Abstract: An electrophoretic display has a grid cathode matrix arrangement consisting of a first plurality of parallel conductive lines insulated from a second plurality of parallel conductive lines transverse to said first plurality. Located with respect to the grid and cathode lines are first and second anode structures. The first anode is remote from the second with the second anode overlying the grid lines of the display and insulated therefrom. The second anode is biased to implement typical HOLD and ERASE modes independent of the first anode.

Abstract: An electrophoretic display includes a plurality of intersecting grid and cathode lines which are spaced one from the other by means of an insulating material. The grid and cathode lines are associated with an anode electrode which constitutes a planar glass plate having deposited thereon a thin layer of ITO or a similar metal. Interposed between the cathode and grid structure and the anode plate is a mesh electrode which is relatively of the same size as the anode plate. Control voltages are applied to the mesh structure and the anode electrode to further control particle propagation. The conventional anode structure may be entirely replaced with the mesh-like structure to provide an electrophoretic display which can be optimumly illuminated by back lighting.

Abstract: Driver circuit chip mounting techniques for use in the fabrication of monolithinc flat panel displays are disclosed in accordance with the teachings of the present invention. According to a preferred embodiment, a driver circuit having a spot of optical cement is precisely positioned within a location of metalized, grouped and patterned row or column conductors. Thereafter collimated ultraviolet light is imaged through the display onto the rear of the driver circuit until the optical cement has become sufficiently tacky to permit the display to be inverted whereupon collimated ultraviolet light may be directly applied to complete the full curing of the optical cements.

Abstract: There is disclosed a method to enable one to deposit a thin layer of chrome to a thicker layer of an organic polymer. The surface of the organic polymer has a thin layer of silicon dioxide deposited thereon and then a thicker layer of chrome is sputtered onto said layer of silicon dioxide. This enables one to pattern and to wire bond to the chrome layer while avoiding stress cracks in the chrome as provided by prior art techniques.

Abstract: There is described a method and apparatus for driving an electrophoretic display during a writing mode. During this mode the cathodes that are not being written into are pulsed in regard to the pulsing of a grid that is being written into. The grid that is being written into is associated with a cathode line which line is caused to assume a writing mode for a longer duration than the pulse applied to the writing grid. At the same time cathode lines which are not being written into are pulsed for a time duration equivalent to the time duration of the writing grid pulse. By pulsing the electrodes in the manner described above, one increases the writing speed of the electrophoretic display while maintaining a bright uniform background for the display.

Abstract: There is disclosed a multi-mode power supply for biasing an electrophoretic display and particularly for biasing the anode electrode of such a display. The supply contains first and second supply means each of which can operate as a constant voltage or constant current supply. The first and second supplies are respectively coupled to the anode electrode of the electrophoretic display so that during the Write Mode the display is operated with a constant current at a first polarity and operates with a constant current at a second polarity during the Erase Mode. Additional modes are shown where AC voltages are applied to the anode electrode either directly as in the case of a Slow Erase Mode or via a capacitor in the case of a Time 60 Cycle Mode for a given time period. In these modes the supplies are operated as constant voltage sources to enable suitable magnitude voltages to be applied to the anode electrode in order to provide optimum operating conditions for the electrophoretic display.

Abstract: Driver circuit chip mounting techniques for use in the fabrication of monolithic flat panel displays are disclosed in accordance with the teachings of the present invention. According to a preferred embodiment, a driver circuit having a spot of optical cement is precisely positioned within a location of metalized, grouped and patterned row or column conductors. Thereafter collimated ultraviolet light is imaged through the display onto the rear of the driver circuit until the optical cement has become sufficiently tacky to permit the display to be inverted whereupon collimated ultraviolet light may be directly applied to complete the full curing of the optical cements.

Abstract: There is disclosed a method which minimizes bubble growth during electrophoretic cell operation. The method involves exposing the electrophoretic suspension to an ultrasonic probe at a given frequency and amplitude and for a suitable time period just prior to pouring the suspension into the electrophoretic display. Exposure to the ultrasonic probe minimizes bubble growth during actual cell operation as the probe operates to drive out a significant amount of gas contained in the suspension while further affecting the pigment particle characteristics.

Abstract: There is disclosed a telephone subset which incorporates a high resolution electrophoretic display on the surface of a subset housing. The telephone subset includes a microprocessor which operates under the control of a mode selector. In this manner the display is employed to generate various keyboard formats and operates in conjunction with a position sensitive overlay to enable a subscriber to place telephone calls in a conventional manner when the keyboard display is implemented on the electrophoretic display. The telephone subset in conjunction with various subset buttons which control the mode selector is capable of operating in different modes. Due to the high resolution and large capacity of the display one can now present pages of stored telephone numbers which essentially enables a user to select any number by the use of a movable cursor and by pressing another subset button can immediately dial that number.

Abstract: Methods for fabricating monolithic flat panel displays together with the resulting display are disclosed in accordance with the teachings of the present invention. According to the invention the end portions of the row and column conductors of a display panel are metalized, grouped and patterned to accept a driver circuit within the pattern of each group. The driver circuit is then bonded to the panel and each output of the driver circuit to be employed is wire bonded to the patterned conductor portions within the group associated therewith. Inputs to the driver circuit may also be wire bonded to input conductors provided on the panel to provide an integral one piece structure.

Abstract: Various techniques and apparatus for grey scale operation for an electrophoretic display panel (EPID) are provided. The apparatus includes circuitry with a timing generator which produces a plurality of different time duration output waveforms which are applied to the X and Y drivers associated with the EPID. In this manner by applying a set of voltages for a given short time interval, a display is provided which results in the incomplete removal of pigment from an associated selected pixel. Hence, that pixel appears darker than surrounding pixels but not as dark as the pure dye solution as associated with the display. The amount of pigment removed and hence the darkness of each pixel is a function of the time duration during which appropriate voltages are applied to the rows and columns of the EPID. In this manner the timing generator can cause different pixels as displayed to have different darknesses or grey scale values by varying the time during which the voltage is applied to the display.

Abstract: Methods for fabricating monolithic flat panel displays together with the resulting display are disclosed in accordance with the teachings of the present invention. According to the invention the end portions of the row and column conductors of a display panel are metalized, grouped and patterned to accept a driver circuit within the pattern of each group. The driver circuit is then bonded to the panel and each output of the driver circuit to be employed is wire bonded to the patterned conductor portions within the group associated therewith. Inputs to the driver circuit may also be wire bonded to input conductors provided on the panel to provide an integral one piece structure.

Abstract: There is shown a method and apparatus for operating an electrophoretic display. The display is operated in a first mode where essentially it operates as a display having normal DC voltages applied to its electrodes. During a non-display mode, a suitable alternating voltage of a given frequency and magnitude is AC coupled to the anode electrode of the display for a predetermined time interval to cause pigment particles to settle between the anode and cathode whereby the effective life of said display is increased. The transfer of the display mode to the second mode is afforded by suitable switching circuitry.

Abstract: Electrophoretic display panel apparatus having improved alignment and contrast characteristics and methods therefor is provided in accordance with the teachings of the present invention. According to a first aspect of the invention a display panel having a plurality of rows of cathodes and a plurality of perpendicularly disposed grid conductors is provided. Each grid conductor is formed as a plurality of commonly connected parallely disposed lines formed on an insulating tine structure to enable the thickness of each conductor and tine to be adjusted for optimum contrast characteristics and to ensure that the requisite number of intersections are provided between rows and columns even should slight misalignment therebetween occur.

Abstract: There is disclosed an electrophorectic display apparatus which includes a planar transparent member having disposed on a surface a plurality of vertical conductive lines to form a grid of lines in the Y direction. On top of the grid of vertical lines there is disposed a plurality of horizontal lines which are positioned above the vertical lines and insulated therefrom by a thin insulating layer at each of the intersection points. Spaced above the horizontal and vertical line pattern is a conductive plate. The spacing between the conductive plate and the X and Y line patterns is filled with an electrophoretic dispersion containing chargeable dye articles. When a voltage is impressed between the X and Y lines, dye pigment particles which are located in wells or depressions between the X and Y pattern are caused to migrate towards the conductive plate and are deposited upon the conductive layer in accordance with the bias applied to the X and Y line conductors.

Abstract: There is disclosed an electrophoretic display apparatus which includes a planar transparent member having disposed on a surface a plurality of vertical conductive lines to form a grid of lines in the Y direction. On top of the grid of vertical lines there is disposed a plurality of horizontal lines which are positioned above the vertical lines and insulated therefrom by a thin insulating layer at each of the intersection points. Spaced above the horizontal and vertical line pattern is a conductive plate. The space between the conductive plate and the X and Y line patterns is filled with an electrophoretic dispersion containing chargeable pigment particles. When a voltage is impressed between the X and Y lines, pigment particles which are located in wells or depressions between the X and Y pattern are caused to migrate towards the conductive plate and are deposited upon the conductive layer in accordance with the bias applied to the X and Y line conductors.

Abstract: Apparatus is disclosed for connecting to a plurality of closely spaced lines located on a display panel. The panel is positioned in a base plate assembly which serves as a frame for the panel. The base assembly has a plurality of first and second locating pins arranged along a side of the panel with a set of pins positioned with respect to an aperture on said base assembly. A plurality of carrier boards are employed to connect to the closely spaced lines, wherein each board is positioned between associated pins and overlies the aperture. When in this position, contact areas on the underside of the board are forced to contact signal lines which underlie the aperture by means of a conductive coupling strip positioned in each aperture. The top of the carrier board contains output conductors which are connected to the display lines by means of another conductive strip located on the top of the carrier boards and directed through a channel.