US6201619B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Autofocus process and system with fast multi-region sampling
Assignee: Agfa Corp
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Filing: 1998-06-18
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Granted: 2001-03-13
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Expires: 2018-06-18
Abstract
Abstract An autofocus process for imaging optics of a scanner comprises performing multiple scan-line image captures of the document to be scanned. In the preferred embodiment, these captures are of essentially the same scan-line. A focal position of imaging optics, which forms a scan-line image, is adjusted relative to an image detector in between the multiple scan-line captures of image data. In the preferred embodiment, the imaging optics is adjusted. Relay optics or a position of the image detector could alternatively be adjusted. In any case, a focus setting for a subsequent scanning operation is then calculated based on the image data from the multiple scan-line captures. In the preferred embodiment, this calculation yields a lens position for the imaging optics. The invention thus allows autofocussing to the document to be scanned. Problems associated with loss of calibration are avoided. Moreover, the system is able to adapt to documents where the image is not at the scanner's nominal focal plane.
Inventors
- 👤 Timothy E. Neale
- 👤 Richard J. Strazdas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:54
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/024; H04N1/02409; G; G02; G02B; G02B7/00; G02B7/02; G02B7/04; G02B7/08; G02B7/28; G02B7/36; H04N1/04; H04N1/0464; H04N1/0467; H04N1/10; H04N1/1013; H04N1/1017; H04N1/1026; H04N1/1039; H04N1/1043; H04N1/1048; H04N1/1052; H04N1/19; H04N1/191; H04N1/192; H04N1/193
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
80 words
An image-scanning device having an autofocus capability, the device comprising: an image detector that generates image data; imaging optics that forms an image on the image detector; relay optics that picks-off an image of a region from media being scanned; focus actuator that adjusts a focal position of the imaging optics relative to the image detector; and a control system that modulates the focus actuator based on the image data from multiple region image captures and for each primary color.
Claim 2
Dependent Claim
80 words
An image-scanning device having an autofocus capability, the device comprising: an image detector that generates image data; imaging optics that forms an image on the image detector; relay optics that picks-off an image of a region from media being scanned; focus actuator that adjusts a focal position of the imaging optics relative to the image detector; and a control system that modulates the focus actuator based on the image data from multiple region image captures and for each primary color.
Claim 3
Dependent Claim
28 words
An image-scanning device as described in claim 1 , wherein the control system prepares image detector electronics for a scan and then performs the multiple region image captures.
Claim 4
Dependent Claim
42 words
An image-scanning device as described in claim 1 , further comprising a carriage, which carries the image detector and imaging optics, and which the control system moves to a predetermined position prior to performing the multiple image captures of the same region.
Claim 5
Dependent Claim
36 words
An image-scanning device as described in claim 1 , wherein the control system analyzes the image data to determine whether it is indicative of a focus position prior to the calculation of a focus position location.
Claim 6
Dependent Claim
110 words
An image-scanning device having an autofocus capability, the device comprising: an image detector that generates image data; imaging optics that forms an image on the image detector; relay optics that picks-off an image of a region from media being scanned; focus actuator that adjusts a focal position of the imaging optics relative to the image detector; and a control system that modulates the focus actuator based on the image data from multiple region image captures and retrieves a stored best focus position and adjusts the focus actuator to move the imaging optics to the stored best focus position when the image data is not indicative of a best focus position.
Claim 7
Dependent Claim
110 words
An image-scanning device having an autofocus capability, the device comprising: an image detector that generates image data; imaging optics that forms an image on the image detector; relay optics that picks-off an image of a region from media being scanned; focus actuator that adjusts a focal position of the imaging optics relative to the image detector; and a control system that modulates the focus actuator based on the image data from multiple region image captures and retrieves a stored best focus position and adjusts the focus actuator to move the imaging optics to the stored best focus position when the image data is not indicative of a best focus position.
Claim 8
Dependent Claim
26 words
An imaging-scanning device as described in claim 5 , wherein the control system controls the focus actuator in response to image data for three separate colors.
Claim 9
Dependent Claim
37 words
An imaging-scanning device as described in claim 5 , wherein the control system controls the focus actuator in response to image data for a color giving rise to image data that is most descriptive of focus position.
Claim 10
Dependent Claim
96 words
An image-scanning device having an autofocus capability, the device comprising: an image detector that generates image data; imaging optics that forms an image on the image detector; relay optics that picks-off an image of a region from media being scanned; focus actuator that adjusts a focal position of the imaging optics relative to the image detector; and a control system that modulates the focus actuator based on the image data from multiple region image captures and corrects for magnification changes caused by adjustment in the focal position of the imaging optics between separate scan-line image captures.
Claim 11
Dependent Claim
96 words
An image-scanning device having an autofocus capability, the device comprising: an image detector that generates image data; imaging optics that forms an image on the image detector; relay optics that picks-off an image of a region from media being scanned; focus actuator that adjusts a focal position of the imaging optics relative to the image detector; and a control system that modulates the focus actuator based on the image data from multiple region image captures and corrects for magnification changes caused by adjustment in the focal position of the imaging optics between separate scan-line image captures.
Claim 12
Dependent Claim
120 words
An image-scanning device having an autofocus capability, the device comprising: an image detector that generates image data; imaging optics that forms an image on the image detector; relay optics that picks-off an image of a region from media being scanned; focus actuator that adjusts a focal position of the imaging optics relative to the image detector; and a control system that modulates the focus actuator based on the image data from multiple region image captures and identifies image data groups from multiple analysis regions of the scanned images to correct for magnification changes caused by adjustment in the focal position of the imaging optics between separate scan-line image captures and calculates a best focus based on the image data groups.
Claim 13
Dependent Claim
120 words
An image-scanning device having an autofocus capability, the device comprising: an image detector that generates image data; imaging optics that forms an image on the image detector; relay optics that picks-off an image of a region from media being scanned; focus actuator that adjusts a focal position of the imaging optics relative to the image detector; and a control system that modulates the focus actuator based on the image data from multiple region image captures and identifies image data groups from multiple analysis regions of the scanned images to correct for magnification changes caused by adjustment in the focal position of the imaging optics between separate scan-line image captures and calculates a best focus based on the image data groups.
Claim 14
Dependent Claim
99 words
An image-scanning device having an autofocus capability, the device comprising: an image detector that generates image data; imaging optics that forms an image on the image detector; relay optics that picks-off an image of a region from media being scanned; focus actuator that adjusts a focal position of the imaging optics relative to the image detector; and a control system that modulates the focus actuator based on the image data from multiple region image captures and controls the focus actuator in response to all colors for a subsequent scanning operation based on image data from less than all colors.
Claim 15
Dependent Claim
99 words
An image-scanning device having an autofocus capability, the device comprising: an image detector that generates image data; imaging optics that forms an image on the image detector; relay optics that picks-off an image of a region from media being scanned; focus actuator that adjusts a focal position of the imaging optics relative to the image detector; and a control system that modulates the focus actuator based on the image data from multiple region image captures and controls the focus actuator in response to all colors for a subsequent scanning operation based on image data from less than all colors.
Claim 16
Dependent Claim
93 words
An autofocus process for imaging optics of an image acquisition device, the process comprising: performing multiple image captures of sections of a document to be imaged; adjusting a focal position of imaging optics, which forms an image, relative to an image detector in between the multiple image captures of image data from the image detector; and calculating a focus setting for a subsequent imaging operation based on the image data from the multiple image captures by calculating a best combined focus for all colors based on image data from less than all colors.
Claim 17
Dependent Claim
93 words
An autofocus process for imaging optics of an image acquisition device, the process comprising: performing multiple image captures of sections of a document to be imaged; adjusting a focal position of imaging optics, which forms an image, relative to an image detector in between the multiple image captures of image data from the image detector; and calculating a focus setting for a subsequent imaging operation based on the image data from the multiple image captures by calculating a best combined focus for all colors based on image data from less than all colors.
Claim 18
Dependent Claim
107 words
An autofocus process for imaging optics of an image acquisition device, the process comprising: performing multiple image captures of sections of a document to be imaged; adjusting a focal position of imaging optics, which forms an image, relative to an image detector in between the multiple image captures of image data from the image detector; and calculating a focus setting for a subsequent imaging operation based on the image data from different image data groups corresponding to a common analysis region of an image section to correct for magnification changes caused by adjustment in the focal position of the imaging optics between separate captures of image sections.
Claim 19
Dependent Claim
107 words
An autofocus process for imaging optics of an image acquisition device, the process comprising: performing multiple image captures of sections of a document to be imaged; adjusting a focal position of imaging optics, which forms an image, relative to an image detector in between the multiple image captures of image data from the image detector; and calculating a focus setting for a subsequent imaging operation based on the image data from different image data groups corresponding to a common analysis region of an image section to correct for magnification changes caused by adjustment in the focal position of the imaging optics between separate captures of image sections.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-03-12 | 2004-09-11 | 2005-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-03-12 | 2008-09-11 | 2009-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-03-12 | 2012-09-11 | 2013-03-13 | $7700.00 | Window Closed / Lapsed |