US 7,248,544 B2 · Optical head and recording and/or reproducing apparatus employing same

Abstract

Disclosed is an optical head in which position adjustment of a photodetector light receiving surface or component parts may be simplified, production costs may be reduced and operational reliability may be improved. The optical head includes a light source 22, radiating light of a preset wavelength, an objective lens 27 for condensing the outgoing light from the light source 22 on an optical disc 2 and for condensing the return light from the optical disc 2, a beam splitter 25 for branching the optical path of the return light reflected by the optical disc 2, and for collimating the branched return light so as to be parallel to the outgoing light from the light source 22, a composite optical component including a splitting prism 30 arranged on a site of incidence of the branched return light for spatially splitting the return light, and a light receiving unit for receiving plural return light beams spatially split by the splitting prism 30 for producing focusing error signals.

Claims30

Dependent claims

An optical head comprising:

a light source for radiating light of a preset wavelength;
a light condensing optical component for condensing the light radiated from said light source on an optical disc and for condensing the return light from said optical disc;
an optical path branching optical component for branching the optical path of the return light reflected from said optical disc and for collimating the branched return light so as to be parallel to the light radiated from said light source;
a composite optical component arranged at a position on which falls the return light branched by said optical path branching optical component, wherein said position is a vicinity of a focal point of the return light, said composite optical component including light splitting means for spatially splitting at least the branched return light;
and
a light receiving unit having a plurality of light receiving areas for receiving a plurality of return light beams obtained on spatial splitting by said light splitting means.

3 more elements

An optical head comprising

a light source for radiating light of a preset wavelength;
a light condensing optical component for condensing the light radiated from said light source on an optical disc and for condensing the return light from said optical disc;
an optical path branching optical component for branching the optical path of the return light reflected from said optical disc and for collimating the branched return light so as to be parallel to the light radiated from said light source;
a composite optical component arranged a position on which falls the return light branched by said optical path branching optical component, wherein said position is a vicinity of a focal point of the return light, said composite optical component including light splitting means for spatially splitting at least the branched return light;
and
a light receiving unit having a plurality of light receiving areas for receiving a plurality of return light beams obtained on spatial splitting by said light splitting means;
said light source being mounted on a heat dissipating member;
said heat dissipating member being provided with an assembly of a substrate or another heat dissipating member and wiring means;
said light receiving unit being arranged on said assembly of the substrate or the other heat dissipating member and wiring means.

6 more elements

A recording and/or reproducing apparatus including an optical head for recording and/or reproducing the information for an optical disc, and disc rotating driving means for rotationally driving said optical disc, wherein said optical head comprises:

a light source for radiating light of a preset wavelength;
a light condensing optical component for condensing the light radiated from said light source on said optical disc and for condensing the return light from said optical disc;
an optical path branching optical component for branching the optical path of the return light reflected from said optical disc and for collimating the branched return light so as to be parallel to the light radiated from said light source;
a composite optical component arranged a position on which falls the return light branched by said optical path branching optical component, wherein said position is a vicinity of a focal point of the return light, said composite optical component including light splitting means for spatially splitting at least the branched return light;
and
a light receiving unit having a plurality of light receiving areas for receiving a plurality of return light beams obtained on spatial splitting by said light splitting means.

3 more elements

Dependencies are inferred from the claim text.

Optical head and recording and/or reproducing apparatus employing same

Life of this patent

Optical head and recording and/or reproducing apparatus employing same

Life of this patent

Abstract

Claims30