Abstract: Systems and methods are provided for determining registration errors in the cross process direction of a printer. A first straight line is obtained by detecting line centers of a first plurality of dashes in a test pattern. A second straight line is obtained by detecting a line center positions of a second plurality of dashes in the test pattern. A difference between the off-set of the first straight line and the off-set of the second straight line is used in determining registration errors.

Abstract: Systems and methods provide calibration for a linear array sensor. A test pattern having a plurality of lines is used. Comparison between expected and measured spacing between a pair of neighboring lines is used to determine sensor position displacement.

Abstract: A developer apparatus for developing an image, including a sump for storing a quantity of developer material comprised of toner of a first color and carrier material, a donor member for developing the image with toner; an auger for transporting developer material within the sump; a toner concentration sensor for sensing toner concentration in the sump, the toner concentration sensor including a viewing window, in communication with developer material in the sump, an optical sensor for measuring reflected light off the developer material and a cleaning member coacting with the auger to clean the viewing window; and a system for generating a signal indicative of the toner concentration in the sump.

Abstract: Systems and methods are provided for detecting intermittent, weak or missing jets of a printer. The detection is implemented using a test pattern. Detected failed jets may be confirmed using a verification target. A printhead containing nozzles corresponding to detected failed jets may be wiped or purged.

Abstract: Systems and methods are provided for detecting process direction registration errors in a printer. The errors are detected by analyzing a metric of a dash minimum response obtained from a test pattern. The test pattern contains dashes. At least one dash is shifted in the process direction in relation to another dash.

Abstract: Systems and methods are provided for determining registration errors in the cross process direction of a printer. A first straight line is obtained by detecting line centers of a first plurality of dashes in a test pattern. A second straight line is obtained by detecting a line center positions of a second plurality of dashes in the test pattern. A difference between the off-set of the first straight line and the off-set of the second straight line is used in determining registration errors.

Abstract: System and methods are provided for detecting color separation misalignment in raster optical scanners. A dash minimum response curve is obtained from a plurality of minimal responses sensed from a plurality of dashes in a test pattern. The frequency of the dash minimum response curve a is used to detect skew or bow, depending on whether the frequency is a constant or a variable.

Abstract: A device to measure toner concentration can include a selector that selects a type of developer material to be measured and a sensor that detects an amount of light reflected off a developer material. A controller within the device can determine a value corresponding to a toner concentration of the developer material based on the amount of light detected by the sensor.

Abstract: Systems and methods provide calibration for a linear array sensor. A test pattern having a plurality of lines is used. Comparison between expected and measured spacing between a pair of neighboring lines is used to determine sensor position displacement.