COMPATIBLE OPTICAL PICK-UP DEVICE

摘要

PURPOSE: A compatible optical pick-up device is provided to compatibly use a CD-RW(rewritable) and a DVD, etc., by improving a configuration of an optical system to minimize aberration generated in an optical pick-up device. CONSTITUTION: The first optical source(51) emits an optical of first wavelength. The second optical source emits an optical of second wavelength shorter than the first wavelength. An optical track converting unit converts a rout of an incident optical. An object lens(83) focuses the incident optical, which is emitted by the first and second optical sources and passed through the optical tract converting unit, on an optical disk(30). An optical detector(75) receives the optical, which is emitted by the first and second optical sources and reflected on the optical disk(30), and detects an information signal and an error signal. The first beam splitter(57) shifts a track of the optical emitted by the first optical source(51). The second beam splitter(63) shifts a track of the optical emitted by the second optical source. The first collimating lens(54) is disposed on an optical route between the first optical source(51) and the first beam splitter(57), and enables the optical emitted by the first optical source(51) to be focused and thus to be a parallel optical. A grating(55) is disposed on an optical route between the first collimating lens(54) and the first beam splitter(57), and diffracts the incident parallel optical into a 0 optical +- optical. The second collimating lens(63) is disposed on an optical route between the second optical source(61) and the first beam splitter(57), and enables the optical emitted by the second optical source to be focused and thus to be a parallel optical.