Abstract: The area detection method detects an area on an original enclosed with a mark of specific color by the steps of scanning the original by a photosensor, judging whether the number of the mark segment detected by the photosensor in a single scan line is an even or odd number for each scan and detecting the area based on the output of the photosensor in the scan period for which the judgement is made that the number of the detected mark segment is an even number.

Abstract: A method and apparatus for correcting the photoelectric converter of a document reading unit for non-linearities produced by the optics of the system. A test document having no image data thereon is scanned to produce a shade correction signal which is subjected to A/D conversion and stored in a memory. In binary-encoding the picture data of the original, a switch is operated according to the data stored in the memory so as to change a threshold level for the picture signal, whereby digital picture data whose shading has been corrected is obtained. In the case where the picture data of the original are represented by an analog signal, the picture data are also subjected to A/D conversion, and division is carried out with the data stored in the memory being employed as dividends. From the results of such a division, corrected multi-level picture data is obtained.

Abstract: A two-color copying machine performs two scannings of an original to supply image data respecting the original to an image sensor. In one of the scans, a complementary color filter is inserted in the optical path to absorb a particular chromatic color. Achromatic printing is carried out using the image signal generated without the filter, while printing in the chromatic color is carried out using a combined image signal generated with said complementary filter in place.

Abstract: A three-color copying machine is made capable of copying in black, a chromatic color and the complement thereof to improve visual image quality while using only two image sensors. Logic circuitry is used to separate the image signals into printing signals for each color.

Abstract: A picture image position setting apparatus having a linear reading element for obtaining picture information by scanning an original document successively line after line. A position designating cursor is attached slidably in a main scanning direction on a platen at a front end or a rear end portion of an original document scanning region on the platen. The position designating cursor is arranged to be sensed by the linear reading element to distinguish it from other scanned portions. A circuit converts picture image information with respect to the position designating which has been read into positional information in the main scanning direction.

Abstract: A recording and copying device capable of producing multiple copies from an original image using a single readout operation, while simultaneously being capable of reversing the image or shifting the image as desired. A photosensitive belt is provided having a light-shielding layer thereon capable of being fluidized or sublimated by heating. This layer is selectively heated by a thermal recording head, after which heated portions are removed by a transfer belt. The exposed photosensitive portions of the belt are then exposed and developed using toner particles, and the developed image transferred to a recording sheet.

Abstract: A copying machine includes sensors and logic circuitry for determining the size or presence of an original placed thereon. According to the size of the original, the scanning length and the size of the recording medium may be determined.