Cholesteric liquid crystal display

An image-writing device that writes an image in a cholesteric liquid crystal display element forming pixels at intersection portions of scan-electrodes of a scan-electrode group and data-electrodes of a data-electrode group, the device comprising:

• an orthogonal function generating circuit that generates an orthogonal function;
• a scan-voltage composing circuit that generates scan-voltages by level-shifting the orthogonal function, the scan-voltages being sequentially applied to each of plural scan-electrodes of the scan-electrode group;
• and
• a data-voltage composing circuit that generates data-voltages by level-shifting a value obtained by multiplying the orthogonal function by a pixel data value, the data-voltages being applied to the data-electrodes of the data-electrode group.

An image-writing method that writes an image in a cholesteric liquid crystal display element forming pixels at intersection portions of scan-electrodes of a scan-electrode group and data-electrodes of a data-electrode group, the method comprising the steps of:

• sequentially selecting scan-electrodes of the scan-electrode group as a block composed of plural scan-electrodes;
• simultaneously applying corresponding coded drive voltages to the plural scan-electrodes, respectively, in the selected block;
• and
• applying corresponding coded data-voltages to the data-electrodes of the data-electrode group synchronously with the drive voltages.