|Publication number||USRE42618 E1|
|Application number||US 11/318,393|
|Publication date||16 Aug 2011|
|Priority date||23 Oct 2000|
|Also published as||US6667818|
|Publication number||11318393, 318393, US RE42618 E1, US RE42618E1, US-E1-RE42618, USRE42618 E1, USRE42618E1|
|Original Assignee||Transpacific Systems, Llc|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (12), Classifications (16), Legal Events (5)|
|External Links: USPTO, USPTO Assignment, Espacenet|
1. Field of Invention
The present invention relates to a scanner and a scanning method. More particularly, the present invention relates to a multiple-field sensor for image scanning.
2. Description of Related Art
Due to the rapid development of multimedia technologies, image processing speed and clarity have become an important consideration in the selection of a scanner by users. However, a scanner operates according to light reflected from a document. Hence, outside light or any irregular dispersion, diffraction may lead to certain degree of distortion for a scanned image. In addition, limitations in the manufacturing of sensors also contribute to the production noise signals that further distort the image.
An attempt to deal with image distortion problem has been proposed in the Taiwan Patent No. 385608. In the invention, a sensor is used to scan a document a multiple of times to obtain a multiple of scanned images. Thereafter, the scanned images are averaged to reduce the amount of distortion to the actual image. However, this and similar type of designs require multiple scanning and the sensor has to shuttle forward and backward many times. Hence, the scanning is time-consuming and highly inefficient.
In brief, common defects of conventional scanning techniques include:
Accordingly, one object of the present invention is to a multiple-field sensor for a scanner suitable for scanning a document. The scanner includes a multiple-field sensor, an average accumulator, and a block of memory. The multiple-field sensor has a plurality of sensing lines for each color channel. Each sensing line picks up a portion of image signal from the document during scanning. The sensing lines scan the same portion of the document to produce corresponding image signals. The average accumulator averages the image signals obtained from the sensing lines of the same color channel to produce an average image signal. The block of memory is used as a storage area for image signals in general and the average image signal in particular. In addition, the scanner further includes a memory read/write address controller. The memory read/write address controller supplies addresses for storing and retrieving the image data and the average image data to and from the memory blocks.
The invention also provides a scanning method that utilizes a multiple-field sensor. The multiple-field sensor has a plurality of sensing lines corresponding to each color channel. Each sensing line can be used for scanning a document to obtain a corresponding portion of the image signal. First, the scanning lines sequentially scan an identical portion of the document to obtain a plurality of image signals. Thereafter, the image signals are averaged to obtain an average image signal. Finally, the average image signal is output. In addition, the step of obtaining an average image signal includes first storing the image signals and then adding up the image signals. Lastly, the sum is averaged to obtain the average image signal. Furthermore, the steps for obtaining an average image signal by the scanning method of this invention are executed in a pipeline mode.
In brief, a multiple-field sensor is used to obtain a multiple of image signals at the same time. The image signals are then accumulated and averaged in a pipeline mode of operation. Hence, image distortion due to noise interference is reduced without increasing scanning time.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,
Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
In this embodiment, light emitted from an identical portion of the scan document 110 will be reflected by the reflecting mirror 120 and transmitted through the lenses 130. Thereafter, according to the sequence arrangement of the sensing elements 142, 144, 146 and the forward-moving direction of the multiple-field sensor 140, the light will shine onto the sensing elements 142, 144 and 146. In other words, the sensing elements 142, 144 and 146 pick up light from the same portion of the scan document 110 and then the scanned image signals are accumulated and averaged. The accumulated average signals thus obtained serves as data for subsequent image processing.
In the second embodiment, the memory read/write address controller 250 mainly serves as a memory administrator. The controller 250 provides the address of stored data to the average accumulator 230 and address for storing the results in the memory 240 after image data is added or averaged by the average accumulator 230.
Obviously, in signal processing,It should be apparent that image signal generated by the sensing line for color channel R can only accumulateis accumulated with image signal generated by other sensing line of the same color channel R to form an average image signal. Image signal of other color channel such as color channel G and color channel B will be unaffected. Similarly, the treatment of other color channels (G and B) will not mixed with the color channel R.
At T=t, image signal obtained by sense element 312 through scanning the portion 310a of the scan document is stored in the memory. At T=2t, the image signal obtained by sense element 312 through scanning the portion 310a of the scan document is added to a previous image signal similarly obtained by the sense element 312 through scanning the identical portion 310a. The result of the addition is stored in the memory. Such accumulation of image signal continues until time T=12t when the image signal obtained by sensing element 334 scanning over the portion 310a of the scan document is also added to the accumulated sum. After the addition of the last image signal, the accumulated sum of the images signals are averaged by the average accumulator 230 shown in
Other portions of the scan document 310 such as 310b and 310c are similarly processed according to the aforementioned method, executing in a pipeline mode. Hence, after obtaining the first average image signal at T=13t, an average image signal is obtained at every interval of t. Although the averaging method can obtain a low noise level scan image, a processing time very close to a conventional scanner is required (the invention requires only an additional 13t to process).
In summary, the scanner in this invention is able to produce low noise level scan images in a very short time.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
|Cited Patent||Filing date||Publication date||Applicant||Title|
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|US4692812 *||10 Mar 1986||8 Sep 1987||Kabushiki Kaisha Toshiba||Picture image reader|
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|US6597401 *||20 Oct 1998||22 Jul 2003||Pentax Corporation||Image reading system with flare compensation|
|TW385608B||Title not available|
|U.S. Classification||358/514, 358/512, 358/517, 250/208.1, 358/408, 348/297|
|International Classification||H04N1/04, H04N1/193, H04N1/48|
|Cooperative Classification||H04N1/1013, H04N1/486, H04N1/193, H04N1/32358|
|European Classification||H04N1/48C, H04N1/193, H04N1/10F|
|14 Aug 2009||AS||Assignment|
Owner name: TRANSPACIFIC SYSTEMS, LLC, DELAWARE
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TRANSPACIFIC IP LTD.;REEL/FRAME:023107/0267
Effective date: 20090618
|14 Feb 2012||CC||Certificate of correction|
|17 Jun 2013||AS||Assignment|
Owner name: TITUSVILLE CANAVERAL LLC, DELAWARE
Free format text: MERGER;ASSIGNOR:TRANSPACIFIC SYSTEMS, LLC;REEL/FRAME:030628/0681
Effective date: 20130213
|18 Jun 2013||AS||Assignment|
Owner name: INTELLECTUAL VENTURES I LLC, DELAWARE
Free format text: MERGER;ASSIGNOR:TITUSVILLE CANAVERAL LLC;REEL/FRAME:030639/0330
Effective date: 20130214
|26 May 2015||FPAY||Fee payment|
Year of fee payment: 12