| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce a phase difference generated in a laser beam for correcting spherical aberration. <P>SOLUTION: An optical pickup comprises a light source 2 for emitting the laser beam; a group of objective lenses 5 for condensing the laser beam incident via an aperture onto the signal recording surface of an optical disk 11; and a refractive power variable element 6 that is provided near the light source 2 and corrects the spherical aberration by varying refractive power. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
