Abstract: A laser printer for Braille that obviates the need for embossing mechanisms and specialized paper. A laser printer for Braille according to the present teachings increases an amount of a toner that adheres to an area of a paper that corresponds to the Braille element. The increased amount of toner yields a printed Braille element that may be read by touch.

Abstract: A system and method are provided for determining a light output of a light emitting diode (LED) in a scanner. The system includes a processor circuit to execute current control logic to obtain an optimum light output from the LED. The current control logic repeatedly applies increasing or decreasing currents to the LED until a saturation point is identified. This may be accomplished, for example, by comparing two measures of the light output of the LED for two different currents applied to the LED. When a difference equaling a predetermined threshold between the two measures is detected, then the saturation point is identified.

Abstract: A laser printer for Braille that obviates the need for embossing mechanisms and specialized paper. A laser printer for Braille according to the present teachings increases an amount of a toner that adheres to an area of a paper that corresponds to the Braille element. The increased amount of toner yields a printed Braille element that may be read by touch.

Abstract: A laser print apparatus includes a memory for storing a multi-bit image including a plurality of pixels. Each pixel is represented by an N-bit value, wherein N is greater than one. A modulation code generator analyzes three adjacent pixels. The three adjacent pixels include a left pixel, a center pixel, and a right pixel. The modulation code generator is configured to generate a pulse width value based on the value of the center pixel, and a justification value based on the values of the left pixel and the right pixel. A laser print engine forms an output pixel on media based on the pulse width value and the justification value.

Abstract: When a sensor of a scanning array is identified as “bad” (defective), data from a neighboring “good” sensor is used to determine pixel data nominally associated with the bad sensor. During a calibration procedure, dark-offset and gain values are determined for each sensor to compensate for individual differences between the sensors of the array. These values are entered into a table in memory. During scanning of an actual image, the values are used to determine digital image pixel data from the signal data provided by the sensors. The calibration procedure also identifies bad sensors, e.g., sensors that remain on or off, irrespective of the illumination incident to them. Extreme offset and gain values are entered into the table locations associated with the respective sensor. When the extreme values are detected, the signal data for the respective sensor is discarded, and the pixel data associated with the most recently processed good sensor is used as the pixel data associated with the bad sensor.

Abstract: Reproducing sepia tone images. The image is scanned using conventional RGB light and added infrared wavelengths. Using L*a*b* color coordinate system, “L”-channel values are determined by the infrared channel only, and “a” and “b” channels are filled with respective benchmark values that represents the yellow-brown sepia background tone of the original. This new L*a*b* data is converted to appropriate output device color space.

Abstract: A multifunction image-transfer system with printing, scanning, digital copying, and facsimile capabilities detects skew as sheet media is fed. A skew processor digitally skews image data as a function of sheet-feed skew detected by skew detectors. In the context of a scanning operation, an image-bearing document is fed to a scanner device, which generates a digital raster image. A buffer stores portions of the digital image as it is transferred. The image data in the buffer is digital skew-compensated before it is transferred to a host computer. In the context of a printing operation, raster print data is stored in the memory buffer and then skew compensated before the image is printed to the print media. The digital skew compensation allows mechanical tolerances in such systems to be relaxed and system lifetimes to be lengthened since “true” images can result despite moderate media skew.

Abstract: A system and method for minimizing distortion in printed images due to toner explosion receives the incoming image bit stream and monitors the stream for horizontal lines and edges that would be particularly susceptible to toner explosion distortion. When such features are determined, the bit stream is modified to print an outlined area with a fill pattern therein. This decreases the amount of toner used to print the horizontal line or edge. As less toner is required, toner piles transferred to the paper are shorter and, therefore, tend to generate less distortion when toner explosions occur.

Abstract: A laser print apparatus includes a memory for storing a multi-bit image including a plurality of pixels. Each pixel is represented by an N-bit value, wherein N is greater than one. A modulation code generator analyzes three adjacent pixels. The three adjacent pixels include a left pixel, a center pixel, and a right pixel. The modulation code generator is configured to generate a pulse width value based on the value of the center pixel, and a justification value based on the values of the left pixel and the right pixel. A laser print engine forms an output pixel on media based on the pulse width value and the justification value.

Abstract: A system and method in a scanner for acquiring a number of sensor spots to create a digital image therefrom are provided. The system comprises a plurality of light sources positioned to project an amount of light at a scan target. The light sources are preferably red, blue, and green. The system also includes a contact image sensor positioned to receive an amount of reflected light from the scan target. The contact image sensor includes a number of sensors arranged in a nonlinear pattern. The scan target is moved relative to the contact image sensor or vice versa during the scan operation using suitable apparatus. The light sources are alternatively illuminated to obtain sensor spots from the scan target via the sensors. The sensor spots are stored in memory and an image is generated therefrom.

Abstract: An image forming device having a fast draft mode accomplished by speeding up the media through the image forming device but not changing the image data rate. The image data is scaled to compensate for the increased media speed. The image data may also undergo enhancement processes to increase the quality of the printed image.

Abstract: A system and method are provided to control an acquisition of a number of pixels in a scanning system. In one embodiment, the system includes an interface circuit with a multiplexer to route at least one color component of one of a number of pixels from a sensor to a register. In another embodiment, the system includes at least three registers to receive a color component associated with one of a number of pixels from a sensor, where at least one of the color components is acquired by a multiplexer having a number of inputs. For both embodiments, logic is included that controls the acquisition of various color components, where color components are acquired in random patterns and/or only a predetermined number of the total color components are acquired to reduce an amount of time necessary to scan a document and to eliminate the problem of color artifact.

Abstract: A system and method are provided for calibrating an output from a sensor array in a scanner. The system comprises a processor circuit having a processor and a memory. Stored on the memory and executable by the processor is the scanner calibration logic. The scanner calibration logic comprises logic for determining a minimum dark value for the sensor array, and logic for determining an optimum exposure time of a number of light sources associated with the sensor array. The scanner calibration logic also includes logic for determining a maximum white value for the sensor array at the exposure time, and logic for setting an analog offset based upon the minimum dark value. The scanner calibration logic further comprises logic for setting an analog gain associated with the sensor array based on a sensor output range from the minimum dark value to a maximum white value.

Abstract: The present invention is directed to a system and methodology in which the stepper motor (or a DC motor/encoder combination) of an optical scanning device is replaced by a DC motor which receives feedback information from an extended photodetector used in the scanner, or a proximately close second photodetector. The photodetector of current scanners may be extended (or a second photodetector may be incorporated) to read a margin marking located on, or attached to, the scanner body and the resolution of the extended portion, or separate photodetector, may be increased to accurately capture positioning information. The photodetector of the present invention detects the margin marking, typically located outside of the document scanning area, to determine positional information which is used by the processor to accurately determine position.

Abstract: An imaging system scans a color original and provides a signal with limited chromaticity for use by a print engine or a display. A light source illuminates the original with primary color intensities, for example 21% red, 72% green, and 7% blue. A sensor integrates the reflected intensities to provide a luminance signal. Matrix multiplication to convert to luminance is avoided. In a variation, illumination is provided with 6/19 red, 9/19 green, and 4/19 blue to provide a gray scale image of, for example, business graphics. Such an image has distinguishable variation for colors of equal lightness (L*).

Abstract: Reproducing sepia tone images. The image is scanned using conventional RGB light and added infrared wavelengths. Using L*a*b* color coordinate system, “L”-channel values are determined by the infrared channel only, and “a” and “b” channels are filled with respective benchmark values that represents the yellow-brown sepia background tone of the original. This new L*a*b* data is converted to appropriate output device color space.

Abstract: The present invention is directed to a system and methodology in which the stepper motor (or a DC motor/encoder combination) of an optical scanning device is replaced by a DC motor which receives feedback information from an extended photodetector used in the scanner, or a proximately close second photodetector. The photodetector of current scanners may be extended (or a second photodetector may be incorporated) to read a margin marking located on, or attached to, the scanner body and the resolution of the extended portion, or separate photodetector, may be increased to accurately capture positioning information. The photodetector of the present invention detects the margin marking, typically located outside of the document scanning area, to determine positional information which is used by the processor to accurately determine position.

Abstract: A system and method are provided for calibrating an output from a sensor array in a scanner. The system comprises a processor circuit having a processor and a memory. Stored on the memory and executable by the processor is the scanner calibration logic. The scanner calibration logic comprises logic for determining a minimum dark value for the sensor array, and logic for determining an optimum exposure time of a number of light sources associated with the sensor array. The scanner calibration logic also includes logic for determining a maximum white value for the sensor array at the exposure time, and logic for setting an analog offset based upon the minimum dark value. The scanner calibration logic further comprises logic for setting an analog gain associated with the sensor array based on a sensor output range from the minimum dark value to a maximum white value.

Abstract: A system and method are provided for determining a light output of a light emitting diode (LED) in a scanner. The system includes a processor circuit to execute current control logic to obtain an optimum light output from the LED. The current control logic repeatedly applies increasing or decreasing currents to the LED until a saturation point is identified. This may be accomplished, for example, by comparing two measures of the light output of the LED for two different currents applied to the LED. When a difference equaling a predetermined threshold between the two measures is detected, then the saturation point is identified.

Abstract: An image forming device having a fast draft mode accomplished by speeding up the media through the image forming device but not changing the image data rate. The image data is scaled to compensate for the increased media speed. The image data may also undergo enhancement processes to increase the quality of the printed image.