A method for protecting a chuck membrane in a reactive ion etcher during plasma processing is described. Specifically, the apparatus is made up of a plurality of open ended channels collectively forming a matrix. The mounting portion of the radio has a locking ring on which a plurality of radio locking tabs are located at equally spaced positions. The anchor includes second update times information representing the number of times that the defect list has been updated. By drawing together elements of the chuck, a mechanical gearing advantage may be realized to add additional torque. According to the circuit and method, the self light-emitting display device can be driven more stably and with a higher efficiency by adjusting the number of used bits and luminance of respective color components in accordance with a luminance change of an external light and keeping a constant contrast ratio irrespective of the adjustment of the bit numbers.