Planar International Oy Ltd.

Terho Harju

The invention concerns a method and device for driving an electroluminescence matrix display. According to the method succeeding images are formed on the display (1), whereby to form one image all the row electrodes (r1-r6) of the display are scanned through one by one with a constant voltage, and a column voltage corresponding to the desired instantaneous combination of luminance levels is formed for the column electrodes (c1-c2) in synchronism with the scanning of the row electrodes (r1-r6). According to the invention a voltage corresponding to the average modulation voltage (AV) of the column electrodes (c1-c6) is connected to at least a part of the non-selected row electrodes (r1-r6) to capacitively raise the column electrodes (c1-c6) by the amount of the average modulation level, and only the required column electrodes (c1-c6) are driven to the difference voltage in reference to the average modulation voltage (AV).

Method and device for driving an electroluminescence matrix display

The present invention relates to a pulse generation circuit and drive scheme for row selection pulses in a symmetric control scheme of AC-excited thin-film electroluminescent (ACTFEL) displays. The circuit comprises a supply voltage source for feeding the circuit with the supply voltages, a circuit ground to establish the ground potential, two control inputs for controlling the pulse-generating circuit, an output for routing the row selection pulses to the display acting as the load, and an essentially symmetric circuit with respect to the circuit ground for generating the opposite-polarity row selection pulses.

Growing community of inventors

Lohja, Finland

Terho Harju