BRIEF DESCRIPTION OF THE DRAWINGS
FIG 1(a) is a diagram showing an example of the relationship between the environmental temperature and the diffraction efficiency, and FIG. 1(b) is a diagram showing an example of the relationship between the wavelength fluctuations and the diffraction efficiency.
FIG. 2(
a) is a drawing showing the light flux converged on the information recording surface of the optical disk OD by the diffraction element DE as viewed in a direction at right angles to the optical axis, and FIG. 2(b) is a diagram showing the light flux converged on the information recording surface of the optical disk OD as viewed in a direction at right angles to the optical axis.
FIG. 3 is an outline configuration diagram of an optical pickup apparatus according to the present preferred embodiment.
FIG. 4 is a diagram showing the light receiving section RB of the monitor detector MD as viewed from the direction of the optical axis.
FIG. 5 is a simulation diagram showing the state of the spot of light converged on the recording surface of an optical disk and the flare.
FIG. 6 is a diagram showing an example of an optical pickup apparatus.