Abstract:
An image reading apparatus which reads out a document, such as as a book, placed face-up and opened on a document table. The apparatus includes an image reading device for reading out the document image placed on the document table, a mirror for imaging the document upper side plane, a projecting device which projects marks onto the document and mirror, and an image processing unit. A document characterized portion imaged on the mirror is read out by the image reading device and the image processing unit rectifies image distortion of the read out document image based on the characterized portion.
Abstract:
An apparatus for reading an image of the obverse side of a thin sheet includes a light source for emitting a light for illuminating the obverse side of the thin sheet. The light contains two fractions having different wave lengths from each other. When the light has been reflected on the thin sheet, first and second image pickup means receive one and the other of the aforesaid two fractions respectively. In order to be free of the adverse effect of characters, etc. printed on the reverse side of the thin sheet and seen therethrough on the obverse side, an signal processing system is operable such that image information on the obverse side of the thin sheet alone is extracted from image data outputted from the first and second image pickup means respectively.
Abstract:
An image reader for reading book-like documents placed on a document platen in a face upward condition, said image reader comprises a shading reference panel provided beside the document platen which is white in color and of uniform density, an image reading device which reads the document platen on which the book-like document is placed and the shading reference panel, and outputs image data, a height detector which detects a height distribution of the book-like document, an illuminance detector which detects an illuminance irregularity in accordance with the image data corresponding to the shading reference panel, calculator which calculates shading correction data in accordance with the height distribution and the illuminance irregularity on the shading reference panel and, shading corrector which corrects the illuminance irregularity of the image data corresponding to the book-like document in accordance with the shading correction data.
Abstract:
An image reading apparatus having a function for rectifying an image distortion caused by a curvature of a document surface, wherein the image distortion is rectified by duplicating image data that is a line of pixels in accordance with a varied amount of heights of a document surface, and a data conversion that is a image processing procedure in which the number of bits for pixels is reduced, is executed for the rectified image data. Data conversion elements whose number is the same as the maximum duplicated number "N", are arranged in a data conversion device, and the image data of a line to be duplicated arc input to the data conversion elements whose number is the same as duplicated number "n" of the line (n.ltoreq.N), and then, n-line image data which is processed in n data conversion elements, are stored in a memory. Thereby, reducing a memory capacity needed for the distortion rectification can be achieved without lowering picture quality.
Abstract:
The present invention relates to an image reader well suited for reading for reading bound documents such books and magazines, the image reader comprises a document table to support a document to be read, an image sensor to convert a document image to electrical signals, and a signal processing unit to quantize and output said electrical signals to external devices. The signal processing unit is constructed so as to be capable of reading the edge surfaces in a direction perpendicular to the lateral direction of a document in an open-faced state and is provided with a size detector to detect the document edge positions on bilateral sides of the open-faced document in a lateral direction, a page size calculator to calculate the length of one page in a lateral direction of said open-faced document based on the read information of the edge surfaces and document edge position detected by said document size detector, and output range setting device to set the image output range in accordance with the length of one page calculated by the page size calculator.
Abstract:
An image reading apparatus which reads document surfaces of open book-like documents placed on a document platen in a face upward condition, the image reading apparatus comprises; a first detector which detects a height distribution of a document surface in a main scanning direction, a second detector which detects a height distribution of the document surface in a sub-scanning direction, and a direction discrimination device for discriminating whether a placement direction of the document is a main scanning direction or a sub-scanning direction based on the height distributions.
Abstract:
An image reading apparatus for book-like document includes a height detecting device which detects a height of the document, a luminance detecting device which detects a luminance of a background portion of the document image, a gloss calculating device which calculates gloss of a surface of the document in accordance with the height and the luminance, a luminance calculating device which calculates luminance corresponding to a background portion of the document image in accordance with the gloss and the height, a selecting device which selects either the detected luminance or the calculated luminance, and a density correcting means for correcting a density of the image data in accordance with said selected luminance.
Abstract:
An image reading apparatus which reads out a document placed face-up by scanning optically from above the document, having a document change detection means, and when a document is not changed, a reproducted image density is controlled by using a previous result of the document ground brightness detection without detecting newly. Further, an image reading section is arranged on a document table which a bookform document is placed upward and an auto-document feeding unit for conveying a sheetform document is provided, where by a conveyed sheetform document is read out by a sensor at a fixed focal position.
Abstract:
An image reading apparatus which reads book-like documents placed on a document platen in a face upward condition. A first detector detects the height of the document surface by the shape of a side surface of the document, and a second detector detects the height of the document by the shape of the document surface. A discrimination device detects abnormal height data detected by the detectors, and distortion of image data output from an imaging device is corrected using height data determined to have no abnormality.
Abstract:
Long decay phosphors are disclosed that are comprised of rare-earth activated divalent titanates. In particular, the long decay phosphors are comprised of(Ca.sub.(1-a-b) Pr.sub.a M.sub.b)O.TiO.sub.2wherein0.00001.ltoreq.a.ltoreq.0.1 and0.0.ltoreq.b.ltoreq.0.3and M is Zn and/or Mg.