| 摘要 |
<p>An optical device comprises a light source emitting a diverging light beam, a polarization beam splitter for transmitting or reflecting the diverging light depending on the polarized component thereof, a collimator lens for transforming the transmitted diverging light beam into parallel light beam, and an objective lens for focusing the parallel light beam onto an object. The optical device further comprises an optical element disposed between the collimator lens and the objective lens and having a main axis perpendicular to or parallel with the incident plane of the diverging light beam of the polarized beam splitter to cause a phase difference of +90°±15°or -90°±15° between the P-polarized light and S-polarized light. For example, the optical device comprise a quarter wavelength plate having an optical axis perpendicular to or parallel with the incident plane of the diverging light beam of the beam splitter.</p> |
