Optical pickup apparatus having wedge-shaped beam splitter(s)

An optical pickup apparatus for minimizing astigmatic aberrations, comprising:

• a first light source and a first light detector placed separately;
• a first wedge-shaped beam splitter placed at a light path of divergent or convergent light and having different inclination angles with respect to light beams incident thereto;
• a second light source placed apart from said first light source;
• a second wedge-shaped beam splitter, placed at a light path of divergent or convergent light and at an intersection of light beams emitted by said second light source and light beams passing through said first wedge-shaped beam splitter, said second wedge-shaped beam splitter having different inclination angles with respect to light beams incident thereto;
• a beam focuser to focus light beams passing through said second wedge-shaped beam splitter toward an optical recording medium;
• and
• a hologram pick-up module including said second light source and a second light detector,
• wherein said first light detector receives a light reflected from said first wedge-shaped beam splitter, and said second light detector receives a light reflected from said second wedge-shaped beam splitter.

An optical pickup apparatus comprising:

• a first light source and a first light detector placed separately;
• a first wedge-shaped beam splitter to pass therethrough a light from the first light source and to reflect a first impinging return light onto the first light detector;
• a hologram pickup module including a second light source and a second light detector;
• and
• a second wedge-shaped beam splitter placed at an intersection of a light emitted by the second light source and the light passing through the first wedge-shaped beam splitter,
• wherein the second wedge-shaped beam splitter passes therethrough the light passed through the first wedge-shaped beam splitter, and reflects a second impinging return light onto the second light detector.