US4698685A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method for correcting CCD pixel nonuniformities
Assignee: RCA Licensing Corp
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Filing: 1986-05-28
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Granted: 1987-10-06
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Expires: 2006-05-28
Abstract
Abstract Nonuniformities in the pixel of a CCD are corrected by storing a correction value for every pixel of the CCD. The pixel values from the CCD are transferred to a multiplier. The correction values are also transferred to the multiplier in synchronization with the transfer of the pixel values. The correction values and the pixel values are multiplied to produce a corrected pixel value for every pixel of the CCD. The corrected pixel values are transferred to an image processor for appropriate data processing.
Inventors
- 👤 Gregory K. Beaverson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:17
CPC Classifications
H; H04; H04N; H04N25/00; H04N25/60; H04N25/67; H04N25/671; H04N25/672
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
136 words
A method of correcting for nonuniformities of the pixels of a charge coupled device (CCD) utilized in a system having a camera for imaging objects onto said CCD whereby the pixels of said CCD are charged to various pixel levels, comprising the steps of: storing an individual correction value for every pixel of said CCD in a central processing unit (CPU); transferring said pixel levels from said CCD to a multiplier; temporarily storing said correction values in a temporary storage unit; transferring said correction values from said temporary storage unit to said multiplier in synchronization with the transfer of said pixel levels whereby every pixel level is multiplied by an individual correction value to produce a corrected pixel value for every pixel of said CCD; and transferring said corrected pixel values to an image processing unit.
Claim 2
Independent Claim
136 words
A method of correcting for nonuniformities of the pixels of a charge coupled device (CCD) utilized in a system having a camera for imaging objects onto said CCD whereby the pixels of said CCD are charged to various pixel levels, comprising the steps of: storing an individual correction value for every pixel of said CCD in a central processing unit (CPU); transferring said pixel levels from said CCD to a multiplier; temporarily storing said correction values in a temporary storage unit; transferring said correction values from said temporary storage unit to said multiplier in synchronization with the transfer of said pixel levels whereby every pixel level is multiplied by an individual correction value to produce a corrected pixel value for every pixel of said CCD; and transferring said corrected pixel values to an image processing unit.
Claim 3
Dependent Claim
28 words
The method of claim 1 further including the step of transferring said pixel levels directly to said image processing unit when said correction values are to be generated.
Claim 4
Dependent Claim
23 words
The method of claim 2 wherein said correction values are transferred to said temporary storage unit in a plurality of separate data blocks.
Claim 5
Dependent Claim
61 words
The method of claim 3 wherein said correction values are calculated in accordance with: CV.sub.N =MEAN A/MEAN N where: CV N =correction value for a particular pixel MEAN A=a mean pixel value obtained from all CCD pixels for a plurality of exposures MEAN N=the mean pixel value for each particular pixel for a plurality of exposures. N=pixel 1, pixel 2, etc.
Claim 6
Dependent Claim
22 words
The method of claim 1 wherein said correction values are transferred to said temporary unit in a plurality of separate data blocks.
Claim 7
Dependent Claim
61 words
The method of claim 5 wherein said correction values are calculated in accordance with: CV.sub.N =MEAN A/MEAN N where: CV N =correction value for a particular pixel MEAN A=a mean pixel value obtained from all CCD pixels for a plurality of exposures MEAN N=the mean pixel value for each particular pixel for a plurality of exposures. N=pixel 1, pixel 2, etc.
Claim 8
Independent Claim
121 words
An apparatus for correcting for nonuniformities of the pixels of a charge coupled device (CCD) within an imaging camera whereby each pixel of said CCD is charged to a pixel level comprising: multiplier means for receiving said pixel values from said CCD; temporary storage means for receiving pixel correction values from a control processing unit and for transferring said correction values to said multiplier in synchronization with the transfer of said pixel values to said multiplier whereby every pixel value is multiplied by an individual correction value to provide a corrected pixel value for every pixel of said CCD; multiplexer means for receiving said corrected pixel values from said multiplier and for providing said corrected pixel values to a processing unit.
Claim 9
Independent Claim
121 words
An apparatus for correcting for nonuniformities of the pixels of a charge coupled device (CCD) within an imaging camera whereby each pixel of said CCD is charged to a pixel level comprising: multiplier means for receiving said pixel values from said CCD; temporary storage means for receiving pixel correction values from a control processing unit and for transferring said correction values to said multiplier in synchronization with the transfer of said pixel values to said multiplier whereby every pixel value is multiplied by an individual correction value to provide a corrected pixel value for every pixel of said CCD; multiplexer means for receiving said corrected pixel values from said multiplier and for providing said corrected pixel values to a processing unit.
Claim 10
Dependent Claim
20 words
The apparatus of claim 7 further including correction control means for controlling said multiplier means and said temporary storage means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-10-05 | 1991-04-06 | 1991-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-05 | 1995-04-06 | 1995-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-05 | 1999-04-06 | 1999-10-06 | $7700.00 | Window Closed / Lapsed |