US6069377A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image sensor incorporating saturation time measurement to increase dynamic range
Assignee: Omnivision Technologies Inc
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Filing: 1999-05-13
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Granted: 2000-05-30
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Expires: 2019-05-13
Abstract
Abstract A semiconductor based image sensor having a timer that is associated with each photosite in the image sensor; and measuring the integration period of that photosite using the timer. Additionally, an imager sensor that does not require an A/D converter but instead uses a comparator circuit to determine when a predetermined threshold has been reached, thus reading as discrete amounts of stored charge which converts directly into a digital representation.
Inventors
- 👤 Wayne E. Prentice
- 👤 Robert M. Guidash
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:48
CPC Classifications
H; H10; H10F; H10F39/00; H10F39/10; H10F39/12; H10F39/80; H10F39/803; H04; H04N; H04N25/00; H04N25/50; H04N25/57; H04N25/70; H04N25/76; H04N25/77; H04N25/772; H04N25/78
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
55 words
An active pixel sensor having a plurality of pixels with at least one pixel comprising: a photodetector operatively coupled to a reset device; a threshold level coupled to the photodetector and a device that indicates when the photodetector has reached the threshold level; and an analog detector interfacing the photodetector signal to a signal buss.
Claim 2
Dependent Claim
55 words
An active pixel sensor having a plurality of pixels with at least one pixel comprising: a photodetector operatively coupled to a reset device; a threshold level coupled to the photodetector and a device that indicates when the photodetector has reached the threshold level; and an analog detector interfacing the photodetector signal to a signal buss.
Claim 3
Dependent Claim
17 words
The invention of claim 1 wherein the device further comprises a comparator connected to the threshold level.
Claim 4
Dependent Claim
59 words
The invention of claim 2 wherein the device further comprises: the comparator being connected to the threshold level such that the comparator will trigger when the photodetector potential reaches the level of the threshold buss; and an interface between the comparator output of the pixel and the active pixel sensor identifying when the photodetector reaches the threshold buss potential.
Claim 5
Dependent Claim
39 words
The invention of claim 1 wherein the active pixel sensor further comprises means for combining the signals from the device and the signal buss to arrive at a combined signal level representing an extended dynamic range of the photodetector.
Claim 6
Dependent Claim
40 words
The invention of claim 2 wherein the photodetector is reset upon the comparator firing and the interface is connected to means for cumulatively combining repetitive firings of the comparator yielding a further increase in the dynamic range of the photodetector.
Claim 7
Dependent Claim
16 words
The invention of claim 5 wherein the photodetector is not reset upon firing of the comparator.
Claim 8
Dependent Claim
42 words
The invention of claim 3 wherein the interface further comprises a capacitive element electrically connected to a time dependent signal, the capacitive element operative to store a voltage that is indicative of time required for the photodetector to reach the threshold level.
Claim 9
Dependent Claim
21 words
The invention of claim 7 wherein the interface further comprises a bus supplying a varying analog voltage to the capacitive element.
Claim 10
Dependent Claim
37 words
The invention of claim 8 wherein the interface further comprising a transistor the selectively connects and disconnects the capacitive element from the varying analog voltage bus upon respective reset and achievement of threshold levels of the photodetector.
Claim 11
Dependent Claim
28 words
The invention of claim 9 wherein the capacitive elements retains a voltage of the varying analog voltage bus at the time when the photodetector reached the threshold level.
Claim 12
Dependent Claim
87 words
An active pixel sensor having a plurality of pixels with at least one pixel comprising: a photodetector operatively coupled to a reset device; a threshold level coupled to the photodetector and a device that indicates when the photodetector has reached the threshold level and the photodetector is reset each time the device indicates that the photodetector has reached the threshold level; an analog detector interfacing the photodetector signal to a signal buss; and means for determining the number of times the photodetector has reached the threshold level.
Claim 13
Dependent Claim
87 words
An active pixel sensor having a plurality of pixels with at least one pixel comprising: a photodetector operatively coupled to a reset device; a threshold level coupled to the photodetector and a device that indicates when the photodetector has reached the threshold level and the photodetector is reset each time the device indicates that the photodetector has reached the threshold level; an analog detector interfacing the photodetector signal to a signal buss; and means for determining the number of times the photodetector has reached the threshold level.
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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) | 2003-05-30 | 2003-11-29 | 2004-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-05-30 | 2007-11-29 | 2008-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-05-30 | 2011-11-29 | 2012-05-30 | $7700.00 | Window Closed / Lapsed |