Patent ID: 7068933

Claim:
A monitoring apparatus to monitor respective output levels of at least a first light source and a second light source in an optical recording device, the first light source being configured to produce a first light beam at a first recording power level suitable for optically recording a first type of recording medium, and the second light source being configured to produce a second light beam at a second recording power level suitable for optically recording a second type of recording medium, with the first recording power level and the second recording power level being different from each other, the monitoring apparatus producing an amplified detection signal representing the monitored output levels for use by the optical recording device to maintain the first light beam at the first recording power level and the second light beam at the second recording power level, respectively, the monitoring apparatus comprising: a light receiving unit to receive, and produce a proportional detection signal in response to, at least one of at least a portion of the first light beam and at least a portion of the second light beam; and an amplification unit having at least a first gain and a second gain, the first gain and the second gain being different from each other, with the amplification unit being configured to receive the detection signal, and to selectively apply to the detection signal one of the first gain and the second gain, to produce the amplified detection signal, the amplified detection signal having a first dynamic range when the first gain is applied to the detection signal resulting from detection of the portion of the first light beam and a second dynamic range when the second gain is applied to the detection signal resulting from detection of the portion of the first light beam, and with the first gain being predetermined such that the first dynamic range is wider than the second dynamic range.