Lexmark International, Inc.

William Pohl Corbett, Jr

Keith Bryan Hardin

James Howard Ellis

John Bruce Berry

Randal Scott Williamson

Gary Allen Denton

James Ronald Booth

Kelly Ann Killeen

James Paul Drummond

Mike Partington

Robert Michael Tulenko

John Francis Gestomski

A magnetic sensor array device is described that is constructed with multiple single sensor die, diced out of a wafer as a group and packaged in a wafer level package (WLP). The device comprises an array of multi-axis magnetic sensors that can measure the multi-dimensional magnetic field of an arbitrary sized two-dimensional region with high spatial resolution, reduced sensing distance, higher measurement throughput, tolerance to motion, improved temperature measurement, and improved yield when placed on a circuit card comprises part of an authentication system including a physical unclonable function ('PUF'), a substrate, a plurality of magnetized particles randomly dispersed in the substrate, and a PUF reader constructed using one or more of the magnetic sensor array devices wherein the PUF reader measures the magnetic field at multiple locations in close proximity to the magnetized particles. The measured magnetic field data may be compared to previously enrolled data to assess authenticity.

Sensor array for reading a magnetic PUF

A magnetic sensor array device is described that is constructed with multiple sensors integrated on a common silicon die, diced and packaged in a wafer level package (WLP). The device comprises an array of multi-axis magnetic sensors that can measure the multi-dimensional magnetic field of an arbitrary sized two-dimensional region with high spatial resolution, reduced sensing distance, higher measurement throughput, tolerance to motion, improved temperature measurement, and improved yield when placed on a circuit card comprises part of an authentication system including a physical unclonable function ('PUF'), a substrate, a plurality of magnetized particles randomly dispersed in the substrate, and a PUF reader constructed using one or more of the magnetic sensor array devices wherein the PUF reader measures the magnetic field at multiple locations in close proximity to the magnetized particles. The measured magnetic field data may be compared to previously enrolled data to assess authenticity.

A system for use in authentication processes is described comprising a physical unclonable function ('PUF'), a substrate, a plurality of magnetized particles randomly dispersed in the substrate, a PUF reader constructed using multiple discrete magnetometer chips that have magnetic field sensors, placed on a circuit card in an array with a sufficient center to center spacing between sensing elements of adjacent magnetometer chips, wherein the PUF reader measures the magnetic field data at multiple locations in close proximity to the magnetized particles. The measured magnetic field data may be compared to previously enrolled data to assess authenticity.

Magnetometer chip sensor array for reading a magnetic PUF, including a magnetic PUF film or tape, and systems incorporating the reader

An imaging device has a photoconductor with a surface that is selectively discharged by a light from a laser diode to create a latent electrostatic image for attracting toner for transfer to a media. A circuit drives the laser diode. The circuit has a switch for turning on and off the light, a resistor complementary to the laser diode selectively connectable to the switch, and a passive circuit component coupled to the laser diode. The passive circuit component is a delay line, inductor, choke, coiled wire, or ferrite bead is contemplated. It may also typify a length of copper tracing on a printed circuit board that supports the laser diode. The circuit causes an initial overshoot voltage spike in an on voltage pulse that is about 20% or more than the settled on voltage. The voltage spike dampens out in about one-fourth of a total voltage on time of the pulse.

Circuit for driving a light source in imaging device for enhancing quality of isolated pixels

A scanning system for use in an imaging apparatus includes a first light source and a second light source for emitting light beams for generating an image. A driver circuitry has first and second outputs connected to the first and second light sources, respectively, for controlling the first and second light sources. A signal transmitter includes a first interface for communicating a clock signal to the driver circuitry and a second interface for communicating an image information signal to the driver circuitry. During a clock cycle of the clock signal, the driver circuitry captures a first bit information from the image information signal at a rising edge of the clock signal and a second bit information from the image information signal at a falling edge of the clock signal. Thereafter, the driver circuitry drives the first and second light sources based on the first and second bit information captured, respectively.

System and method for controlling multiple light sources of a laser scanning system in an imaging apparatus

A boot validation system and method may be used in a computer system to validate boot code before allowing the computer system to execute the boot code. In particular, a secure hash algorithm may be used to compute a hash value of the boot code and the computed hash value may be compared to a preprogrammed hash value stored in a secure non-volatile device. If the hash values match the boot code may be validated and the system may then be allowed to execute the boot code. Once the boot code is validated, the boot code may be executed to validate other code (e.g., firmware) in the computer system. In an exemplary embodiment, the boot validation systems and method may be used in an imaging device, such as a printer.

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Lexington, KY, United States of America

William Pohl Corbett, Jr