Eastman-kodak Company

Global Oled Technology LLC

Michael William Mattern

Paul John Fleming

Carl Michael Petruzelli

Ronald S Cok

John W Hamer

Kenneth D Kieffer

Jeremy K Chung

Michael John Donahue

Tracy Fox

Edward Michael Kelly

A method of making a display includes providing a display substrate having a plurality of control electrodes in a display area; locating a plurality of chiplets responsive to a controller to provide current to the control electrodes, each chiplet having a separate substrate, at least one pixel connection pad electrically connected to a control electrode, and one or more test light emitters formed in the chiplet responsive to the current provided on the control electrodes to emit light; controlling the chiplets to pass current through one or more of the test light emitters formed in the chiplet to emit light; detecting the light emitted by the test light emitters to determine faulty chiplets or chiplet interconnections; replacing or repairing the faulty chiplets or chiplet interconnections; and forming an organic light emitting diode over the substrate in the display area connected to the control electrodes.

Optically testing chiplets in display device

A driver chip for use in an LED or other multi-element recording printhead includes a plurality of current driver channels. Data for determining recording durations for each of the current driver channels is provided on a data bus. A token bit is shifted through a shift register in association with image data to be latched by registers corresponding to a specific driver channel. The driver chip is operational in different recording resolution modes so that it may be connected to recording arrays of different resolutions. When operational in other than its highest or higher resolution, a by-pass signal is generated causing the token bit to by-pass certain stages of the shift register.

Driver IC configurable for recording in multiple resolutions printhead

A non-impact printhead having a plurality of driver IC chips and and a plurality of recording elements such as LEDs. Each driver IC chip includes a plurality of current-carrying channels that are operative for carrying current to respective recording elements on the printhead and a control for controlling operation of the driver. The control includes a circuit that provides a test circuit interface which includes (a) a test access port for input of update command signals and clock inputs to the test circuit; (b) a test data input terminal for inputting test data and control data into the chip; (c) a plurality of registers connected to the test data input terminal with at least one of the registers storing control data for controlling operation of the driver; (d) a test data output terminal for outputting test data and control data from the chip to an adjacent chip; and (e) a selector connected to the registers and the test data output terminal for selecting test and control data for output from the test data output terminal.

Led printhead and driver chip for use therewith having boundary scan

In an LED printhead or the like, a plurality of LED arrays are arranged in a row. Opposite the LED arrays are driver IC chips providing current in respective current driving channels to respective LEDS. Current to an LED for recording of a pixel will be provided for say a duration related to a multibit image data signal. A data bus is provided for carrying the data signals. The data signals are latched in respective data registers associated with each current driving channel. A token bit shift register is provided for identifying a respective data register for latching of the multibit image data signal presently on the data bus. A direction of shifting of the token bit is determined through automatic self-sensing of the token bit itself as the token bit is moved from a boundary scan register that forms a part of a boundary scan test architecture.

Driver IC with automatic token direction self-sensing circuitry

A non-impact printhead for use in recording on a recording medium includes a plurality of energizable recording elements such as LED's. Integrated circuit driver chips are provided that include a current mirror having a master circuit for generating a reference current and a plurality of slave circuits for providing respective driver currents to the recording elements selected for energization. A transistor switch is in series with a respective recording element and switchable from one state to another in response to a signal at its control electrode. An enabling circuit operating upon the control electrode switches the transistor switch to allow current to be selectively provided to the recording element for a predetermined period of time. Each of the slave circuits include an additional slave circuit which provides a current path for facilitating changing of the signal at the control electrode from on voltage level to another such as by allowing a capacitive charge at the control electrode to dissipate. A reference voltage is generated for driving the recording elements. A second transistor in series with the transistor switch establishes a first voltage signal that is input to one electrode of the transistor switch. The first voltage signal varies with variations in the reference voltage. The additional slave circuit generates a voltage signal at the control electrode of the transistor switch means that varies with the reference voltage. Thus, variations in the reference voltage will not substantially affect the level of current driven to the LED's during recording of a pixel.

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Hamlin, NY, United States of America

Michael William Mattern