Abstract: A method and system for digitally reproducing an image on a printing plate that includes enhancing gray levels so that plate may be imaged at lower resolutions and therefore higher speed. An image is scanned and a two dimensional array of optical density values. A comparison is made with a screen cell array having a repetitive pattern of a plurality of different screen cells. Each screen cells includes screen comparison values which when arranged in a sequence of increasing values are interleaved with values in a similarly arranged sequence of values from one of the different screen cells of the screen cell array. Pixel comparisons generate a binary value which is used to selectively operate a laser beam to expose microdots on a printing plate.

Abstract: An ink-jet apparatus in which a recorded image is read to provide a image reference signal for comparison with an image recording signal, the resulting comparsion being used as a basis for diagnosing an ink injection state of a recording head nozzles in order to determine and implement an ink injection recovery process.

Abstract: A method for reproducing images using rotated screens, wherein the rotated screens are formed by the replication of a screen tile (ABCD). The screen tile (ABCD) is based on a seed screen cell (11, 17) that is disposed at the desired angle of screen rotation, theta, and is replicated so as to fill the screen tile. Thus, the screen can be generated by replicating the screen tile with respect to the same coordinate system as that identifying addresses for the image data being screened, i.e., without rotating the screen tile. Both the screen tile and the seed screen cell (11, 17) are represented by matrices. Noise (51) can be introduced into process of forming the screen in order to further lessen Moire patterns.

Abstract: A system for efficiently generating on a raster line plotter an image that is made up of a plurality of characters, or other objects, based on an opaque ink model. Information relating to the characters is run length encoded, so as to form tone run records corresponding to the raster lines. The tone run records contain information relating to tone value, starting location, length and screen selection. The information is then processed so as to delete, or overwrite, tone value and screen selection information of the portions of characters that underlie other characters. After the appropriate information has been deleted, the remaining screen selection and tone value information is used to create a halftone image.