In order to create a clamping mechanism for an adjustable steering column of a motor vehicle, the clamping mechanism is provided with a clamping device and with an electrical actuator, which drives a clamping element that may be moved between a clamped position and an unclamped position. The pixel sensor cell approximately doubles the available signal for a given quanta of light. Four embodiments of an electrode apparatus include a flexible ring and an electrically conductive section having a first end coupled to and extending from the flexible ring, and an intermediate portion extending through a hole in the flexible ring.