| 摘要 |
Chemically-bonded laminated polymer achromatic polarization devices (110), such as circular polarizers, are disclosed for use in optica disc (124) pickup heads. Chemically-bonded laminated polymer achromatic, polarization devices have the benefit of providing stable retardation and optic axis over an extended wavelength range, thereby ensuring orthogonal polarization in double-pass for two or more laser wavelengths. Moreover, the chemically-bonded laminated polymer achromatic polarization devices can be symmetric in construction, such that there is no specific input and output side. This alleviates the need to produce geometries that prohibit inversion of the part when installed in the system. |
