 a are arranged along the pixel-arrangement direction 22 h (i.e. a direction in which the pixels are arranged perpendicularly (along y-axis) from the center to the bottom of the substrate 12), the central points “P_L” of the light collection elements 36 depart perpendicularly from the central points “Ps” towards the top of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively.
In FIGS. 2 and 3, the third distance “D3” in the third pixel 20 a is greater than the second distance “D2” in the second pixel 18 a. The second distance “D2” in the second pixel 18 a is greater than the first distance “D1” in the first pixel 16 a. The first distance “D1” in the first pixel 16 a is greater than zero.
In some embodiments, the patterned first organic layer 30 has a refractive index which is in a range from about 1.2 to about 1.45. In some embodiments, the refractive index of the light collection element 36 is greater than that of the color filter 32. In some embodiments, the refractive index of the light collection element 36 is in a range from about 1.6 to about 1.9. In some embodiments, each of the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a further includes an oxide layer 38 which covers the metal grids 28. In some embodiments, each of the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a further includes an anti-reflection layer 40 formed on the second organic layer 34. In some embodiments, the refractive index of the light collection element 36 is greater than that of the anti-reflection layer 40.
Referring to FIGS. 1, 4 and 5, in accordance with another embodiment of the invention, an optical device 10 is provided. FIG. 4 is a top view of the pixel structures of the optical device 10. FIG. 5 is a cross-sectional view of the pixel structures of the optical device 10.
In FIG. 1, similarly, the arrangement of the central pixels (ex. 14 a, 14 b, 14 c and 14 d), the first pixels (ex. 16 a, 16 b, 16 c and 16 d), the second pixels (ex. 18 a, 18 b, 18 c and 18 d), and the third pixels (ex. 20 a, 20 b, 20 c and 20 d) along the pixel-arrangement direction 22 a is exemplary.
In FIG. 4, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a include green (G) color filters 22. The central pixel 14 b, the first pixel 16 b, the second pixel 18 b and the third pixel 20 b include red (R) color filters 24. The central pixel 14 c, the first pixel 16 c, the second pixel 18 c and the third pixel 20 c include blue (B) color filters 26. The central pixel 14 d, the first pixel 16 d, the second pixel 18 d and the third pixel 20 d include green (G) color filters 22. In some embodiments, other arrangements of the R/G/B color filters (22, 24 and 26) in the pixels are also suitable in the present invention. Here, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a are exemplary for demonstrating various pixel structures thereamong.
Referring to FIGS. 4 and 5, the central pixel 14 a includes a plurality of metal grids 28, a patterned first organic layer 30, a color filter 32, and a second organic layer 34. The metal grids 28 are formed on the substrate 12. The patterned first organic layer 30 is formed on the metal grids 28. The color filter 32 is surrounded by the patterned first organic layer 30. The second organic layer 34 is formed on the patterned first organic layer 30 and the color filter 32. Each of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a includes a plurality of metal grids 28, a patterned first organic layer 30, a color filter 32, a second organic layer 34, and a light collection element 36. The metal grids 28 are formed on the substrate 12. The patterned first organic layer 30 is formed on the metal grids 28. The color filter 32 is surrounded by the patterned first organic layer 30. The second organic layer 34 is formed on the patterned first organic layer 30 and the color filter 32. The light collection element 36 is surrounded by the second organic layer 34. Specifically, the refractive index of the light collection element 36 is greater than that of the second organic layer 34. Therefore, no light collection element is disposed in the central pixel 14 a. In addition, for the first pixel 16 a, the second pixel 18 a and the third pixel 20 a, a first distance between the central point “Ps” of the first pixel 16 a and the central point “P_L” of the light collection element 36 is defined. A second distance between the central point “Ps” of the second pixel 18 a and the central point “P_L” of the light collection element 36 is defined. A third distance between the central point “Ps” of the third pixel 20 a and the central point “P_L” of the light collection element 36 is defined.
In FIGS. 4 and 5, the first distance, the second distance and the third distance are zero. Referring to FIG. 4, the central point “P_L” of the light collection element 36 in the first pixel 16 a and the central point “Ps” of the first pixel 16 a overlap. The central point “P_L” of the light collection element 36 in the second pixel 18 a and the central point “Ps” of the second pixel 18 a overlap. The central point “P_L” of the light collection element 36 in the third pixel 20 a and the central point “Ps” of the third pixel 20 a overlap. That is, there is no departure of the central points “P_L” of the light collection elements 36 from the central points “Ps” of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respctively.
In FIGS. 4 and 5, for the first pixel 16 a, the second pixel 18 a and the third pixel 20 a, a first width “W1” of the light collection element 36 in the first pixel 16 a is defined. A second width “W2” of the light collection element 36 in the second pixel 18 a is defined. A third width “W3” of the light collection element 36 in the third pixel 20 a is defined. Specifically, the third width “W3” of the light collection element 36 in the third pixel 20 a is greater than the second width “W2” of the light collection element 36 in the second pixel 18 a. The second width “W2” of the light collection element 36 in the second pixel 18 a is greater than the first width “W1” of the light collection element 36 in the first pixel 16 a. In some embodiments, the first width “W1” of the light collection element 36 in the first pixel 16 a is greater than zero. The third width “W3” of the light collection element 36 in the third pixel 20 a is smaller than the width “W” of the third pixel 20 a. In addition, a first area “A1” of the light collection element 36 in the first pixel 16 a is defined. A second area “A2” of the light collection element 36 in the second pixel 18 a is defined. A third area “A3” of the light collection element 36 in the third pixel 20 a is defined. Similarly, the third area “A3” of the light collection element 36 in the third pixel 20 a is greater than the second area “A2” of the light collection element 36 of the second pixel 18 a. The second area “A2” of the light collection element 36 of the second pixel 18 a is greater than the first area “A1” of the light collection element 36 of the first pixel 16 a.
In some embodiments, the patterned first organic layer 30 has a refractive index which is in a range from about 1.2 to about 1.45. In some embodiments, the refractive index of the light collection element 36 is greater than that of the color filter 32. In some embodiments, the refractive index of the light collection element 36 is in a range from about 1.6 to about 1.9. In some embodiments, each of the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a further includes an oxide layer 38 which covers the metal grids 28. In some embodiments, each of the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a further includes an anti-reflection layer 40 formed on the second organic layer 34. In some embodiments, the refractive index of the light collection element 36 is greater than that of the anti-reflection layer 40.
Referring to FIGS. 1, 6 and 7, in accordance with another embodiment of the invention, an optical device 10 is provided. FIG. 6 is a top view of the pixel structures of the optical device 10. FIG. 7 is a cross-sectional view of the pixel structures of the optical device 10.
In FIG. 1, similarly, the arrangement of the central pixels (ex. 14 a, 14 b, 14 c and 14 d), the first pixels (ex. 16 a, 16 b, 16 c and 16 d), the second pixels (ex. 18 a, 18 b, 18 c and 18 d), and the third pixels (20 a, 20 b, 20 c and 20 c) along the pixel-arrangement direction 22 a is exemplary.
In FIG. 6, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a include green (G) color filters 22. The central pixel 14 b, the first pixel 16 b, the second pixel 18 b and the third pixel 20 b include red (R) color filters 24. The central pixel 14 c, the first pixel 16 c, the second pixel 18 c and the third pixel 20 c include blue (B) color filters 26. The central pixel 14 d, the first pixel 16 d, the second pixel 18 d and the third pixel 20 d include green (G) color filters 22. In some embodiments, other arrangements of the R/G/B color filters (22, 24 and 26) in the pixels are also suitable in the present invention. Here, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a are exemplary for demonstrating various subpixel structures thereamong.
Referring to FIGS. 6 and 7, the central pixel 14 a includes a plurality of metal grids 28, a patterned first organic layer 30, a color filter 32, and a second organic layer 34. The metal grids 28 are formed on the substrate 12. The patterned first organic layer 30 is formed on the metal grids 28. The color filter 32 is surrounded by the patterned first organic layer 30. The second organic layer 34 is formed on the patterned first organic layer 30 and the color filter 32. Each of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a includes a plurality of metal grids 28, a patterned first organic layer 30, a color filter 32, a second organic layer 34, and a light collection element 36. The metal grids 28 are formed on the substrate 12. The patterned first organic layer 30 is formed on the metal grids 28. The color filter 32 is surrounded by the patterned first organic layer 30. The second organic layer 34 is formed on the patterned first organic layer 30 and the color filter 32. The light collection element 36 is surrounded by the second organic layer 34. Specifically, the refractive index of the light collection element 36 is greater than that of the second organic layer 34. Therefore, no light collection element is disposed in the central pixel 14 a. In addition, for the first pixel 16 a, the second pixel 18 a and the third pixel 20 a, a first distance between the central point “Ps” of the first pixel 16 a and the central point “P_L” of the light collection element 36 is defined. A second distance between the central point “Ps” of the second pixel 18 a and the central point “P_L” of the light collection element 36 is defined. A third distance between the central point “Ps” of the third pixel 20 a and the central point “P_L” of the light collection element 36 is defined.
In FIGS. 6 and 7, the first distance, the second distance and the third distance are zero. Referring to FIG. 6, the central point “P_L” of the light collection element 36 in the first pixel 16 a and the central point “Ps” of the first pixel 16 a overlap. The central point “P_L” of the light collection element 36 in the second pixel 18 a and the central point “Ps” of the second pixel 18 a overlap. The central point “P_L” of the light collection element 36 in the third pixel 20 a and the central point “Ps” of the third pixel 20 a overlap. That is, there is no departure of the central points “P_L” of the light collection elements 36 from the central points “Ps” of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively.
In FIG. 7, for the first pixel 16 a, the second pixel 18 a and the third pixel 20 a, the first thickness “T1” of the light collection element 36 in the first pixel 16 a is defined. The second thickness “T2” of the light collection element 36 in the second pixel 18 a is defined. The third thickness “T3” of the light collection element 36 in the third pixel 20 a is defined. Specifically, the third thickness “T3” of the light collection element 36 in the third pixel 20 a is greater than the second thickness “T2” of the light collection element 36 in the second pixel 18 a. The second thickness “T2” of the light collection element 36 in the second pixel 18 a is greater than the first thickness “T1” of the light collection element 36 in the first pixel 16 a. In FIG. 7, the second thickness “T2” of the light collection element 36 in the second pixel 18 a is greater than the thickness “T_L” of the second organic layer 34. In some embodiments, the light collection elements 36 respectively in the first pixel 16 a, the second pixel 18 a and the third pixel 20 a are further covered by the second organic layer 34 (not shown).
In some embodiments, the patterned first organic layer 30 has a refractive index which is in a range from about 1.2 to about 1.45. In some embodiments, the refractive index of the light collection element 36 is greater than that of the color filter 32. In some embodiments, the refractive index of the light collection element 36 is in a range from about 1.6 to about 1.9. In some embodiments, each of the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a further includes an oxide layer 38 which covers the metal grids 28. In some embodiments, each of the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a further includes an anti-reflection layer 40 formed on the second organic layer 34. In some embodiments, the refractive index of the light collection element 36 is greater than that of the anti-reflection layer 40.
Referring to FIGS. 1, 8 and 9, in accordance with another embodiment of the invention, an optical device 10 is provided. FIG. 8 is a top view of the pixel structures of the optical device 10. FIG. 9 is a cross-sectional view of the pixel structures of the optical device 10.
In FIG. 1, similarly, the arrangement of the central pixels (ex. 14 a, 14 b, 14 c and 14 d), the first pixels (ex. 16 a, 16 b, 16 c and 16 d), the second pixels (ex. 18 a, 18 b, 18 c and 18 d), and the third pixels (ex. 20 a, 20 b, 20 c and 20 d) along the pixel-arrangement direction 22 a is exemplary.
In FIG. 8, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a include green (G) color filters 22. The central pixel 14 b, the first pixel 16 b, the second pixel 18 b and the third pixel 20 b include red (R) color filters 24. The central pixel 14 c, the first pixel 16 c, the second pixel 18 c and the third pixel 20 c include blue (B) color filters 26. The central pixel 14 d, the first pixel 16 d, the second pixel 18 d and the third pixel 20 d include green (G) color filters 22. In some embodiments, other arrangements of the R/G/B color filters (22, 24 and 26) in the pixels are also suitable in the present invention. Here, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a are exemplary for demonstrating various subpixel structures thereamong.
Referring to FIGS. 8 and 9, the central pixel 14 a includes a plurality of metal grids 28, a patterned first organic layer 30, a color filter 32, and a second organic layer 34. The metal grids 28 are formed on the substrate 12. The patterned first organic layer 30 is formed on the metal grids 28. The color filter 32 is surrounded by the patterned first organic layer 30. The second organic layer 34 is formed on the patterned first organic layer 30 and the color filter 32. Each of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a includes a plurality of metal grids 28, a patterned first organic layer 30, a color filter 32, a second organic layer 34, and a light collection element 36. The metal grids 28 are formed on the substrate 12. The patterned first organic layer 30 is formed on the metal grids 28. The color filter 32 is surrounded by the patterned first organic layer 30. The second organic layer 34 is formed on the patterned first organic layer 30 and the color filter 32. The light collection element 36 is surrounded by the second organic layer 34. Specifically, the refractive index of the light collection element 36 is greater than that of the second organic layer 34. Therefore, no light collection element is disposed in the central pixel 14 a. In addition, for the first pixel 16 a, the second pixel 18 a and the third pixel 20 a, a first distance between the central point “Ps” of the first pixel 16 a and the central point “P_L” of the light collection element 36 is defined. A second distance between the central point “Ps” of the second pixel 18 a and the central point “P_L” of the light collection element 36 is defined. A third distance between the central point “Ps” of the third pixel 20 a and the central point “P_L” of the light collection element 36 is defined.
In FIGS. 8 and 9, the first distance, the second distance and the third distance are zero. Referring to FIG. 8, the central point “P_L” of the light collection element 36 in the first pixel 16 a and the central point “Ps” of the first pixel 16 a overlap. The central point “P_L” of the light collection element 36 in the second pixel 18 a and the central point “Ps” of the second pixel 18 a overlap. The central point “P_L” of the light collection element 36 in the third pixel 20 a and the central point “Ps” of the third pixel 20 a overlap. That is, there is no departure of the central points “P_L” of the light collection elements 36 from the central points “Ps” of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively.
In FIG. 9, a part of the light collection element 36 in the second pixel 18 a extends further into the color filter 32. Also, a part of the light collection element 36 in the third pixel 20 a extends further into the color filter 32. For the first pixel 16 a, the second pixel 18 a and the third pixel 20 a, the first thickness “T1” of the light collection element 36 in the first pixel 16 a is defined. The second thickness “T2” of the light collection element 36 in the second pixel 18 a is defined. The third thickness “T3” of the light collection element 36 in the third pixel 20 a is defined. Specifically, the third thickness “T3” of the light collection element 36 in the third pixel 20 a is greater than the second thickness “T2” of the light collection element 36 in the second pixel 18 a. The second thickness “T2” of the light collection element 36 in the second pixel 18 a is greater than the first thickness “T1” of the light collection element 36 in the first pixel 16 a. In some embodiments, the thickness “T3 _L” of the part of the light collection element 36 that extends into the color filter 32 is less than one third of the thickness “T_CF” of the color filter 32.
In some embodiments, the patterned first organic layer 30 has a refractive index which is in a range from about 1.2 to about 1.45. In some embodiments, the refractive index of the light collection element 36 is greater than that of the color filter 32. In some embodiments, the refractive index of the light collection element 36 is in a range from about 1.6 to about 1.9. In some embodiments, each of the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a further includes an oxide layer 38 which covers the metal grids 28. In some embodiments, each of the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a further includes an anti-reflection layer 40 formed on the second organic layer 34. In some embodiments, the refractive index of the light collection element 36 is greater than that of the anti-reflection layer 40.
Referring to FIGS. 1, 10 and 11, in accordance with another embodiment of the invention, an optical device 10 is provided. FIG. 10 is a top view of the pixel structures of the optical device 10. FIG. 11 is a cross-sectional view of the pixel structures of the optical device 10.
In FIG. 1, similarly, the arrangement of the central pixels (ex. 14 a, 14 b, 14 c and 14 d), the first pixels (ex. 16 a, 16 b, 16 c and 16 d), the second pixels (ex. 18 a, 18 b, 18 c and 18 d), and the third pixels (ex. 20 a, 20 b, 20 c and 20 d) along the pixel-arrangement direction 22 a is exemplary.
In FIG. 10, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a include green (G) color filters 22. The central pixel 14 b, the first pixel 16 b, the second pixel 18 b and the third pixel 20 b include red (R) color filters 24. The central pixel 14 c, the first pixel 16 c, the second pixel 18 c and the third pixel 20 c include blue (B) color filters 26. The central pixel 14 d, the first pixel 16 d, the second pixel 18 d and the third pixel 20 d include green (G) color filters 22. In some embodiments, other arrangements of the R/G/B color filters (22, 24 and 26) in the pixels are also suitable in the present invention. Here, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a are exemplary for demonstrating various subpixel structures thereamong.
Referring to FIGS. 10 and 11, the central pixel 14 a includes a plurality of metal grids 28, a patterned first organic layer 30, a color filter 32, and a second organic layer 34. The metal grids 28 are formed on the substrate 12. The patterned first organic layer 30 is formed on the metal grids 28. The color filter 32 is surrounded by the patterned first organic layer 30. The second organic layer 34 is formed on the patterned first organic layer 30 and the color filter 32. Each of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a includes a plurality of metal grids 28, a patterned first organic layer 30, a color filter 32, a second organic layer 34, and a light collection element 36. The metal grids 28 are formed on the substrate 12. The patterned first organic layer 30 is formed on the metal grids 28. The color filter 32 is surrounded by the patterned first organic layer 30. The second organic layer 34 is formed on the patterned first organic layer 30 and the color filter 32. The light collection element 36 is surrounded by the second organic layer 34. Specifically, the refractive index of the light collection element 36 is greater than that of the second organic layer 34. Therefore, no light collection element is disposed in the central pixel 14 a. In addition, for the first pixel 16 a, the second pixel 18 a and the third pixel 20 a, a first distance “D1” between the central point “Ps” of the first pixel 16 a and the central point “P_L” of the light collection element 36 is defined. A second distance “D2” between the central point “Ps” of the second pixel 18 a and the central point “P_L” of the light collection element 36 is defined. A third distance “D3” between the central point “Ps” of the third pixel 20 a and the central point “P_L” of the light collection element 36 is defined.
In FIGS. 10 and 11, the first distance “D1”, the second distance “D2” and the third distance “D3” are different thereamong. Referring to FIG. 10, the central point “P_L” of the light collection element 36 in the first pixel 16 a departs from the central point “Ps” of the first pixel 16 a along a direction 42. The central point “P_L” of the light collection element 36 in the second pixel 18 a departs from the central point “Ps” of the second pixel 18 a along the direction 42. The central point “P_L” of the light collection element 36 in the third pixel 20 a departs from the central point “Ps” of the third pixel 20 a along the direction 42. Specifically, the departure direction 42 represents the direction in which the central points “P_L” of the light collection elements 36 depart diagonally from the central points “Ps” to the top right of the first pixel 16 a, the second pixel 18 a and the third pixel 20 a respectively. Here, the central pixel 14 a, the first pixel 16 a, the second pixel 18 a, and the third pixel 20 a are arranged along the pixel-arrangement direction 22 a (i.e. a direction that the pixels are arranged diagonally from the center to the bottom left of the substrate 12), as shown in FIG. 1. Therefore, the direction 42 is opposite to the pixel-arrangement direction 22 a. In FIGS. 10 and 11, the third distance “D3” in the third pixel 20 a is greater than the second distance “D2” in the second pixel 18 a. The second distance “D2” in the second pixel 18 a is greater than the first distance “D1” in the first pixel 16 a. The first distance “D1” in the first pixel 16 a is greater than zero.
In FIGS. 10 and 11, for the first pixel 16 a, the second pixel 18 a and the third pixel 20 a, a first width “W1” of the light collection element 36 in the first pixel 16 a is defined. A second width “W2” of the light collection element 36 in the second pixel 18 a is defined. A third width “W3” of the light collection element 36 in the third pixel 20 a is defined. Specifically, the third width “W3” of the light collection element 36 in the third pixel 20 a is greater than the second width “W2” of the light collection element 36 in the second pixel 18 a. The second width “W2” of the light collection element 36 in the second pixel 18 a is greater than the first width “W1” of the light collection element 36 in the first pixel 16 a. In some embodiments, the first width “W1” of the light collection element 36 in the first pixel 16 a is greater than zero. The third width “W3” of the light collection element 36 in the third pixel 20 a is smaller than the width “W” of the third pixel 20 a. The light collection element 36 in the third pixel 20 a extends further over the patterned first organic layer 30, as shown in FIG. 11. In addition, a first area “A1” of the light collection element 36 in the first pixel 16 a is defined. A second area “A2” of the light collection element 36 in the second pixel 18 a is defined. A third area “A3” of the light collection element 36 in the third pixel 20 a is defined. Similarly, the third area “A3” of the light collection element 36 in the third pixel 20 a is greater than the second area “A2” of the light collection element 36 in the second pixel 18 a. The second area “A2” of the light collection element 36 in the second pixel 18 a is greater than the first area “A1” of the light collection element 36 in the first pixel 16 a.
In FIG. 11, for the first pixel 16 a, the second pixel 18 a and the third pixel 20 a, the first thickness “T1” of the light collection element 36 in the first pixel 16 a is defined. The second thickness “T2” of the light collection element 36 in the second pixel 18 a is defined. The third thickness “T3” of the light collection element 36 in the third pixel 20 a is defined. Specifically, the third thickness “T3” of the light collection element 36 in the third pixel 20 a is greater than the second thickness “T2” of the light collection element 36 in the second pixel 18 a. The second thickness “T2” of the light collection element 36 in the second pixel 18 a is greater than the first thickness “T1” of the light collection element 36 in the first pixel 16 a. In FIG. 11, the second thickness “T2” of the light collection element 36 in the second pixel 18 a is greater than the thickness “T_L” of the second organic layer 34. In some embodiments, the light collection elements 36 respectively in the first pixel 16 a, the second pixel 18 a and the third pixel 20 a are further covered by the second organic layer 34 (not shown).
In some embodiments, the patterned first organic layer 30 has a refractive index which is in a range from about 1.2 to about 1.45. In some embodiments, the refractive index of the light collection element 36 is greater than that of the color filter 32. In some embodiments, the refractive index of the light collection element 36 is in a range from about 1.6 to about 1.9. In some embodiments, each of the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a further includes an oxide layer 38 which covers the metal grids 28. In some embodiments, each of the central pixel 14 a, the first pixel 16 a, the second pixel 18 a and the third pixel 20 a further includes an anti-reflection layer 40 formed on the second organic layer 34. In some embodiments, the refractive index of the light collection element 36 is greater than that of the anti-reflection layer 40.
In the present invention, high-refractive-index (n=1.6-1.9) light collection elements with specific dimensions or positions are disposed above color filters. For the dimension requirement, the width (or thickness) of the light collection element disposed in the pixel far from the central pixel is greater than that of the light collection element disposed in the pixel adjacent to the central pixel. For the position requirement, the distance between the central point of the pixel and the central point of the light collection element (i.e. the departure distance of the light collection element from the central point of the pixel) in the pixel far from the central pixel is greater than that between the central point of the pixel and the central point of the light collection element in the pixel adjacent to the central pixel. Specifically, the departure direction of the light collection elements is opposite to the pixel-arrangement direction. Also, the departure direction of the light collection elements in the pixels is correspondingly altered in accordance with various pixel-arrangement directions. In addition, the refractive index of the light collection element is higher than that of adjacent materials. By disposing the specific light collection element, QE peaks of color filters are thus significantly improved, especially for pixels located in the peripheral region of the substrate.

Example 1

QE Peak Improvement of the Optical Device
In this example, improvement of a QE peak, especially for pixels located in the peripheral region of the substrate, is acknowledged by disposing a light collection element (i.e. a high-refractive-index layer) with a specific dimension in an optical device. Referring to FIG. 12, the column “A” shows a QE peak (R/G/B) of a WGCF-type optical device without disposing a light collection element therein. The column “B” shows a QE peak (R/G/B) of a WGCF-type optical device with a light collection element having a width of 0.3 μm. The column “C” shows a QE peak (R/G/B) of a WGCF-type optical device with a light collection element having a width of 0.7 μm. The QE peak (column “C”) built by the WGCF-type optical device with the wider light collection layer shows that the QE peak of the optical device is a significant improvement of about 1.3% over column “B”, and about 2.0% over column “A”.
While the invention has been described by way of example and in terms of preferred embodiment, it should be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.

Claims

1. An optical device, comprising:

a central region having a plurality of central pixels;

a first region having a plurality of first pixels;

a second region having a plurality of second pixels, wherein the central region, the first region and the second region are spaced from each other along an arrangement direction, and the first region is closer to the central region than the second region;

an organic layer formed in the central region, the first region and the second region;

a light collection layer surrounded by the organic layer formed in the first region and the second region;

a first light collection element of the light collection layer formed in each of the plurality of first pixels; and

a second light collection element of the light collection layer formed in each of the plurality of second pixels,

wherein the first light collection element is different from the second light collection element.

2. (canceled)

3. The optical device as claimed in claim 1, wherein

there is a first distance between a center of the first pixel and a center of the first light collection element, and there is a second distance between a center of the second pixel and a center of the second light collection element, and

the second distance is greater than the first distance, the center of the first light collection element departs from the center of the first pixel along a direction opposite to the arrangement direction of the central region, the first region and the second region, and the center of the second light collection element departs from the center of the second pixel along the direction opposite to the arrangement direction of the central region, the first region and the second region.

4. The optical device as claimed in claim 1, wherein

the first distance is the same as the second distance.

5. The optical device as claimed in claim 4, wherein the second light collection element has a width which is greater than that of the first light collection element.

6. The optical device as claimed in claim 5, wherein the width of the first light collection element is greater than zero, and the width of the second light collection element is less than a width of the second pixel.

7. The optical device as claimed in claim 4, wherein the second light collection element has an upper surface area which is greater than that of the first light collection element.

8. The optical device as claimed in claim 4, wherein the second light collection element has a thickness which is greater than that of the first light collection element.

9. The optical device as claimed in claim 8, wherein the thickness of the second light collection element is greater than that of the organic layer.

10. The optical device as claimed in claim 9, wherein the first light collection element and the second light collection element are further covered by the organic layer.

11. The optical device as claimed in claim 4, wherein a part of the second light collection element extends further into a color filter underneath the second light collection element.

12. The optical device as claimed in claim 11, wherein the part of the second light collection element that extends into the color filter has a thickness that is less than one third of that of the color filter.

13. The optical device as claimed in claim 3, wherein the second light collection element has a width which is greater than that of the first light collection element, and the second light collection element has a thickness which is greater than that of the first light collection element.

14. The optical device as claimed in claim 13, wherein the second light collection element extends further over a patterned organic layer surrounding a color filter underneath the second light collection element.

15. The optical device as claimed in claim 14, wherein the patterned organic layer has a refractive index which is in a range from about 1.2 to about 1.45.

16. The optical device as claimed in claim 1, wherein the first light collection element and the second light collection element have a refractive index which is greater than those of color filters respectively underneath the first light collection element and the second light collection element.

17. The optical device as claimed in claim 1, wherein the first light collection element and the second light collection element have a refractive index which is in a range from about 1.6 to about 1.9.

18. The optical device as claimed in claim 1, further comprising an anti-reflection layer formed on the organic layer, the first light collection element and the second light collection element.

19. The optical device as claimed in claim 18, wherein the first light collection element and the second light collection element have a refractive index which is greater than that of the anti-reflection layer.