| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical element that is compatible with at least two optical disks and can improve temperature characteristics, and to provide an optical pickup device thereof. <P>SOLUTION: The optical element is used for an optical pickup device for reproducing and/or recording information by using luminous flux with a wavelength of λ1 (370 nm≤λ1≤440 nm) to a first optical disk and by using luminous flux with a wavelength of λ2 (1.5×λ1≤λ2≤1.7×λ1) to the second optical disk. Each luminous flux with a wavelength of λ1 and a wavelength of λ2 passes through the optical element, and the optical element is made of resin, the resin contains at least a base material A and an inorganic fine particle B in which the temperature dependency dn/dt of a refractive index is in the opposite sign to that of the base material A, and the following expression is satisfied: ¾dn/dt¾≤8.0×10<SP>-5</SP>[°C<SP>-1</SP>]. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
