Hewlett-packard Company

Jerry Yeeming Chung

Richard F Beaufort

Warangkana Tepmongkol

Compensation for pixel aberrations in a laser printer is accomplished by selecting pixels to be augmented, and providing additional optical energy to the selected pixels. In one embodiment, the pixels are selected by selecting pixels in combinations in which required pixel augmentation is indicated. The additional optical energy may be applied at the sub-pixel level so that a threshold of energy depletion on an optical photoreceptor (OPR) is not reached where image development would occur. The energy applied at the sub-pixel level results in enhancement of the selected pixels at an adjacent pixel location.

Dot enhancement for laser imagers

Compensation for pixel aberrations in a laser printer is accomplished by altering pixels in accordance with pixel location. A projection of a scan line is skewed with respect to a line normal to the surface of an optical photoreceptor (OPR), which results in a change in the shape of projected pixels. Selected pixels are augmented in order to adjust their shape. The additional optical energy may be applied at the sub-pixel level so that a threshold of energy depletion on an optical photoreceptor (OPR) is not reached where image development would occur. Alternatively, the additional energy may be applied in a manner which provides additional development to simulate a pixel having a desired width across a scan line. The invention allows a scan line to be produced in which pixels across the scan line are made more uniform.

Adjustment of dot size for laser imagers

Paper processing equipment such as a laser printer uses a plurality of sensors to detect the presence of paper in the paper path of the equipment. In order to provide an appropriate response to different types of malfunctions, a determination of the type of malfunction is made, and in appropriate cases, an attempt is made to self-clear the malfunction. In the case of a paper size error resulting from long size sheets being provided without a corresponding software request, the printer senses a time delay resulting from paper passage of an initial sheet. Pick of a second sheet is delayed for a time period corresponding to long size sheet passage and picks of subsequent sheets are delayed only if the sensed time delay corresponds to the longer length. This paper length information is further used to provide information regarding proper discharge of sheets from the printer.

Growing community of inventors

Meridian, ID, United States of America

Jerry Yeeming Chung