Lexmark International, Inc.

International Business Machines Corporation

Wilson Morgan Routt, Jr

Roger Steven Cannon

Martin Christopher Klement

Daniel Eugene Pawley

Gary Allen Denton

Philip Jerome Heink

Eric Wayne Westerfield

Craig Palmer Bush

Daniel Richard Klemer

David John Mickan

Timothy A Green

Robert L Paterson

Dana Allen Dodds

Christopher Gregory Chee

Scott Stephen Williams

David Wayne Glass

Donald Lee West

Randall A Maddox

Ross B Hooker, Iii

Daniel L Huber

Kurt Matthew Korfhage

John D Armitage, Jr

Danny A VanHook

Joseph Ladd Binford, Iii

Methods and apparatus include improving print quality of a bi-directionally scanning electrophotographic (EP) device, such as a laser printer or copy machine, according to ambient pressure in which operated. A moving galvanometer or oscillator reflects a laser beam to create scan lines of a latent image in opposite directions. A damping of the motion occurs per air density implicated by temperature and pressure, where the pressure changes occurring especially from altitude changes. During use, a drive signal, such as a pulse train, moves the galvanometer or oscillator at or near its resonant frequency. Based on a parameter of the drive signal, such as pulse width, the ambient pressure can be made known. In general, a high-pressure environment requires a relatively longer pulse width to resonate the galvanometer or oscillator in comparison to a shorter pulse width for a low-pressure environment. Corrections to print quality stem from the determined ambient pressure.

Obtaining pressure of an operating environment of a bi-directionally scanning electrophotographic device for implementing corrections per pressure

Obtaining pressure of an operating environment of a bi-directionally scanning electrographic device for implementing corrections per pressure

A toner patch including a toner having a given excitation wavelength and a given emission wavelength may be deposited onto a control surface. Light may be provided onto the toner patch and at least a portion of emitted light may be detected from the toner patch at the given emission wavelength by a detector. Furthermore, an operating parameter may be adjusted based on the detected emitted light.

IR fluorescent toner compositions

A lens has a lens body (), reinforcing extensions () and a clear aperture () surrounded on top and bottom by lens body. The lens is suitable for spot scanning. The lens is made of a water absorbing material, such as most polymers, particularly acrylate polymers. Aluminum sheets as vapor barriers are attached on each side of the lens body. This results in excellent resistance to change or distortion in high humidity environments.

Humidity tolerant scan lens

An optical apparatus compensates for imaging errors associated with the sinusoidal angular scan rate of a light beam reflected from a bidirectional scanning torsion oscillator. The compensation is achieved by a combination of pre-scan optics positioned between the source of the light beam and the scanning torsion oscillator, and post-scan optics positioned between the scanning torsion oscillator and an imaging surface of an imaging device. Based on the optical characteristics of its components, the post-scan optical system causes deflection of the light beam in the scan direction. To compensate for the sinusoidal scan rate, the deflection caused by the post-scan optical system is greater at the opposing edge positions of the imaging surface than at a central position. In this manner, the scan rate of the light beam at the first and second edge positions is substantially equivalent to the scan rate at the central position. The pre-scan optical system directs the light beam onto the reflective surface of the torsion oscillator in a manner that compensates for divergence of the light beam in the scan direction caused by the post-scan optical system.

Optical system for torsion oscillator laser scanning unit

An image scanning apparatus and a torsion oscillator are capable of operating across a dynamic range of possible operating frequencies. The image scanning apparatus uses a light source to produce a light beam, and the oscillator scans the light beam through a scanning pattern. The oscillator includes a plate member having a non-rectangular shape. At least one magnet is disposed on the plate. A surface of the plate member includes a reflective surface for reflecting a light beam. A frame is disposed in a spaced apart relation to a lower surface of the plate member. The frame includes at least one coil configured to induce an electromagnetic force on the at least one magnet to thereby oscillate the reflective surface to a rotational angle of oscillation at an oscillation frequency. The system also includes an imaging surface disposed in the path of the scanning pattern so that the light beam scans across the imaging surface, and a mechanical drive to move the imaging surface. A control system controls electric current provided to the at least one coil to achieve the oscillation.

Stationary coil oscillator scanning system

An image scanning apparatus and a torsion oscillator are capable of operating across a dynamic range of possible operating frequencies. The image scanning apparatus uses a light source to produce a light bean, and the oscillator scans the light beam through a scanning pattern. The oscillator includes a plate member having a non-rectangular shape. At least one magnet is disposed on the plate. A surface of the plate member includes a reflective surface for reflecting a light beam. A frame is disposed in a spaced apart relation to a lower surface of the plate member. The fame includes at least one coil configured to induce an electromagnetic force on the at least one magnet to thereby oscillate the reflective surface to a rotational angle of oscillation at an oscillation frequency. The system also includes an imaging surface disposed in the path of the scanning pattern so that the light beam scans across the imaging surface, and a mechanical drive to move the imaging surface. A control system controls electric current provided to the at least one coil to achieve the oscillation.

A lens has a body ( ), reinforcing extensions ( ) and a clear aperture ( ) surrounded on top and bottom by lens body. The lens is suitable for spot scanning. The lens is made of a water absorbing material, such as most polymers, particularly acrylate polymers. Aluminum sheets as vapor barriers are attached on each side of the lens body. This results in excellent resistance to change or distortion in high humidity environments.

A laser beam sensor assembly in an electrophotographic machine includes a sensor device detecting a position of a laser beam in a process direction. The sensor device has a detection range in the process direction. The sensor device has at least one slot or at least one projection. A fixed structure has an other of the at least one slot and the at least one projection. The at least one slot and the at least one projection coact to allow the sensor device to slide in the process direction to a location such that the laser beam is at a desired position within the detection range of the sensor device.

Method and apparatus for locating the process postion of a scan line in an electrophotographic machine

A toner patch sensor arrangement in an electrophotographic machine includes a substantially hollow chamber having a reflective interior surface, a first opening exposing a toner patch, a second opening and a third opening. A light emitting element emits light onto the toner patch through the first opening and the second opening. A light detecting element receives through the third opening light reflected off of the toner patch such that the reflected light is received only after the light has also reflected off the interior surface of the chamber.

Toner patch sensor with integrating optical collection geometry

The invention relates to an ink level sensing apparatus including an ink cartridge having an ink chamber containing ink and having at least one substantially transparent side panel adjacent the ink chamber. A fluorescent material is disposed in the ink chamber, the fluorescent material being substantially insoluble in the ink and having a specific gravity which is sufficiently lower than the ink to provide an interface between the ink and the fluorescent material. A relatively narrow band light source for emitting light at a first wavelength along a light path through the substantially transparent side panel of the ink cartridge is provided for exciting the fluorescent material. A photosensor for receiving light emitted from a fluorescent material at a second wavelength when the excited fluorescent material crosses the light path is provided, wherein the first and second wavelengths are substantially different. The apparatus provides a means for sensing ink level in an ink cartridge in a reliable relatively inexpensive way.

Ink level sensing device and method therefor

An optical system for light scanning devices in which a beam of light travels from an origin to an object along a light path and has along that path a scan direction and a cross-scan direction. The optical system includes a light source at the origin of the light path, a polygonal reflector located along the light path and having adjacent peripheral mirror surfaces rotatable in the scan direction, and a pre-scan optical sub-system located along the light path between the light source and the polygonal reflector. The pre-scan optical sub-system includes, in order of light travel from the light source, a collimating lens and a pre-scan lens having a convex cylindrical lens entrance surface aligned in the scan direction for converging the light beam in the cross-scan direction, and a convex lens exit surface for converging the light beam in the scan direction. An aperture stop may be provided between the collimating lens and the pre-scan lens to further truncate or reduce the diameter of the collimated beam. The optical system has a post-scan optical sub-system located along the light path between the rotatable polygonal reflector and the object and including a first f-theta lens and a second f-theta lens.

Optical system for light beam scanning

An optical system having a single, monolithic scan element as shown in the drawing in which surface 6 is concave, surface 7 is convex, surface 8 is convex, surface 9 is convex and the circumference of surface 9 is convex, surface 10 is convex, surface 11 is convex, and surface 13 is flat. f-theta correction is made primarily at surfaces 6, 9, 10 and 13. The element is molded from optical grade plastic and provides improved performance, no assembly adjustment, performance enhancement from its complex surfaces, and low cost.

Growing community of inventors

Lexington, KY, United States of America

Wilson Morgan Routt, Jr