| 摘要 |
PURPOSE:To prevent the performance of an optical head from deteriorating by forming a recording medium slide surface which has water resistance and is in almost the same surface shape with the image plane of a condenser lens part on one end surface of a base material, and arranging an end surface of a thin film optical waveguide a constant distance behind the recording medium slide surface. CONSTITUTION:One end surface of the substrate 2b is a cylindrical curved surface, a wear- resisting layer 2c is formed on this end surface to uniform thickness, and the curved surface is used as the slide surface 8 for a recording medium. Further, a low-refractive-index dielectric layer 2a with uniform thickness is formed on a flank of this substrate 2b and this end surface is part of the slide surface 8. Those low-refractive-index dielectric layer 2a, substrate 2b, and wear-resisting layer 2c constitute a base material 2. The thin film optical waveguide 1 equipped with a thin film lens 4, an optical deflecting part 5, and a condenser lens part 6 is provided on the wear-resistance layer 2c of this base material 2 and the end surface on the side of the slide surface 8 is arranged slightly behind the slide surface 8 in parallel to the slide surface 8 to form a luminous flux projection curved end surface 7. Consequently, the luminous flux projection end surface never contacts the recording medium and the performance for recording and reproduction is maintained excellently even when the optical head is used for a long period. |
