Magneto-optical information reproducing apparatus that splits a light beam into at least three light beams advancing in the same direction

A magneto-optical information reproducing apparatus, comprising:

• irradiation means for irradiating a light beam polarized in a predetermined direction onto a recording medium having information magnetically recorded thereon;
• separation means for separating, from the light beam irradiating the recording medium, a light beam from the recording medium;
• splitting means for splitting the light beam separated by said separation means into at least first, second and third light beams, said splitting means comprising (i) a splitting surface having a normal in the same plane as the light beams, (ii) means for emitting the first, second and third light beams in substantially the same direction by said splitting surface, (iii) a non-polarization beam splitter film for splitting the separated light beam into the first light beam, (iv) a polarization beam splitter film for splitting the separated light beam into the second and third light beams, at an angle of 45 degrees with respect to the predetermined direction of polarization of the irradiating light beam and (v) a film for one of reflecting and transmitting the third light beam being provided on a prism surface of said splitting means on which the non-polarization beam splitter film is provided;
• first detection means for detecting the first light beam split by said splitting means to produce one of a focus control signal and a tracking control signal for controlling the light beam irradiating the recording medium;
• and
• second detection means for detecting the second and third light beams split by said prism means to produce a signal for reproducing the information recorded on the recording medium.

A magneto-optical information reproducing apparatus comprising:

• irradiating means for irradiating a light beam polarized in a predetermined direction onto a recording medium having information magnetically recorded thereon;
• splitting means for splitting the light beam from the recording medium into at least first, second and third light beams, and for emitting the first, second and third light beams in substantially the same direction, said splitting means comprising splitting surfaces having a normal in the same plane as the light beams, the splitting surface for splitting the light beam from the recording medium into the first light beam including a non-polarization beam splitter film, the splitting surface for splitting the light beam from the recording medium into the second and third light beams including a polarization beam splitter film, which splits the second and third light beams at an angle of 45 degrees with respect to the predetermined direction of polarization of the irradiating light beam and a splitting surface for one of reflecting and transmitting the third light beam being provided on the splitting surface on which the non-polarization beam splitter is provided;
• first detection means for detecting the first light beam split by said splitting means to obtain one of a focus control signal and a tracking control signal of the light beam guided onto the recording medium;
• and
• second detection means for detecting the second and third light beams split by said splitting means to obtain a reproducing signal of the information recorded onto the recording medium.

A magneto-optical information reproducing apparatus, comprising:

• irradiation means for irradiating a light beam polarized in a predetermined direction onto a recording medium having information magnetically recorded thereon;
• separation means for separating, from the light beam irradiating the recording medium, a light beam from the recording medium;
• prism means for splitting the light beam separated by said separation means into at least first, second and third light beams, and for emitting the first, second and third light beams in substantially the same direction, said prism means comprising (i) a first beam splitter film for splitting the separated light beam into the first light beam, (ii) a second beam splitter film for splitting the separated light beam into the second and third light beams, at an angle of 45 degrees with respect to the predetermined direction of polarization of the irradiating light beam and (iii) a film for one of reflecting and transmitting the third light beam being provided on a prism surface on which said first beam splitter film is provided;
• first detection means for detecting the first light beam split by said prism means to produce one of a focus control signal and a tracking control signal for controlling the light beam irradiating the recording medium;
• and
• second detection means for detecting the second and third light beams split by said prism means to produce a signal for reproducing the information recorded on the recording medium.

A magneto-optical information reproducing apparatus, comprising:

• irradiation means for irradiating a light beam polarized in a predetermined direction onto a recording medium having information magnetically recorded thereon;
• separation means for separating, from the light beam irradiating the recording medium, a light beam from the recording medium;
• splitting means for splitting the light beam separated by said separation means into at least first, second and third light beams, said splitting means comprising (i) a splitting surface having a normal in the same plane as the light beams, (ii) means for emitting the first, second and third light beam, in substantially the same direction by said splitting surface, (iii) a first beam splitter film for splitting the separated light beam into the first light beam, (iv) a second beam splitter film for splitting the separated light beam into the second and third light beams, at an angle of 45 degrees with respect to the predetermined direction of polarization of the irradiating light beam and (v) a film for one of reflecting and transmitting the third light beam being provided on a prism surface of said splitting means on which said first beam splitter film is provided;
• first detection means for detecting the first light beam split by said splitting means to produce one of a focus control signal and a tracking control signal for controlling the light beam irradiating the recording medium;
• and
• second detection means for detecting the second and third light beams split by said prism means to produce a signal for reproducing the information recorded on the recording medium.

A magneto-optical information reproducing apparatus comprising:

• irradiating means for irradiating a light beam polarized in a predetermined direction onto a recording medium having information magnetically recorded thereon;
• splitting means for splitting the light beam from the recording medium into at least first, second and third light beams, and for emitting the first, second and third light beams in substantially the same direction, said splitting means comprising splitting surfaces having a normal in the same plane as the light beams, the splitting surface for splitting the light beam from the recording medium into the first light beam including a first beam splitter film, the splitting surface for splitting the light beam from the recurring medium into the second and third light beams including a second beam splitter film, which splits the second and third light beams at an angle of 45 degrees with respect to the predetermined direction of polarization of the irradiating light beam and a splitting surface for one of reflecting and transmitting the third light beam being provided on the splitting surface on which said first beam splitter is provided;
• first detection means for detecting the first light beam split by said splitting means to obtain one or a focus control signal and a tracking control signal of the light beam guided onto the recording medium;
• and
• second detection means for detecting the second and third light beams split by said splitting means to obtain a reproducing signal of the information recorded onto the recording medium.