Xerox Corporation

Fred F Hubble, Iii

James P Martin

Tonya L Love

Joel A Kubby

Stanley John Wallace

Michael D Borton

Alan J Werner, Jr

Eric Peeters

R Enrique Viturro

Kenneth Russell Ossman

Daniel A Robbins

Lalit Keshav Mestha

Lingappa K Mestha

Ralph A Shoemaker

Daniel W Costanza

Steven J Dietl

Michael Carlotta

Gary Walker Skinner

Edward A Powers

Kenneth W Altfather

Donald M Stevens

Theresa K Mattioli

David Kalman Biegelsen

Jeffrey J Folkins

Warren Bruce Jackson

Robert Arthur Sprague

Yao Rong Wang

Raj B Apte

Robert Michael Lofthus

Jagdish C Tandon

Mark A Scheuer

Michael Robert Furst

Thomas J Hammond

Michael G Swales

Lars-Erik Swartz

Raphael F Bov, Jr

Nicholas M Soures

James G Chase

Gerald Abowitz

Michael E Weber

Andrew M Strauch

John B Tasseff, Ii

Robert P Loce

Patrick Yasuo Maeda

William J Nowak

Robert P Siegel

Kristine A German

Steven C Hart

David G Anderson

Moritz Patrick Wagner

Kevin Michael Carolan

Jerry Floyd Adams

Robert E Grace

Mehrdad Zomorrodi

John E Courtney

Kenneth J Mihalyov

Eric Jackson

Li-Fung Cheung

Alfred J Claflin, Jr

Paul W Eakin

Robert E Crumrine

Jean W Laing

Steven L Aurand

Edward T Hinton

Dennis M Diehl

John M Mitchell, Jr

Peter P White

Randolph H Bullock

Thomas R Scheib

Virginia R Nichols

Virginia N MacDonald

G Peter Floridio

Kenneth I Chan

To determine the spectra of objects that have different degrees of fluorescence, a plurality of reference databases are provided, each reference database being suited to a different degree of fluorescence. A most appropriate one of the reference databases is selected based on a predicted degree of fluorescence of an object for which a reflectance spectrum is to be determined. The prediction of the degree of fluorescence may be based on user input, or may be predicted by using a priori information, such as a priori knowledge of media types.

Systems and methods for selecting a reference database for determining a spectrum of an object based on fluorescence of the object

An LED spectrophtometer device for determining an aspect of the color of an object may include: a visible spectrophotometer comprising a plurality of light emitting diodes that emit light in the visible spectrum onto the object; at least one detector for detecting said light after being directed onto the object and for generating an output; and a UV light emitting diode assembly that emits light in the near ultraviolet spectrum and communicates with at least one detector for generating an output. The device may further include a processor that combines the outputs of the at least one detector of the visible spectrophotometer and the at least one detector in communication with the UV light emitting diode assembly.

Systems and methods for augmenting spectral range of an LED spectrophotometer

An improved and lower cost color spectrophotometer, especially suitable for an on-line color printer color control system, in which plural different spectra LEDs sequentially perpendicularly illuminate a common and substantially circularly illuminated color test area, which may be variably spaced and variably oriented relative to the spectrophotometer, through a common central lens system, and also the reflected illumination therefrom may be measured at 45 degrees thereto by averaging the outputs of photodetectors spaced around that circularly illuminated color test area, to provide reduced sensitivity to the variable angular or azimuthal orientation of the color test area relative to the spectrophotometer, and which photodetectors may be so illuminated by 1:1 optics for spatial insensitivity.

Angular, azimuthal and displacement insensitive spectrophotometer for color printer color control systems

An electrostatic type voltmeter for measuring the potential on a surface, the voltmeter including a probe; a support for supporting the probe in spaced relationship with the surface, the probe having a plurality of spacing element sites thereon for measuring a distance between each of the plurality of spacing element sites and a corresponding area on the surface opposite of each of the plurality of spacing element sites; a plurality of electrostatic element sites, intermixed and adjacent to the plurality of spacing element sites on the probe, for measuring a voltage between each of the plurality of spacing element sites and an area on the surface adjacent to the corresponding area opposite of each of the plurality of spacing element sites. A processor for compensating an output signal of the probe in response to the measurements received from the plurality of spacing element sites and the plurality of electrostatic element sites.

Spacing compensating electrostatic voltmeter

A device independent color control server and control methods provide color consistency services and improve consistent color document appearance between any number of connected color image forming devices and/or color display monitors on a distributed network.

Systems and methods for device independent color control to achieve accurate color proofing and reproduction

A sheet curl measurement system and method and an automatic sheet decurling system controlled thereby for the printed paper sheets output of printer. The sheet curl may be remotely sensed without contacting or interfering with the motion of the sheets in their normal sheet path, using a simple but accurate optical sheet curl sensor operating on a portion of the moving sheet at an angle thereto and perpendicularly thereto, with displacement insensitive optics, in both an angular direction substantially parallel to the sheet movement direction and an angular direction substantially transverse to the sheet movement direction, with ratioing of the two output signals.

Lead edge paper curl sensor

A color spectrophotometer incorporating a low cost commercial imaging chip, which normally forms part of a document imaging bar used for imaging documents in scanners, etc., having multiple photo-sites with three different rows of color filters. Each chip is mounted on the optical axis of an imaging lens system, in the image plane of that lens system, to image the reflected illumination from an illuminated color test target area on the chip. The optical axis of the imaging lens system is oriented at 45&deg; to the illuminated color test patches, and the photodetector chip is physically mounted perpendicular to the plane of the illuminated color test patches. Respective photo-sensor chips and associated 1:1 optics may be mounted on opposing sides of the spectrophotometer physically oriented at 90&deg; to the test target area plane receiving the reflected light from the test target optically oriented at 45&deg; to the illuminated test target.

Color image bar based spectrophotometer photodetector optical orientation

In a color analysis method in which sheets with multiple different color printed test patches are moved relative to a color analyzing spectrophotometer, and in which fiducial marks are printed adjacent to respective test patches and optically detected by a fiducial mark detector to provide a triggering system for the respective test patch analysis, there is provided automatic diagnostic testing of the spectrophotometer and the fiducial mark triggering system, including automatically generating special test sheets, some of which may include test areas of varying density black.

Diagnostics for color printer on-line spectrophotometer control system

An apparatus for correcting beam-to-beam spacing error on an image plane of a photoreceptor includes a controller which generates beam-to-beam spacing error corrections signals, a plurality of optical elements, each of which is adjustable and responsive to beam-to-beam spacing error correction signal and a gray level measurement device. The controller performs the beam-to-beam spacing error correction analysis, determining whether or not a correction is necessary, and if so, which optical element to adjust and the magnitude of adjustment. Enhanced toner area coverage sensors are used to detect the gray level of a toned area of raster scan line patterns at various locations across the photoreceptor image plane. By repeatedly evaluating the beam-to-beam spacing error during operation, the apparatus of the invention is able to correct beam-to-beam spacing errors that may develop during operation and does not permit residual errors to persist even after an initial correction has been implemented.

Systems and method for measuring or reducing spacing errors in multiple beam ROS systems

A method is provided for measuring the color of irregular surface materials, including textiles which may provide dissimilar color measurements from different viewing angles, by illuminating a sampling area of the irregular surface material approximately perpendicularly thereto and measuring the color reflected from that area at a substantial angle, preferably about 45 degrees, with a plurality of separate photodetectors arrayed circularly around the illuminated sampling area of irregular surface material to receive the reflected illumination from substantially opposing directions and at a substantial angle to the illuminated area, for providing a more accurate yet lower cost color measurement system for textiles that can be used easily, quickly, and uncritically in terms of the handling, positioning and orientation of the textile material being tested.

Color measurement of angularly color variant textiles

Color imager bar based spectrophotometer photodetector optical orientation

By using a reconstruction algorithm, based on the spectral characteristics of the illumination source and a color sensing system, a spectral curve reconstruction device converts measurements from a non-fully illuminant populated color sensor into a fully populated spectral curve. This is done using a spectral measurement system model, which may use basis vectors.

System and method for reconstruction of spectral curves using measurements from a color sensor and a spectral measurement system model

A developability sensing system with an optical sensor for measuring the density of imaging material samples on an imaging surface of a printer, with an illumination source and photosensor system for measuring the amount of reflected illumination from the imaging materials. A first lens system and its first photosensor may receive both specularly and diffusely reflected illumination from certain imaging materials. A separate lenslet system is positioned outside of the first lens system. It may comprise one to four spaced apart generally cylindrical lenslets with a central axis generally perpendicular to the imaging material sample and an end surface facing the imaging material sample defined by a segment of a hyperbolic curved surface to form a rotationally symmetrical lens with a hyperbolic cross-section. There are separate photosensors for these lenslets, which are positioned and optically adapted to only receive diffusely reflected light from the imaging material sample, even though reflected illumination from the imaging material sample has both specularly and diffusely reflected illumination from partially specularly reflective imaging materials.

Developability sensor with diffuse and specular optics array

A low ink sensing system is combined with an ink cartridge detection system to enable a more efficient ink jet printer. An ink container which supplies ink to an associated printhead is modified by the incorporation of two light directing elements, in the preferred embodiment, a faceted prism and a roof mirror, into a transparent wall of the container housing. The cartridge, comprising the ink container and associated printhead, is mounted on a scan carriage. Periodically, the carriage is conveyed to a sensing station comprising a pair of light sources and a commonly used photosensor. A first light source is energized and a beam of light is directed to a location where the roof mirror, would be positioned if the cartridge is present. If the cartridge is absent, lack of a reflected return signal is sensed, indicating a cartridge has not been inserted. Print operation is halted until a cartridge is inserted. If a cartridge is properly inserted, the roof mirror returns most of the incident light to the photosensor which generates a signal indicating the presence of the cartridge. A second light source is then energized and directed towards the faceted prism, which is either immersed in ink or exposed to air within the interior of the container. If the latter, light is internally reflected by the prism facets back to the photosensor. If a print operation has been in progress, and the ink level has fallen, the common photosensor detects either a strong or weak redirected light component and initiates a status check and generates appropriate displays of low ink level or out of ink warnings.

Sensing system for detecting presence of an ink container and level of ink therein

Growing community of inventors

Rochester, NY, United States of America

Fred F Hubble, Iii