Source: http://www.google.com/patents/US20020140990?ie=ISO-8859-1&dq=5,941,947
Timestamp: 2015-01-31 23:51:12
Document Index: 362289663

Matched Legal Cases: ['art 4', 'art 4', 'art 4', 'art 4', 'art 4', 'art 4', 'art 4', 'art 4', 'art 4', 'art 4', 'art 4', 'art 4', 'art 4', 'art 4']

Patent US20020140990 - Focus calibrating method for image scanning device by testing focus chart - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsA focus calibrating method for an image scanning device by testing a focus chart is disclosed. The focus chart has a base sheet and a plurality of black bars with different widths arranged in parallel on the base sheet and spaced from each others. The focus chart is adhered on a bottom surface of a top...http://www.google.com/patents/US20020140990?utm_source=gb-gplus-sharePatent US20020140990 - Focus calibrating method for image scanning device by testing focus chartAdvanced Patent SearchPublication numberUS20020140990 A1Publication typeApplicationApplication numberUS 09/817,284Publication dateOct 3, 2002Filing dateMar 27, 2001Priority dateMar 27, 2001Publication number09817284, 817284, US 2002/0140990 A1, US 2002/140990 A1, US 20020140990 A1, US 20020140990A1, US 2002140990 A1, US 2002140990A1, US-A1-20020140990, US-A1-2002140990, US2002/0140990A1, US2002/140990A1, US20020140990 A1, US20020140990A1, US2002140990 A1, US2002140990A1InventorsRong-Ji LiuOriginal AssigneeRong-Ji LiuExport CitationBiBTeX, EndNote, RefManReferenced by (8), Classifications (24), Legal Events (4) External Links: USPTO, USPTO Assignment, EspacenetFocus calibrating method for image scanning device by testing focus chartUS 20020140990 A1Abstract A focus calibrating method for an image scanning device by testing a focus chart is disclosed. The focus chart has a base sheet and a plurality of black bars with different widths arranged in parallel on the base sheet and spaced from each others. The focus chart is adhered on a bottom surface of a top panel supporting the document positioning plate of the scanner and disposed facing the optical scanning module of the scanner. The focus method includes steps of moving the optical scanning module to read the image data of the focus chart, calculating a focal length value of the image data of the focus chart, judging whether a predetermined optimal focal length is reached or not according to the calculated focal length value, repeatedly moving the optical scanning module with respect to the focus chart to adjust the focal length until the optimal focal length is reached. The focus method further includes a step of setting a preset scanning resolution for selecting a specific black bar during testing the focus chart. Images(7) Claims(6)
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0025] Referring to FIG. 4, it illustrates a pattern of a focus chart in accordance with a preferred embodiment of the present invention. The focus chart 4 comprises a base sheet 41, and a number of black bars 42 arranged in parallel and spaced from each others on the base sheet 41. Each of the black bars 42 further comprises a number of wider black bars 43 a and narrower black bars 43 b of different widths. [0026] With reference to FIG. 5, it is a schematic view showing an optical path of a reflective type image scanning device in accordance with the present invention. The same reference numbers used in the previous drawing will be used to refer to the same or like parts. [0027] A document 2 to be scanned is placed on a document positioning plate 12 of an image scanning device. The document positioning plate 12 is supported by a top panel 11 of the scanner. An optical scanning module 14 is arranged beneath the document positioning plate 12, which is equipped with a light source 16, a plurality of reflective mirrors 171, 172, 173, and 174, a focusing lens 18, and an image sensing module 19. The optical scanning module 14 may be moved by a known driving mechanism (not shown) in a first direction I to scan the document 2 placed on the document positioning plate 12. The first direction I is substantially parallel to the document positioning plate 12 and the movement of the optical scanning module 14. [0028] The focus chart 4 as shown in FIG. 4 is adhered to the bottom surface of the top panel 11 at the initial scanning side 10 of the document positioning plate 12. The extending direction of the black bars 42 is same as the first direction I of the movement of the optical scanning module 14. [0029] A focus adjusting mechanism 5 is capable of moving the optical scanning module 14 in a second direction II substantially perpendicular to the document positioning plate 12 under control of a control unit 6. [0030] With reference to FIGS. 5 and 6, the focusing method of the present invention will be described in more detail below. FIG. 6 shows a control flow chart according to a first embodiment of the present invention. Before scanning the document, the optical scanning module 14 is controlled to scan the focus chart 4 adhered on the bottom surface of the top panel 11. Initially, in step 101, the optical scanning module of the scanner reads the image data of the focus chart 4 by scanning the focus chart 4. Then, the control unit of the scanner calculates the focal length value of the image data of the focus chart 4 in step 102. [0031] In step 103, the control unit judges whether the focusing to the focus chart 4 has been reached by means of the application of, for example, a known approached recognition method. The focus testing procedure will be finished if the focusing has been reached. If the focusing has not been reached yet, the control unit will repeatedly drive the optical scanning module 14 in step 104 to move in the second direction II to adjust the focal length with respect to the focus chart 4, and finally an optimal focal length may be obtained. After the focus testing procedure has been completed, the scanner will perform a formal scanning procedure to scan the document 2 located on the document positioning plate 12. [0032]FIG. 7 is a control flow chart according to a second embodiment of the present invention. This alternative embodiment enables the user to set a desired scanning resolution for the scanner. After the user sets the desired scanning resolution in step 200, the control unit 6 of the scanner automatically selects one specific black bar 42 arranged on the base sheet 41 of the focus chart 4 according to the set scanning resolution for focus testing. [0033] For example, for a low-resolution requirement, the scanner operated in low resolution scanning mode needs only to scan the black bar 42 of relatively broader width. On the contrary, for a high-resolution requirement, the scanner operated in high resolution scanning mode needs only to scan the black bar 42 of relatively narrower width. Normally, the scanner takes a longer time to scan the black bar in high resolution scanning mode than in high resolution scanning mode. [0034] After the setting of the scanning resolution, the optical scanning module of the scanner reads the image data of the specific black bar 42 of the focus chart 4 in step 201 by scanning the focus chart 4. Then, the control unit of the scanner calculates the focal length value of the image data of the specific black bar of the focus chart 4 in step 202. [0035] In step 203, the control unit judges whether the focusing to the specific black bar 42 of the focus chart 4 has been reached. The focus testing procedure will be finished if the focusing has been reached. If the focusing has not been reached yet, the control unit will repeatedly control the optical scanning module 14 in step 204 to move in the second direction II to adjust the focal length with respect to the focus chart 4, and finally an optimal focal length value may be obtained. After the focus testing procedure has been completed, the scanner will perform a formal scanning procedure to scan the document 2 located on the document positioning plate 12. [0036] Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims. Referenced byCiting PatentFiling datePublication dateApplicantTitleUS6813573 *May 3, 2001Nov 2, 2004Hewlett-Packard Development Company, L.P.Apparatus and method for calibration of scan position for a peripheral device with document feederUS6940064 *Feb 24, 2003Sep 6, 2005Laser Sensor Technology, Inc.Method and apparatus for validating the operation of an optical scanning deviceUS7193196 *Oct 29, 2004Mar 20, 2007Lockheed Martin CorporationMethods and systems for evaluating optical systemsUS7522306Feb 11, 2004Apr 21, 2009Hewlett-Packard Development Company, L.P.Method and apparatus for generating a calibration target on a mediumUS7869091Mar 13, 2009Jan 11, 2011Hewlett-Packard Development Company, L.P.Scanner characteristic adjustmentUS8300281 *Sep 17, 2009Oct 30, 2012Microtek International Inc.Calibrating device, mapping method and compensation method using the sameUS20110007367 *Sep 17, 2009Jan 13, 2011Yu Wan-JhangCalibrating device, mapping method and compensation method using the sameWO2012041285A2 *Sep 21, 2011Apr 5, 2012Grenzebach Maschinenbau GmbhDevice and method for detecting flaws in continuously produced float glass* Cited by examinerClassifications U.S. Classification358/406, 358/474, 250/201.2International ClassificationH04N1/00, H04N1/04, G02B7/28Cooperative ClassificationH04N1/00053, H04N1/00045, H04N1/00002, H04N1/00018, G02B7/28, H04N1/00087, H04N1/00063, H04N1/00068, H04N1/00031European ClassificationH04N1/00A3M, H04N1/00A4C5, H04N1/00A3J, H04N1/00A3T, H04N1/00A3W, H04N1/00A2E, H04N1/00A3C, G02B7/28, H04N1/00ALegal EventsDateCodeEventDescriptionAug 14, 2009ASAssignmentOwner name: TRANSPACIFIC SYSTEMS, LLC, DELAWAREFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TRANSPACIFIC IP LTD.;REEL/FRAME:023107/0267Effective date: 20090618Owner name: TRANSPACIFIC SYSTEMS, LLC,DELAWAREFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TRANSPACIFIC IP LTD.;US-ASSIGNMENT DATABASE UPDATED:20100316;REEL/FRAME:23107/267Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TRANSPACIFIC IP LTD.;US-ASSIGNMENT DATABASE UPDATED:20100330;REEL/FRAME:23107/267Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TRANSPACIFIC IP LTD.;US-ASSIGNMENT DATABASE UPDATED:20100413;REEL/FRAME:23107/267Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TRANSPACIFIC IP LTD.;US-ASSIGNMENT DATABASE UPDATED:20100427;REEL/FRAME:23107/267Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TRANSPACIFIC IP LTD.;US-ASSIGNMENT DATABASE UPDATED:20100504;REEL/FRAME:23107/267Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TRANSPACIFIC IP LTD.;US-ASSIGNMENT DATABASE UPDATED:20100511;REEL/FRAME:23107/267Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TRANSPACIFIC IP LTD.;US-ASSIGNMENT DATABASE UPDATED:20100518;REEL/FRAME:23107/267Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TRANSPACIFIC IP LTD.;REEL/FRAME:23107/267Jan 3, 2006ASAssignmentOwner name: TRANSPACIFIC IP, LTD., TAIWANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:VEUTRON CORPORATION;REEL/FRAME:017564/0747Effective date: 20050706Owner name: TRANSPACIFIC IP, LTD.,TAIWANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:VEUTRON CORPORATION;US-ASSIGNMENT DATABASE UPDATED:20100316;REEL/FRAME:17564/747Sep 14, 2005ASAssignmentOwner name: VEUTRON CORPORATION, TAIWANFree format text: CHANGE OF NAME;ASSIGNOR:UMAX DATA SYSTEMS INC.;REEL/FRAME:016800/0203Effective date: 20021029Mar 27, 2001ASAssignmentOwner name: UMAX DATA SYSTEMS, INC., TAIWANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:LIU, RONG-JI;REEL/FRAME:011656/0292Effective date: 20010215RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services