Gain controlling apparatus and method, information reproducing apparatus and method, and information recording apparatus and method

摘要

A gain controlling apparatus is provided with: an adjusting device (6, 7, 8) for adjusting a gain of a generation signal, which is generated on the basis of a light reception signal obtained by receiving a reflection light of a light beam from an information recording medium (1); and a detecting device (21, 14, 16) for detecting whether or not the generation signal is generated and outputting a detection signal when the generation signal is generated. The gain controlling apparatus is also provided with a controlling device (18) for controlling the adjusting device to increase the gain by a predetermined value set in advance when the detection signal is not outputted by the detecting device.