OPTICAL HEAD AND DISK DEVICE

PROBLEM TO BE SOLVED: To provide a small and lightweight optical head that enables high recording density to be realized, and also to provide a disk device that has the ability of showing high-speed recording/reproduction and high-volume recording density. SOLUTION: This optical head 1 is composed of a semiconductor laser 2, collimator lens 4, polarizing beam splitter 11, 1/4 wavelength plate 12, turn-back mirror 6, objective lens 5, and a transparent converging medium 7. The transparent converging medium 7 is structured, so that adjacent planes are joined to each other directly or via spacers 15b, 15e and a prism 15c, and is mounted on a floating slider 8 via a spacer 15d. A distance from the semiconductor laser 2 to the transparent converging medium 7 is minimized, enabling the optical head to have small size and light weight. An optical spot 9a, which is formed on the area 7b to be converged of the transparent converging medium 7, is used for recording/reproduction for a disk 10, thereby enabling realization of high recording density.