Method and apparatus are described for MOS capacitors. A data transmitting apparatus and method computes a RX filter or a TX filter for each user receiver in an improved scheme, selects a codebook correlating with the computed TX filter or the computed RX filter, and transmits an index of the selected TX filter codebook or an index of the selected RX filter codebook to a receiver. In one embodiment, photosensor power control circuitry can maintain the first voltage across the photosensors when a power consumption of the signal sensing circuits is less than 1% of the power consumption of the signal sensing circuits during readout of a signal from the portion of the imaging array. Interference of two or more of the laser light beams generally at the acousto-optic modulator can provide an interfered laser light beam thereof.