| 摘要 |
An original document (10) to be reproduced, bearing coloured images, is placed on a fixed transparent exposure surface (12) beneath which moves (left to right) a reading and printing carriage (16) on which there is mounted an optical system (26-30) which scans successive strips of the original and directs light rays which are reflected from the original to an image converter (32) comprising dichroic filters which separate three primary colour bands, with a high level of optical efficiency. The dichroic filters pass the colour bands to three optical-electrical image converters mounted on the carriage. Also mounted on the carriage is a print device (70) comprising groups of ink jet print elements (72) for printing on a sheet of paper (73) with inks of different colours. The sheet of paper is supported by an insulating belt to which the paper adheres by an electrostatic effect. During the printing operation the reading and printing carriage (16) advances with a stepping motion while the sheet of paper is caused to oscillate in a direction perpendicular to the movement of the carriage in such a way as to produce printing of series-parallel type. During each half-oscillation of the paper, a line of dots of the image to be reproduced is printed while the paper is stationary. An electronic circuit provides for real-time processing of the signals produced by the converters for activating the print elements. At the end of the printing operation the print elements are moved into a parking station where they are cleaned by means of suction. |
