Information recording apparatus

An information recording apparatus for writing information onto an information storage medium using a light beam emitted from a light source, comprising:

• a first detection unit for detecting a power of a light beam emitted from said light source;
• a second detection unit for detecting a non-track condition and an in-focus condition of said light beam relative to said information storage medium;
• a first generation unit for generating a detection signal indicative of a variation in power of the light beam on the basis of a detection signal output from said first detection unit;
• a second generation unit for generating a tracking error signal on the basis of a detection signal output from said second detection unit;
• a third generation unit for generating a focus error signal on the basis of a detection signal output from said second detection unit;
• a first control unit for adjusting the power of the light beam emitted from said light source on the basis of the detection signal generated by said first generation unit;
• a second control unit for performing tracking servo on the basis of the tracking error signal generated by said second generation unit;
• and
• a third control unit for performing focus servo on the basis of the focus error signal generated by said third generation unit, and
• at least one delay device delaying a sample and hold signal which is in sync with information to be written and is to be supplied to a focus and tracking servo system formed from said second and third generation units and said second and third control units, wherein
• said first control unit samples and holds the detection signal generated by said first generation unit, in sync with a timing delayed by a time corresponding to a delay time of said first generation unit, and adjusts the power of said light beam on the basis of the detection signal held,
• said second control unit samples and holds the tracking error signal generated by said second generation unit, in sync with a timing delayed by a time corresponding to a delay time of said second generation unit, and performs said tracking servo on the basis of the tracking error signal held, and
• said third control unit samples and holds the focus error signal generated by said third generation unit, in sync with a timing delayed by a time corresponding to a delay time of said third generation unit, and performs said focus servo on the basis of the focus error signal held.