Title of Invention

A METHOD OF SCANNING A DOCUMENT AND REPRODUCTION OF THE IMAGE

Abstract

ABSTRACT A METHOD OF SCANNING A DOCUMENT AND REPRODUCTION OF THE IMAGE The invention relates to a scanner having two light sources (LightDevI, LightDev2) working in parallel. It describes a method of scanning a document, wherein alternate scan lines are scanned in parallel. The document may also be scanned with the two light sources scanning in parallel from two extreme ends of the scan path. The scanner includes a data-assembling unit, which collects data from the two light sources and combines the chunks of data to create the final image. The data-assembling unit ensures that the data collected from the light sources is assembled and stored appropriately. Figure 3

Full Text

FIELD OF INVENTION The invention in general relates to the field of reproduction of images and in particular to scanning technology. More specifically the invention relates to a method that enables faster scanning in comparison to the traditional method used in scanners and facsimile machines. The invention improves the performance/speed of scanning in a scanner/facsimile machine by introducing parallelism in the scanning mechanism. DESCRIPTION OF RELATED ART The art of scanning is one of the great contributions of digital technology thus helping the conversion of pictures, documents etc. to the digital form. A traditional scanning apparatus is shown in Figure 1 with reference to US Patent: 4,642,679. It comprises of a light source which extends in the longitudinal direction to illuminate the document, one or more mirrors for bending the optical path to make the entire apparatus compact and a line CCD image sensing element (to be referred to as a CCD hereinafter) for converting optical information into an electrical signal. The apparatus also comprises an IC (not shown in the drawing) comprising, e.g., an A/D converter for A/D converting an image signal output from the CCD before the image signal is transferred to an image processing system. The entire scanning process involves the scanning apparatus moving along the longitude of the document and transmitting the bytes of data to an image processing system. The scanning mechanism described above is insufficient when documents need to be scanned at very high resolutions or the document to be scanned is very big. The entire process would require a few seconds to several minutes depending on the scan resolution. It has been observed that incorporation of a certain degree of parallelism could accelerate the existing scanning procedure. This can be achieved if the document is scanned using multiple light sources resulting in the document being scanned in parts in parallel reducing the total scan time considerably. The Japanese patent JP01241518A2 titled "Optical Scanning Device" describes the engagement of multiple laser/light sources to scan a document with plural light beams running fast in parallel in which the shaping light emitted by each light source is such that the light projected by the (i)th light source among plural light sources illuminates an (i)th area. According to the above patent three hologram lenses are arranged one over another in a radial direction and light beams emitted by the three lasers illuminate individual hologram lenses. The three holograms differ greatly in spatial frequency and are scanned on a scanning surface at distant positions simultaneously. It illustrates that when (n) lasers are used, (n) scanning lines are generated at the same time and hence achieving a scanning speed that is (n) times as fast as the speed of scanning one line. Another example of scanning using multiple light sources is known from US6433907. The scanner, as described in this patent includes a plurality of mirrors, which sweep their beams through respective regions of image field. These regions of image field are immediately adjacent so that an overall image can be produced by tiling of the regions. The scanning assembly scans a plurality of tiles simultaneously, thereby increasing the resolution for a given scan angle relative to a single mirror. The patent publication also describes a scanning mechanism that scans both horizontally and vertically along continuous scan paths. The each beam in this mechanism defines a discrete tile of an image. It is understood from the prior description that the existing art deals with scanning the document with multiple lasers from one end of the document only. In the light of the foregoing the present invention confers a mechanism for scanning of the document from either ends of the document thereby achieving faster scanning and better resolution. The invention also provides a method for scanning alternate lines of the document. In the first case the scanner beam/light sources are at either ends of the flat bed and in the second case the light sources are on the same end of the flat bed. SUMMARY OF THE INVENTION The primary object of the invention is therefore to provide a method for improving the performance/speed of scanning in a scanner/facsimile machine by introducing parallelism in the scanning mechanism so that scanning of the document is performed from either ends of the document. It is another object of the invention to provide a method of scanning the alternate lines of the document and thereby boosting the performance/speed of scanner/facsimile machines. It is yet another object of the invention to improve the pace and resolution of scanning by introducing a better degree of parallelism. It is also an object of the invention to provide a scanning method that scans the documents using multiple light sources in parallel reducing the scanning time significantly. Parallelism could be achieved by using multiple set of image acquisition apparatus comprising of a light source, mirrors, lens and sensors. Now when the scan is initiated, the light sources will move in parallel, scanning different portions of the document in parallel. This results in a significant gain in performance/speed. Accordingly, the invention provides a method of scanning a document and reproduction of the image by means of parallel processing using multiple image acquisition apparatuses, the method comprising the steps of: a) scanning the lines from the left/top extreme using a first image acquisition apparatus (LightDevI); b) scanning the lines from the right/bottom extreme using a second image acquisition apparatus (LightDev2); c) collecting the scanned data in a data buffer and transferring to a transmission buffer for transmitting to the assembling unit; and d) assembling the chunks of data and creating the final image. Accordingly, the invention further provides a method of scanning a document and reproduction of the image by means of parallel processing using multiple image acquisition apparatuses, the method comprising the steps of: a) scanning the odd lines from the left extreme using a first image acquisition apparatus (LightDevI); b) scanning the even lines from the right extreme using a second image acquisition apparatus (LightDev2); c) collecting the scanned data in a data buffer and transferring to a transmission buffer for transmitting to the assembling unit; and d) assembling the chunks of data and creating the final image. These and other objects, features and advantages of the present invention will become more readily apparent from the detailed description taken in conjunction with the accompanying drawings. BREIF DESCRIPTION OF THE ACCOMPANYING DRAWINGS Figure 1 depicts a scanning apparatus for carrying out the method as per prior art. Figure 2 describes the scanning method 1 according to the present invention where scanning is performed from either ends. Figure 3 illustrates the scanning method 2 according to the invention where parallelism is employed to scan alternate lines. DETAILED DESCRIPTION OF THE INVENTION The preferred embodiments of the present invention will now be explained with reference to the accompanying drawings. It should be understood however that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. The following description and drawings are not to be construed as limiting the invention and numerous specific details are described to provide a thorough understanding of the present invention, as the basis for the claims and as a basis for teaching one skilled in the art how to make and/or use the invention. However in certain instances, well-known or conventional details are not described in order not to unnecessarily obscure the present invention in detail. The present invention intend to provide a sophisticated method for scanning strategy that scans the document using multiple light sources in parallel thus reducing the scanning time significantly. High-resolution scan could require several minutes before completing the scan process. This is partly because high resolution scans demands scanning more pixels of the document, the result of which is more bytes of data that requires more time to scan-store-transmit. Parallelism could be achieved by using multiple set of image acquisition apparatus comprising of a light source, mirrors, lens and sensors. Therefore the following should essentially form part of the scanning mechanism: 1. Multiple light sources and associated apparatus. 2. A means to transmit bulk of data (scanning proceeds with a certain amount of parallelism). 3. Multiple processors to process the data from the two light sources in parallel in order to achieve true parallelism and associated boost in performance. The method applies two sets of image acquisition apparatus in the scanner device (instead of one). So there will be two sets of light sources, mirrors and sensor components. This will be referred as LightDevI and LightDev2. With this parallelism in place at any given instant 2n scan lines will have been scanned when compared to n scan lines if only 1 light source, LightDevI was used. This can reduce scan time significantly if n is very large (for scanning large documents) or for high resolution scan. The invention adopts any of the following strategies for achieving parallelism. The scanning is performed with two image acquisition apparatuses LightDevI and LightDev2 comprising of light source, mirrors, lens and sensor 1) Scanning in parallel from the two extreme ends of the scan path. Here the two light sources LightDevI and LightDev2 start reading the scan Lines from the two extreme ends of the scan path. It is diagrammatically represented in Fig 2. LightDevI reads the scan lines from the left/top extreme whereas LightDev2 reads the scan lines from the right/bottom extreme of the document. The position of the scan heads will be at the either extremes initially. During scanning the scan heads move from either heads to the center of the flat bed. So when LightDevI reads scan line 1, LightDev2 reads the MAX scan line in parallel where MAX represents the last scan line. LightDevI reads from scan line 1 to MAX/2 -1. The LightDev2 reads scan lines from MAX to MAX/2. Hence there is a two-fold increase in scan speed. 2) Scanning alternate scan lines in parallel: In this method LightDevI reads the odd scan lines and LightDev2 reads the even scan lines of the document scanned as represented in Fig 3. The scan heads will be at the left extreme of the scanner bed. So when LightDevI is reading the nth scan line, LightDev2 is in parallel scanning the n+1th scan line. Thus the scan duration is typically halved compared to the traditional scanning systems. In both the above cases the scan head is moved slowly across the document by a belt that is attached to a stepper motor. Since we have two scan heads we would need a pair of stepper motors with belts to move the individual scan heads. The scan heads are attached to a stabilizer bar to ensure that there is no wobble or deviation in the pass. Note that the physical parts used are the same as in a conventional facsimile machine. The only difference is that a pair of such setup A/ill be needed for the scan heads. The scanner uses a memory unit (data buffer) for collection of scanned data and another memory unit (transmission buffer) to transmit the data to the PC through USB/Parallel Port/SCSI ports. As the scanner head moves and scans the document, the scan data is stored in the data buffer and periodically transferred to the transmission buffer for transmission to the PC. In the new strategies presented above the only change is in the use of two data buffers for each of the scanner heads and 1 transmission buffer for transmission of the data to the PC. The data transmitted to the host PC would be in chunks of data (as in a normal traditional scan approach). The software that runs on the PC side, collects the data, assembles the data and creates the final scan image. The chunks of data received from either of the scan needs to be stored separately and then assembled later. The following are the advantages of this method over the traditional method: • This method ensures faster scans. • The speed difference is significant if the document scanned is very long or if it is a high resolution scan. • This approach provides a two-fold improvement in scan speed over the current method. • The strategy depicted in the invention could be used across all high-end scanners and facsimile machines to improve performance and speed. It will also be obvious to those skilled in the art that other control methods and apparatuses can be derived from the combinations of the various methods and apparatuses of the present invention as taught by the description and the I ' accompanying drawings and these shall also be considered within the scope of the present invention. Further, description of such combinations and variations is therefore omitted above. It should also be noted that the host for storing the applications include but not limited to a computer, mobile communication device, mobile server or a multi function device. Although the present invention has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that vanous changes and modifications are possible and are apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims unless they depart there from. WE CLAIM 1. A method of scanning a document and reproduction of the image by means of parallel processing using multiple image acquisition apparatuses, the method comprising the steps of: a) scanning the lines from the left/top extreme using a first image acquisition apparatus (LightDevI); b) scanning the lines from the right/bottom extreme using a second image acquisition apparatus (LightDev2); c) collecting the scanned data in a data buffer and transferring to a transmission buffer for transmitting to the assembling unit; and d) assembling the chunks of data and creating the final image. 2. A method of scanning a document and reproduction of the image by means of parallel processing using multiple image acquisition apparatuses, the method comprising the steps of: a) scanning the odd lines from the left extreme using a first image acquisition apparatus (LightDevI); b) scanning the even lines from the left extreme using a second image acquisition apparatus (LightDev2); c) collecting the scanned data in a data buffer and transferring to a transmission buffer for transmitting to the assembling unit; and d) assembling the chunks of data and creating the final image. 3. The method as claimed in claims 1 or 2 wherein the image acquisition apparatus comprises of a light source, mirrors, lens and sensors. 4. The method according to claim 1 wherein the image acquisition apparatuses are on either ends of the flat bed initially and move from either heads to the center of the flat bed during scanning. 5. The method as claimed in claims 1 or 2 wherein the scan heads are moved slowly across the document by a belt that is attached to a stepper motor. 6. The method as claimed in claims 1 or 2 wherein the assembling of chunks of data to create the final image is performed by software running in PC. 7. The method according to claim 7 wherein the data to the PC is transmitted through USB/Parallel Port/SCSI ports. 8. A method of scanning of a document and reproduction of the image by means of parallel processing using multiple image acquisition apparatuses, substantially as herein above described and illustrated with reference to the accompanying drawings.

Documents:

320-che-2005 abstract duplicate.pdf

320-che-2005 abstract.pdf

320-che-2005 claims duplicate.pdf

320-che-2005 claims.pdf

320-che-2005 correspondence others.pdf

320-che-2005 correspondence po.pdf

320-che-2005 description (complete) duplicate.pdf

320-che-2005 description (complete).pdf

320-che-2005 drawings duplicate.pdf

320-che-2005 drawings.pdf

320-che-2005 form-1.pdf

320-che-2005 form-13.pdf

320-che-2005 form-18.pdf

320-che-2005 form-26.pdf

320-che-2005 form-9.pdf