Optical pickup comprising a polygon prism and method of compensating optical axes using the same

摘要

PURPOSE: An optical pick-up unit including a polygonal prism and a method for compensating an optic axis are provided to easily compensate the optic axis and offset a distance tolerance between first and second lights. CONSTITUTION: First and second light sources(23,25) generate first and second lights(23a,25a). An objective lens(43) focuses the first and second lights at a recording medium(55). A photo detector(49) receives the first and second lights for photoelectric transformation. A beam splitter(33) is installed on an optical path between the light sources and the objective lens for converting optical paths of the first and second lights. A polygonal optic axis compensating element(31) is installed on an optical path between the light sources and the beam splitter. The polygonal optic axis includes first and second surfaces(7,9) inclined at a predetermined angle to optic axes to refract the first and second lights, and a third surface in which the optic axes of the first and second lights coincide.