| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical pickup apparatus having compatibility that can correct a plurality of astigmatisms occurring in a condensing spot by an astigmatic differences that a plurality of light sources have and a manufacturing error in an optical element. <P>SOLUTION: In the optical pickup apparatus having compatibility using wavelengths λ1, λ2, a condensing optical system comprises a common correction optical element arranged in a light path, where luminous flux having the wavelengths λ1, λ2 commonly passes, and an exclusive correction optical element arranged in the light path, where only the luminous flux having the wavelengths λ1 or λ2 passes. Then, when astigmatism at the condensing spot formed by the luminous flux having the wavelengths λ1, λ2 for passing optical elements other than the common correction optical element and the exclusive correction optical element in the plurality of optical elements for composing the condensing optical system is set to be first and second astigmatism, the common correction optical element and the exclusive correction optical element give specific astigmatism to the luminous flux having the wavelengths λ1 and/or λ2 passing through each optical element to correct the first and second astigmatism. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
