WO2003044831A2 - System for diffracting radiation in a solid state image sensor - Google Patents

System for diffracting radiation in a solid state image sensor Download PDF

Info

Publication number
WO2003044831A2
WO2003044831A2 PCT/US2002/018586 US0218586W WO03044831A2 WO 2003044831 A2 WO2003044831 A2 WO 2003044831A2 US 0218586 W US0218586 W US 0218586W WO 03044831 A2 WO03044831 A2 WO 03044831A2
Authority
WO
WIPO (PCT)
Prior art keywords
pixel
radiation spectrum
relation
lens
aperture
Prior art date
Application number
PCT/US2002/018586
Other languages
French (fr)
Other versions
WO2003044831A3 (en
Inventor
Zhang Zhihong
Original Assignee
Conexant Systems, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Conexant Systems, Inc. filed Critical Conexant Systems, Inc.
Priority to AU2002364689A priority Critical patent/AU2002364689A1/en
Publication of WO2003044831A2 publication Critical patent/WO2003044831A2/en
Publication of WO2003044831A3 publication Critical patent/WO2003044831A3/en

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14601—Structural or functional details thereof
    • H01L27/14625—Optical elements or arrangements associated with the device
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/80—Camera processing pipelines; Components thereof
    • H04N23/84—Camera processing pipelines; Components thereof for processing colour signals

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Power Engineering (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Signal Processing (AREA)
  • Multimedia (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Solid State Image Pick-Up Elements (AREA)
  • Transforming Light Signals Into Electric Signals (AREA)
  • Investigating Materials By The Use Of Optical Means Adapted For Particular Applications (AREA)

Abstract

In a solid-state image sensor using a diffraction element to diffract the radiation onto a pixel. The resulting diffraction pattern has a high intensity area at which a majority of the radiation intensity of the entire diffraction pattern is concentrated. In one approach this high intensity area may be positioned to fall incident upon the detecting area of the pixel. The diffraction element may utilize either an aperture or a lens within an opaque element. An associated method for detecting radiation is also disclosed.

Description

PATENT
SNR Matter No. 9785980-0048
00CXT0209I
SYSTEM FOR DIFFRACTING RADIATION IN A SOLID STATE IMAGE
SENSOR
INVENTOR
Zhihong Zhang BACKGROUND OF THE INVENTION
1. Technical Field.
This invention relates to solid-state image sensors. In particular, the invention relates to a system and method for diffracting radiation in a solid-state image sensor so as to increase the intensity of the incident radiation. 2. Related Art.
Solid-state image sensors have broad applications in many areas including commercial, consumer, industrial, medical, defense and scientific fields. Solid-state image sensors convert a received image such as from an object into a signal indicative of the received image. Examples of solid-state image sensors include charge coupled devices (CCD), photodiode arrays, charge injection devices (CID), hybrid focal plane arrays and complementary metal oxide semiconductor (CMOS) imaging devices.
Solid-state image sensors are fabricated from semiconductor materials (such as silicon or gallium arsenide) and include imaging arrays of light detecting (i.e., photosensitive) elements (also known as photodetectors) interconnected to generate analog signals representative of an image illuminating the device. These imaging arrays are typically formed from rows and columns of photodetectors (such as photodiodes, photoconductors, photocapacitors or photogates), each of which generate photo-charges. The photo-charges are the result of photons striking the surface of the semiconductor material of the photodetector, which generate free l PATENT
SNR Matter No. 9785980-0048
00CXT0209I charge carriers (electron-hole pairs) in an amount linearly proportional to the incident photon radiation.
Each photodetector in the imaging array receives a portion of the light reflected from the object received at the solid-state image sensor. Each portion is called a picture element or "pixel." Each individual pixel provides an output signal corresponding to the radiation intensity falling upon its detecting area (also known as the photosensitive or detector area) defined by the physical dimensions of the photodetector. The photo-charges from each pixel are converted to a signal (charge signal) or an electrical potential representative of the energy level reflected from a respective portion of the object. The resulting signal or potential is read and processed by video processing circuitry to create an electrical representation of the image.
The detecting area of each pixel is typically smaller than the actual physical pixel dimensions because of manufacturing process constraints, the presence of other circuitry in the pixel area (such as the active elements in CMOS imager arrays) in addition to the photodetector and the proximity of adjacent pixels. The percentage ratio of the detector area to the pixel area is typically referred to as the optical "fill factor."
Typically, microlenses (also known as microlenticular arrays or lenslet arrays) increase the effective optical fill factor of a pixel by increasing (i.e., focusing) the amount of radiation that is incident upon the detecting area. The microlens covers an area larger than the detecting area, such that the radiation, which would normally fall outside the detecting area, is refracted by the microlens to the detecting area of the PATENT
SNR Matter No. 9785980-0048
00CXT0209I pixel. Microlenses are typically placed over every pixel in the pixel array, thus increasing the radiation intensity (i.e., increasing the fill factor) that is incident on every pixel.
As the pixel and microlens sizes decrease, the microlens becomes less
effective. Typically, microlenses under 5μm, the optical performance of the
microlens degrades and radiation incident upon the microlens is not refracted properly onto the detecting area of the pixel. Thus, a significant amount of the radiation intensity incident upon the pixel is not directed to the detecting area of the pixel. Therefore, there is a need for a system and method that focuses radiation onto the detecting area of a pixel for smaller pixel sizes such that a sufficient intensity of radiation falls incident upon the detecting area of the pixel so that the radiation is detected by the pixel.
SUMMARY
A number of technical advances are achieved in the art, by implementation of an arrangement of diffraction elements to diffract radiation onto the pixels in a solid- state image sensor. The resulting diffraction pattern has a high intensity area at which a majority of the radiation intensity of the entire diffraction pattern is concentrated. In one approach this high intensity area may be positioned to fall incident upon the detecting area of the pixel. The diffraction element may utilize either an aperture or a lens within an opaque element.
This invention includes a method for detecting radiation in an array of pixels. The method involves receiving radiation upon a diffraction element positioned over a first pixel and then diffracting that radiation onto the first pixel such that the PATENT
SNR Matter No. 9785980-0048
00CXT0209Ϊ diffraction pattern is formed incident upon the first pixel. Among other aspects, the radius of an aperture of the diffraction element is determined in relation to a detecting area of the first pixel and perhaps the distance from the pixel to the diffraction element. Other systems, methods, features and advantages of the invention will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims. BRIEF DESCRIPTION OF THE DRAWINGS
The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views. FIG. 1 is a top plan view of a solid-state image sensor with a plurality of pixels arranged in an array;
FIG 2 is a block diagram of one of the individual pixels from FIG. 1;
FIG. 3 is a perspective view of one example of the invention using a diffraction element having an aperture; FIG. 4 is a perspective view of another example of the invention using a diffraction element having a lens;
FIG. 5 is a top view of one example of a Fraunhofer diffraction pattern created by either a circular aperture or lens; PATENT
SNR Matter No. 9785980-0048
00CXT0209I
FIG. 6 is an intensity profile of the Fraunhofer diffraction pattern from FIG. 5;
FIG. 7 is a perspective view of another example of a diffraction element;
FIG. 8 is a top plan view of one example of a Fraunhofer diffraction pattern created by a strip lens or aperture; and FIG. 9 is a front elevational cross sectional view of an example implementation of this invention where neighboring pixels are optically separated.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The solid-state image sensor of this invention includes a diffraction element that focuses the radiation onto the pixels and preferably upon their detecting areas. This invention may be utilized jn association with various types of solid-state image sensors (also referred to as "solid-state imagers," "imagers," or "image sensors'4), including but not limited to complementary metal oxide semiconductor (CMOS) imaging devices, charge couples devices (CCD), charge injection devices (CID), and metal oxide semiconductor (MOS) devices. As an example, the implementations of the invention are discussed in association with CMOS image sensors. However, it is appreciated by those skilled in the art that implementation may also utilize CCD, CID or MOS solid-state image sensors.
FIG. 1 shows a number of individual pixels arranged in an array 100 in order to detect radiation falling incident over a given area. Although each pixel in the array in FIG. 1 is shown as being square-shaped, each individual pixel may be fabricated with different shapes such as circular, rectangular, oval, pentagonal, or hexagonal. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
The pixels may utilize various types of photodetectors such as photodiodes, photoconductors, photocapacitors, or photogates. These photodetectors generate a charge or electrical potential (generically referred to as signals) dependent upon the wavelength of the incident radiation, the intensity of the incident radiation and the device characteristics of the photodetectors. Thus, the signals generated by the photodetectors are generally indicative of the intensity of the radiation that falls incident upon the detector.
In one approach, each individual pixel may measure only one portion of the radiation spectrum that falls incident upon the pixel and converts it into a measurable signal indicative of the intensity of the incident radiation. For instance, the pixel array 100 includes, among a plurality of other pixels, a first pixel 110, a second pixel 120, and third pixel 130. Each of these first, second and third pixels may be utilized to detect a different portion of the radiation spectrum. The portions of the radiation spectrum detected by the image sensor may include visible light range, infrared range, ultraviolet range, microwave range, x-ray range, and gamma radiation range. So, where the solid-state image sensor is designed to receive visible light, the first pixel 1 10 may be optimized to detect red light, the second pixel 120 may be optimized to detect green light, and the third pixel 130 may be optimized to detect blue light.
FIG. 2 is a simplified block diagram of first pixel 110 from the sensor array in FIG. 1. The first pixel 110 includes a detecting area 200 and a non-detecting area 202. The detecting area 200 is photosensitive including a photodetector such as a photodiode, a photoconductor, a photocapacitor, or a photogate. The non-detecting area 202 typically includes circuitry for converting a charge generated by the PATENT
SNR Matter No. 9785980-0048
00CXT0209I detecting area 200 into a measurable signal and for transferring that signal to video processing circuitry. The non-detecting area 202 is not photosensitive and radiation falling on the non-detecting area 202 of the pixel 1 10 is typically not detected. The relative sizes and configurations of the detecting area and the non-detecting area may be altered in various solid-state image sensor designs as is well known in the art.
FIG. 3 is a perspective view of the first pixel 1 10, a first filter 300 and a first diffraction element 302. Filters, such as first filter 300 are selected and typically positioned over an associated pixel, such as first pixel 1 10 to pass through the portion of the radiation spectrum sensed by its associated pixel while substantially obstructing other portions of the radiation spectrum. For example, if the first pixel 110 is intended to detect the intensity of blue light, first filter 300 is chosen to allow blue light to substantially pass through. As a result, the detecting area of the first pixel 110 will detect the intensity of blue light. Of course, other filters such as red filters, green filters and other filters for the invisible spectrum are known to those of ordinary skill in the art.
The first diffraction element 302 is positioned over the first pixel 110. In the example shown in FIG. 3, the first diffraction element 302 is also positioned over the first filter 300, such that radiation is first diffracted by the diffraction element 302 and then filtered. The first diffraction element 302 may be alternatively placed below the first filter 300. As would be understood by those of ordinary skill in the art having this specification before them, this invention does not require the utilization of any filter. The first diffraction element 302 diffracts the radiation incident upon the diffraction element 302 onto the first pixel 110. The diffracted radiation forms a PATENT
SNR Matter No. 9785980-0048
O0CXTO209I diffraction pattern on the pixel, which is detected by the first pixel 110 and converted into an electrical signal.
In the illustration of FIG. 3, the diffraction element 302 has an aperture 304 within an opaque portion 306. Typically, when radiation passes through an aperture, the image formed by the radiation has a diameter approximately equal to the diameter of the aperture. However, as the diameter of the aperture is decreased, the radiation is diffracted and the diameter of the diffracted image is larger than the diameter of the aperture. The diameter of the aperture 304 is preferably on the order of several micrometers such that the radiation that passes through the aperture 304 is diffracted, forming a diffraction pattern incident upon the first pixel 110.
Generally, the resulting diffraction pattern has a high intensity area at which a majority of the radiation intensity of the entire diffraction pattern is concentrated. Preferably, the aperture of the diffraction element 302 is positioned such that the high intensity area created by radiation being diffracted thereby falls incident upon the detecting area of the first pixel 1 10. Furthermore, the aperture 304 may also be situated within the diffraction element 302 such that the center of the aperture 304 is concentric with the center of the detecting area of the first pixel in order to increase the portion of the high intensity area that is incident upon the detecting area.
In another approach shown in FIG. 4, the diffraction element 400 includes a lens 402 situated within the opaque portion 404 of the diffraction element 400. As in the other approach, the diameter of the lens 402 may also be on the order of several micrometers in order to diffract radiation incident upon the diffraction element 400 onto the first pixel 110, thus forming a diffraction pattern incident upon the first pixel PATENT
SNR Matter No. 9785980-0048
0OCXT02O9I
110. Similarly, the diffraction element 400 is also positioned over a filter 406, such that radiation is first diffracted by the diffraction element 400 and then filtered by the filter 406. Also, as in the other approach, the lens 402 is also preferably situated within the diffraction element 400 such that the lens 402 is concentric with the center of the detecting area of the first pixel 1 10. It would be understood by one skilled in the art having the this specification before them that the type of lens or aperture utilized in this invention may be changed as long as the radiation incident upon the diffraction element is diffracted onto the pixel.
Generally, the solid-state image sensor is utilized in conjunction with a camera or other such image recording device. As such, radiation typically passes through a front camera lens (not shown) prior to reaching the diffraction element and pixel array 100, FIG. 1. Due to the presence of the camera lens, the radiation incident on the - diffraction element is generally parallel. As the radiation is parallel, the diffraction pattern caused by the diffraction element (either 304, FIG. 3, or 402, FIG. 4) is generally a Fraunhofer's diffraction pattern, such as that shown in FIG. 5. However, if the radiation falling incident upon the diffraction element (either 304, FIG. 3, or 402, FIG. 4) is not parallel, the diffraction image created would be a Fresnel's diffraction pattern. It is appreciated by those skilled in the art that Fraunhofer and Fresnel diffraction patterns are similar in shape and differ only in the locations of the minimum intensities of the radiation within the diffraction pattern. Thus, this invention will function acceptably regardless of the type of radiation incident upon the diffracting element. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
FIG. 5 illustrates a Frauhofer's diffraction pattern 500 formed by a substantially circular aperture (or lens). The Fraunhofer's diffraction pattern appears as a series of concentric radiation circles 502, 504, 506, and 508 with areas of minimum intensity 510, 512, 514, 516 between each concentric circle, wherein the center circle, referred to in the art as the Airy Spot 512, has the highest radiation intensity'. The radius of the Airy Spot 512 may be calculated by the following formula:
0.611 af where "p" is the radius of the Airy Spot 502, "a" is the diameter of the lens or . aperture within the diffraction element, "f is the distance from the diffraction element to the pixel, and "L" is the wavelength of radiation incident upon the diffraction element (either 302, FIG. 3, or 400, FIG. 4).
For example, a Fraunhoffer's diffraction pattern created by green light (550 nm wavelength) incident upon a diffraction element having a 2 micrometer diameter aperture located at a distance of 8 micrometers between the diffraction element and the pixel would theoretically result in a diffraction pattern with an Airy Spot 502, FIG. 5, having a radius of 0.67. Similarly, a Fraunhofer's diffraction pattern created by red light (650 nm wavelength) incident upon the same diffraction element would result an Airy Spot 510 with a radius of 0.79. A Fraunhofer's diffraction pattern created by blue light (450 nm wavelength) incident upon the same diffraction element (either 302, FIG. 3, or 400, FIG. 4) would result in an Airy Spot 502, FIG. 5, with a radius of 0.55. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
FIG. 6 is a plot 600 of an intensity profile of the Frauhofer's diffraction pattern that may be calculated as
Figure imgf000013_0001
where "Jl" is a Bessel function. The radiation intensity of the Airy Spot 502, FIG. 5, includes about 84% of the total intensity of radiation incident upon the diffraction element. The minimum radiation intensities 602, FIG. 6, 604, and 606 (same as minimum radiation intensities 510, FIG.5, 512, and 514) occur periodically at u = 0.61(PI), 1.22(PI), 1.83(PI), ... 0.61n(PI). The Airy Spot 606, FIG. 6, occurs at the center of the pattern.
The radius of the aperture (or lens) within the diffraction element (either 302, FIG. 3, or 400, FIG. 4) may be determined with reference to the size of the detecting area of the associated pixel and the distance between the pixel and diffraction element. In view of this information, the diffraction element is preferably designed such that the Airy Spot 606, FIG. 6, falls incident within the detecting area. As such, about 84% of the incident radiation intensity falls within the detecting area of an associated pixel. If the pixel requires less than 84% of the incident radiation to generate a charge, the diffraction element may also be designed such that only a portion of the area of the Airy Spot 606 falls within the detecting area. Of course, the diffraction element may also be designed in order to further allow radiation circles 504, FIG. 5, 506, and 508 that are outside the Airy Spot 606, FIG. 6, to also fall PATENT
SNR Matter No. 9785980-0048
00CXT0209I incident within the detecting area, thus further increasing the intensity of radiation incident upon the detecting area.
In the implementation described above, the radius of the aperture (or lens) within the diffraction element is selected in relation to the wavelength of the radiation intended for the pixel associated with the diffraction element. In a typical solid-state image sensor, a plurality of pixels are arranged in an array in order to detect various portions of the radiation spectrum (e.g. blue, green and red for use in the visible spectrum or x-ray, gamma ray, infrared, etc. in the invisible spectrum) over a desirable surface area. In this illustration, a separate diffraction element may be positioned over each pixel. The radius of the lens (or aperture) within each diffraction element is preferably determined in relation to the mean wavelength of red, green, and blue light, such that the radius of the lenses (or apertures) may be uniform throughout each diffraction element associated with the pixel array to simply manufacturing of the diffraction elements, which may be fabricated in a single sheet for placement over the pixel array. Alternatively, the lenses (and apertures) of the diffraction elements may be configured with reference to the average wavelength of red, green, and blue light, the median wavelength, or any other wavelength between the longest (red) and shortest (blue) wavelengths associated with pixels in the pixel array.
In another example implementation shown in FIG. 7, the diffraction element 700 positioned over the first pixel 1 10 may have an aperture (or lens) 702 shaped like a rectangular strip situated within the opaque portion 704 of the diffraction element 700. Similarly, the diffraction element 700 is also positioned over a filter 706, such that radiation is first diffracted by the diffraction element 700 and then filtered by the PATENT
SNR' Matter No. 9785980-0048
00CXT02O91 filter 706. Unlike the prior example having a circular aperture/lens, in this example the diffraction element 700 will create a diffraction pattern having a strip shaped high intensity area, or Airy Strip, at its center.
FIG. 8 illustrates an exemplary diffraction pattern 800 that would be formed by the strip aperture or lens. The size of the Airy Strip 802 created by the rectangular aperture 702 diffraction element 700 can be determined by the following formula:
0.611
P = bf
where "p" is the width of the Airy Strip 802, "b" is the width of the lens or aperture within the diffraction element, "f ' is the distance between the diffraction element 702 and the first pixel 110, and "L" is the wavelength of the radiation. As in the other example implementation, the size of the aperture 702 is determined by the width of the detecting area and the distance of the diffraction element 702 from the first pixel 110. It would be understood by one skilled in the art having this specification before them that this invention may be used in association with various pixel designs in association with various lens (or aperture) shapes as long as a sufficient intensity of radiation created by the diffraction pattern falls incident within the detecting area of the pixels of an array. It would also be understood that the diffraction element may also include multiple apertures or lenses for altering the diffraction pattern.
In another implementation of this invention illustrated in FIG. 9, individual pixels within a pixel array 100, FIG. 1, may be optically separated from neighboring pixels. An opaque wall 900 may be placed between the neighboring pixels 1 10, 120, PATENT
SNR Matter No. 9785980-0048
OOCXT0209I and 130. Preferably, the opaque wall 900 is located along the border of each pixel and is of a sufficient height from the surface of the pixels such that most of the radiation from the diffraction pattern (formed by the diffraction elements 902, 904, and 906 over its associated pixel 1 10, 120 and 130, respectively) is blocked from falling incident upon the surface of a neighboring pixel. The opaque wall 900 may be constructed from silicon or another semiconductor material.
While various implementations of the application have been described, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible that are within the scope of the invention. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents.

Claims

PATENT
SNR Matter No. 9785980-0048
00CXT0209I
What is claimed:
1. A solid-state image sensor having an array of pixels for converting a received radiation spectrum into an electrical signal, the solid state image sensor
5 comprising: a pixel within the array of pixels for detecting a portion of the radiation spectrum and converting the portion of the radiation spectrum into an electrical signal; . and a diffraction element located in physical proximity to the pixel such that some O of the portion of the radiation spectrum incident upon the diffraction element is diffracted onto the pixel.
2. The invention of Claim 1 wherein the portion of the radiation spectrum diffracted by the diffraction element forms a diffraction pattern incident upon the
5 pixel.
3. The invention of Claim 2 wherein the diffraction pattern is Fraunhofer pattern.
:0 4. The invention of Claim 2 wherein the diffraction pattern includes a high intensity area.
The invention of Claim 4 wherein the pixel includes a detecting area. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
6. The invention of Claim 5 wherein a substantial portion of the high intensity area is incident upon the detecting area.
7. The invention of Claim 5 wherein the high intensity area is an Airy Spot.
8. The invention of Claim 5 wherein the high intensity area is an Airy Strip.
9. The invention of Claim 4 wherein the diffraction element includes an opaque area; and a lens situated within the opaque area for diffracting the portion of the radiation spectrum.
10. The invention of Claim 9 wherein a shape of the lens is determined by a shape of a detecting area of the pixel toward optimizing an amount of the high intensity area incident upon the detecting area.
11. The invention of Claim 9 wherein the lens has a radius determined in relation to a detecting area of the pixel.
12. The invention of Claim 11 wherein the lens has a radius further determined in relation to a distance from the pixel to the lens. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
13. The invention of Claim 12 wherein the lens has. a radius further determined in relation to the portion of the radiation spectrum falling incident upon the lens.
14. The invention of Claim 9 wherein the lens has a width determined in relation to a detecting area of the pixel.
15. The invention of Claim 14 wherein the lens has a width further determined in relation to a distance from the pixel to the lens.
16. The invention of Claim 15 wherein the lens has a radius width determined in relation to the portion of the radiation spectrum falling incident upon the lens.
17. The invention of Claim 9 wherein the pixel includes a detecting area that is concentric with the lens.
18. The invention of Claim 4 wherein the diffraction element includes an opaque area having an aperture for diffracting radiation.
19. The invention of Claim 18 wherein the shape of the aperture is determined by the shape of a detecting area of the pixel toward optimizing an amount of the high intensity area incident upon the detecting area. PATENT
SNR Matter No. 9785980-0048
00CXT02091
20. The invention of Claim 18 wherein the pixel includes a detecting area that is concentric with the aperture.
21. The invention of Claim 18 wherein a radius of the aperture is determined in relation to a detecting area of the pixel.
22. The invention of Claim 21 wherein the radius of the aperture is further determined in relation to a distance from the pixel to the lens.
23. The invention of Claim 22 wherein the radius of the aperture is further determined in relation to the portion of the radiation spectrum falling incident upon . the lens.
24. The invention of Claim 18 wherein a width of the aperture is determined in relation to a detecting area of the pixel.
25. The invention of Claim 24 wherein the width of the aperture is further determined in relation to a distance from the pixel to the lens.
26. The invention of Claim 25 wherein the width of the aperture is further determined in relation to the portion of the radiation spectrum falling incident upon the lens.. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
27. The invention of Claim 1 wherein the portion of the radiation spectrum is visible light.
28. The invention of Claim 1 wherein the portion of the radiation spectrum is invisible light selected from the group consisting of: X-ray radiation; Gamma radiation; Ultraviolet light; Microwave radiation; and Infrared Light.
29. A solid-state image sensor having an array of pixels for converting a received radiation spectrum into an electrical signal, the solid state image sensor comprising: a first pixel within the array of pixels for detecting a first portion of the radiation spectrum and converting the first portion of the radiation spectrum into an electrical signal, the first pixel having a detecting area; a second pixel within the array of pixels for detecting a second portion of the radiation spectrum and converting the second portion of the radiation spectrum into an electrical signal; and a first diffraction element located in physical proximity to the first pixel such that a substantial amount of the first portion of the radiation spectrum incident upon the first diffraction element is diffracted onto the first pixel. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
30. The invention of Claim 29 wherein the first diffraction element includes: a first opaque area; and a first lens situated within the first opaque area for diffracting the first portion of the radiation spectrum.
31. The invention of Claim 30 wherein the first lens has a radius that is determined in relation to the mean of the first and second portions of the radiation spectrum.
32. The invention of Claim 31 wherein the radius of the first lens is further determined in relation to the detecting area of the first pixel.
33. The invention of Claim 32 wherein the radius of the first lens is further determined in relation to a distance from the first pixel to the lens.
34. The invention of Claim 30 further including a second diffraction element located in physical proximity to the second pixel such that a substantial amount of the second portion of the radiation spectrum incident upon the second diffraction element is diffracted onto the second pixel. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
35. The invention of Claim 34 wherein the second diffraction element includes: a second opaque area; and a second lens situated within the second opaque area for diffracting the second portion of the radiation spectrum.
36. The invention of Claim 35 wherein the second lens has a radius that is determined in relation to the mean of the first portion of the radiation spectrum and the second portion of the radiation spectrum.
37. The invention of Claim 36 wherein the radius of the second lens is further determined in relation to the detecting area of the second pixel.
38. The invention of Claim 37 wherein the radius of the second lens is further determined in relation to a distance from the second pixel to the lens.
39. The invention of Claim 29 wherein the first diffraction element includes:
. a first opaque area; and a first aperture within the first opaque area for diffracting the first portion of
the radiation spectrum. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
40. The invention of Claim 39 wherein a radius of the first aperture is determined in relation to the mean of the first portion of the radiation spectrum and the second portion of the radiation spectrum.
41. The invention of Claim 39 wherein the radius of the first aperture is further determined in relation to the detecting area of the first pixel.
42. The invention of Claim 41 wherein the radius of the first aperture is further determined in relation to a distance from the first pixel to the diffraction element.
43. The invention of Claim 39 further including a second diffraction element located in physical proximity to the second pixel such that a substantial amount of the second portion of the radiation spectrum incident upon the second diffraction element is diffracted onto the second pixel.
44. The invention of Claim 43 wherein the second diffraction element includes: a second opaque area; and a second aperture within the second opaque. area for diffracting the second portion of the radiation spectrum; wherein a radius of the second aperture is determined in relation to the mean of the first and second portions of the radiation spectrum. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
45. The invention of Claim 44 wherein the radius of the second aperture is further determined in relation to the detecting area of the second pixel.
46. The invention of Claim 45 wherein the radius of the second aperture is further determined in relation to a distance from the second pixel to the aperture.
47. The invention of Claim 29 wherein the first diffraction element includes: a first opaque area; and a first lens situated within the first opaque area for diffracting the first portion of the radiation spectrum; wherein the first lens has a width that is determined in relation to the mean of the first and second portions of the radiation spectrum.
48. The invention of Claim 47 wherein the width of the first lens is further determined in relation to the detecting area of the first pixel.
49. The invention of Claim 48 wherein the width of the first lens is further determined in relation to a distance from the first pixel to the first lens.
50. The invention of Claim 47 further including a second diffraction element located in physical proximity to the second pixel such that a substantial amount of the second portion of the radiation spectrum incident upon the second diffraction element is diffracted onto the first pixel. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
51. The invention of Claim 50 wherein the second diffraction element includes: a second opaque area; and a second lens situated within the second opaque area for diffracting the second portion of the radiation spectrum, wherein the second lens has a width that is determined in relation to the mean of the first and second portions of the radiation spectrum.
52. The invention of Claim 51 wherein the width of the second lens is further determined in relation to the detecting area of the second pixel.
53. The invention of Claim 52 wherein the width of the second lens is further determined in relation to a distance from the second pixel to the second lens.
54. The invention of Claim 29 wherein the first diffraction element includes: a first opaque area; and a first aperture within the first opaque area for diffracting the first portion of the radiation spectrum, wherein a width of the first aperture is determined in relation to the mean of the first and second portions of the radiation spectrum.
55. The invention of Claim 54 wherein the width of the first aperture is further determined in relation to the detecting area of the first pixel. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
56. The invention of Claim 55 wherein the width of the first aperture is further determined in relation to a distance from the first pixel to the first diffraction element.
57. The invention of Claim 55 further including a second diffraction element located in physical proximity to the second pixel such that a substantial amount of the second portion of the radiation spectrum incident upon the second diffraction element is diffracted onto the second pixel.
58. The invention of Claim 57 wherein the second diffraction element includes: a second opaque area; and a second aperture within the second opaque area for diffracting the second portion of the radiation spectrum, wherein a width of the second aperture is determined in relation to the mean of the first and second portions of the radiation spectrum.
59. The invention of Claim 58 wherein the width of the second aperture is further determined in relation to the detecting area of the second pixel.
60. The invention of Claim 59 wherein the width of the second aperture is further determined in relation to a distance from the second pixel to the second aperture. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
61. The invention of Claim 29 wherein the first pixel is adjacent to the second pixel, further including an opaque wall located between the first and second pixels whereby a diffraction pattern formed by the first portion of the radiation spectrum is substantially prevented from falling incident upon the second pixel.
62. The invention of Claim 61 wherein the opaque wall is a silicon wall.
63. The invention of Claim 29 wherein the first pixel is adjacent to the second pixel, further including means for optically separating the first pixel from the second pixel such that a diffraction pattern formed by the first portion of the radiation spectrum is substantially prevented from falling incident upon the second pixel.
64. A solid-state image sensor having an array of pixels for converting a received radiation spectrum into an electrical signal, the solid state image sensor comprising: a pixel within the array of pixels for detecting a portion of the radiation spectrum and converting the portion of the radiation spectrum into an electrical signal; and means for diffracting the portion of the radiation spectrum onto the pixel. PATENT
SNR Matter No. 9785980-0048
00CXT0209I
65. A method for detecting radiation in a solid state image sensor having an array of pixels including a first pixel, comprising: receiving a first portion of the radiation spectrum upon a diffraction element positioned over the first pixel; and diffracting the first portion of the radiation spectrum onto the first pixel such that a diffraction pattern is formed incident upon the first pixel.
66. • The method of Claim 65 further comprising determining a radius of an aperture of the diffraction element in relation to a detecting area of the first pixel.
67. The method of Claim 66 further comprising determining the radius of the aperture in relation to the first portion of the radiation spectrum.
68. The method of Claim 66 further comprising determining the radius of the aperture in relation to a distance from the first pixel to the diffraction element.
69. The method of Claim 65 further comprising determining a radius of a lens of the diffraction element in relation to a detecting area of the first pixel.
70. The method of Claim 69 further comprising determining the radius of the lens in relation to the first portion of the radiation spectrum. PATENT
SNR Matter No. 9785980-0048
00CXTO2O9I
71. The method of Claim 70 further comprising determining the radius of the aperture in relation to a distance from the first pixel to the diffraction element.
72. The method of Claim 71 further comprising separating optically the first pixel from a second pixel adjacent to the first pixel, preventing the diffraction pattern from falling incident upon the second pixel.
PCT/US2002/018586 2001-06-14 2002-06-12 System for diffracting radiation in a solid state image sensor WO2003044831A2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2002364689A AU2002364689A1 (en) 2001-06-14 2002-06-12 System for diffracting radiation in a solid state image sensor

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US88257601A 2001-06-14 2001-06-14
US09/882,576 2001-06-14

Publications (2)

Publication Number Publication Date
WO2003044831A2 true WO2003044831A2 (en) 2003-05-30
WO2003044831A3 WO2003044831A3 (en) 2004-05-21

Family

ID=25380886

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2002/018586 WO2003044831A2 (en) 2001-06-14 2002-06-12 System for diffracting radiation in a solid state image sensor

Country Status (2)

Country Link
AU (1) AU2002364689A1 (en)
WO (1) WO2003044831A2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7808023B2 (en) * 2005-08-24 2010-10-05 Aptina Imaging Corporation Method and apparatus providing integrated color pixel with buried sub-wavelength gratings in solid state imagers

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5438408A (en) * 1991-06-07 1995-08-01 Sympatec Gmbh System-Partikel-Technik Measuring device and method for the determination of particle size distributions by scattered light measurements
US5629802A (en) * 1995-01-05 1997-05-13 The United States Of America As Represented By The Secretary Of The Air Force Spatially multiplexed optical signal processor
US5798864A (en) * 1994-03-24 1998-08-25 Olympus Optical Co., Ltd. Projection type image display apparatus
US5930012A (en) * 1994-09-30 1999-07-27 Cambridge University Technical Services, Ltd. Polarization independent optical switch

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5438408A (en) * 1991-06-07 1995-08-01 Sympatec Gmbh System-Partikel-Technik Measuring device and method for the determination of particle size distributions by scattered light measurements
US5798864A (en) * 1994-03-24 1998-08-25 Olympus Optical Co., Ltd. Projection type image display apparatus
US5930012A (en) * 1994-09-30 1999-07-27 Cambridge University Technical Services, Ltd. Polarization independent optical switch
US5629802A (en) * 1995-01-05 1997-05-13 The United States Of America As Represented By The Secretary Of The Air Force Spatially multiplexed optical signal processor

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7808023B2 (en) * 2005-08-24 2010-10-05 Aptina Imaging Corporation Method and apparatus providing integrated color pixel with buried sub-wavelength gratings in solid state imagers

Also Published As

Publication number Publication date
AU2002364689A1 (en) 2003-06-10
AU2002364689A8 (en) 2003-06-10
WO2003044831A3 (en) 2004-05-21

Similar Documents

Publication Publication Date Title
CN109716176B (en) Light field imaging device and method for depth acquisition and three-dimensional imaging
US8581174B2 (en) Image sensor with prismatic de-multiplexing
TWI458348B (en) Cmos image sensor with improved photodiode area allocation
US7808023B2 (en) Method and apparatus providing integrated color pixel with buried sub-wavelength gratings in solid state imagers
US6958862B1 (en) Use of a lenslet array with a vertically stacked pixel array
US20070298533A1 (en) Method and apparatus providing imager pixel array with grating structure and imager device containing the same
EP2614527B1 (en) Image sensor and image capture apparatus
US8411375B2 (en) Method and apparatus providing gradient index of refraction lens for image sensors
RU2554292C2 (en) Image sensor and imager
JP3170847B2 (en) Solid-state image sensor and optical device using the same
US6753585B1 (en) Vertical color photo-detector with increased sensitivity and compatible video interface
CN102740006B (en) Image sensor and image-capturing apparatus
US20080080028A1 (en) Imaging method, apparatus and system having extended depth of field
KR102372745B1 (en) Image sensor and electronic device having the same
US20060169870A1 (en) Image sensor with embedded optical element
US9921106B1 (en) Integrated imaging spectrometer for hyperspectral imaging systems
JP3571982B2 (en) Solid-state imaging device and solid-state imaging system having the same
KR100572228B1 (en) Solid state imaging device
US6236508B1 (en) Multicolor detector and focal plane array using diffractive lenses
JP5359323B2 (en) Solid-state imaging device and electronic device
US20070210345A1 (en) Solid-state image sensor with micro-lenses for anti-shading
US20020140832A1 (en) Optimization of CCD microlens size for color balancing
US20100309554A1 (en) Color separation microlens and color separation grating
US6744032B1 (en) Arrangement of microlenses in a solid-state image sensor for improving signal to noise ratio
WO2003044831A2 (en) System for diffracting radiation in a solid state image sensor

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A2

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SD SE SG SI SK SL TJ TM TN TR TT TZ UA UG UZ VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A2

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP