| 摘要 |
An optical pickup adopting a multi-coated polarization holographic optical element (HOE). The optical pickup has a light source, an objective lens for converging light emitted from the light source on a recording medium, a holographic optical element (HOE) arranged along an optical path between the light source and the objective lens, for changing traveling of the incident light, a phase delay plate arranged between the HOE and the recording medium, for changing a polarization direction of the incident light, and a photodetector for receiving the light reflected by the recording medium, wherein the HOE includes a polarization beam splitter for transmitting one polarized light component of the incident light and reflecting the other polarized light component thereof; and a reflection member having a hologram pattern for diffracting the light passed through the polarization beam splitter, for reflecting the incident light, and wherein the HOE is arranged at an angle between the light source and the phase delay plate. Also, when a transmission-type HOE is adopted, the phase delay plate is arranged at an angle along the optical path between the HOE and the objective lens and includes multiple coating layers for transmitting one polarized light component of the light incident from the light source and reflecting the other polarized light component, and a reflection layer formed on one side of the multiple coating layers, for completely reflecting the incident light. |
