Patent US5652641A successfully refreshed from Google Patents.
US5652641A
Expired / Lapsed
US
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Method of detecting eye component information for determining sight axis direction, and sight axis direction detection apparatus
Assignee: Canon Inc
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Filing: 1995-04-28
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Granted: 1997-07-29
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Expires: 2015-04-28
Abstract
Abstract In a pupil center detection method and a pupil ring portion detection method, which can obtain a pupil center and a pupil ring portion necessary for calculating a sight axis of an eyeball from specific points on the basis of a light beam reflected by the eyeball, when the position of the pupil center of the eyeball is detected by utilizing an image based on a light beam radiated from a projection device onto the eyeball and reflected by the eyeball, a large number of pupil ring portion positions are obtained, an average value and a standard deviation of the large number of pupil ring portion positions are obtained, and the pupil center is detected using values within a range defined by the average value and the standard deviation.
Inventors
- 👤 Kazuki Konishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:13
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/11; A61P; A61P3/00; G; G03; G03B; G03B13/00; G03B13/02; G03B2213/00; G03B2213/02; G03B2213/025
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
102 words
A method for detecting an edge of an image formed on a pixel array provided with a plurality of pixels, said method comprising: a first step of detecting monotonically increasing or decreasing portions of a signal of the pixel array; a second step of selecting any of said monotonically increasing or decreasing portions detected by said first step whose number of pixels is equal to or more than a predetermined number of pixels; and a third step of determining a position of the edge of the image based on the position of monotonically increasing or decreasing portions selected by said second step.
Claim 2
Independent Claim
102 words
A method for detecting an edge of an image formed on a pixel array provided with a plurality of pixels, said method comprising: a first step of detecting monotonically increasing or decreasing portions of a signal of the pixel array; a second step of selecting any of said monotonically increasing or decreasing portions detected by said first step whose number of pixels is equal to or more than a predetermined number of pixels; and a third step of determining a position of the edge of the image based on the position of monotonically increasing or decreasing portions selected by said second step.
Claim 3
Dependent Claim
48 words
A method according to claim 1, wherein said third step determines a position of a pixel, where the signal starts monotonically increasing or decreasing, of pixels included in said any of said monotonically increasing or decreasing portions selected by said second step as the position of the edge.
Claim 4
Independent Claim
157 words
A method for detecting an edge of an image formed on a pixel array provided with a plurality of pixels, said method comprising: a first step of setting a reference level based on at least one signal level of a plurality of signal levels detected by said plurality of pixels; a second step of selecting a reference pixel having a signal level near the reference level set in said first step; a third step of detecting monotonically increasing or decreasing portions of a signal from the reference pixel and pixels neighboring the reference pixel; a fourth step of selecting any of said monotonically increasing or decreasing portions detected by said third step whose number of pixels is equal to or more than a predetermined number of pixels; and a fifth step of determining a position of the edge of the image based on a position of the monotonically increasing or decreasing portions selected by said fourth step.
Claim 5
Independent Claim
157 words
A method for detecting an edge of an image formed on a pixel array provided with a plurality of pixels, said method comprising: a first step of setting a reference level based on at least one signal level of a plurality of signal levels detected by said plurality of pixels; a second step of selecting a reference pixel having a signal level near the reference level set in said first step; a third step of detecting monotonically increasing or decreasing portions of a signal from the reference pixel and pixels neighboring the reference pixel; a fourth step of selecting any of said monotonically increasing or decreasing portions detected by said third step whose number of pixels is equal to or more than a predetermined number of pixels; and a fifth step of determining a position of the edge of the image based on a position of the monotonically increasing or decreasing portions selected by said fourth step.
Claim 6
Dependent Claim
26 words
A method according to claim 3, wherein said fifth step determines a position of the reference pixel as the position of the edge of the image.
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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) | 2000-07-28 | 2001-01-27 | 2001-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-07-28 | 2005-01-27 | 2005-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-07-28 | 2009-01-27 | 2009-07-29 | $7700.00 | Window Closed / Lapsed |