초록 ▼

A circuit and method for time multiplexing a voltage signal for controlling the color balance of a flat panel display. Within an FED screen, a matrix of rows and columns is provided and emitters are situated within each row-column intersection. Rows are sequentially activated during "row on-time win

A circuit and method for time multiplexing a voltage signal for controlling the color balance of a flat panel display. Within an FED screen, a matrix of rows and columns is provided and emitters are situated within each row-column intersection. Rows are sequentially activated during "row on-time windows" by row drivers and corresponding individual gray scale information (voltages) are driven over the columns by column drivers. When the proper voltage is applied across the cathode and anode of the emitters, electrons are released toward a phosphor spot, e.g., red, green, blue, causing illumination. Within each column driver, the present invention provides selection circuitry for driving a first voltage signal during a first part of the row on-time window and a second voltage during a second part of the row on-time window. The lengths of the first part and second part of the row on-time window can be adjusted for a given color, to adjust the color balance with respect to that color, e.g., red, green or blue. In one embodiment, a shift register is used to divide a digital representation of the first voltage value in half for application during the second part of the row on-time window. In a second embodiment, a multiplexer is used to divide the first voltage value in half for application during the second part. In a third embodiment, the first and second parts of the row on-time window are swapped such that two first parts occur consecutively and two second parts occur consecutively over a period of two row on-time windows. The third embodiment reduces the frequency of voltage change and thereby saves power.

대표청구항 ▼

[ What is claimed is:] [1.] A field emission display device comprising:a plurality of row drivers, each coupled to a respective row line, for driving a row voltage signal over one row line at a time during a row on-time window, wherein a pixel includes intersections of one row line and multiple colu

[ What is claimed is:] [1.] A field emission display device comprising:a plurality of row drivers, each coupled to a respective row line, for driving a row voltage signal over one row line at a time during a row on-time window, wherein a pixel includes intersections of one row line and multiple column lines;a horizontal synchronization clock signal for synchronizing said plurality of row drivers by initiating row on-time windows;a plurality of column drivers of first, second and third colors, each column driver coupled to a respective column line and for time multiplexing thereon a first analog voltage and a second analog voltage, respectively, during a first part and a second part of each row on-time window; andeach column driver comprising a color balancing circuit responsive to a color select signal and for generating said first analog voltage based on a first voltage data and for generating said second analog voltage based on a second voltage data wherein said color balance circuit comprises a shift register for receiving said first voltage data representing said first analog voltage and for generating said second voltage data therefrom responsive to said color select signal, said second voltage data representing said second analog voltage.