Optical element, optical head using the optical element, and optical recording and reproducing apparatus using the optical element

An optical element comprising:

• a voltage applying electrode provided with a plurality of segment electrodes;
• an opposing electrode arranged substantially in parallel to the voltage applying electrode and opposing the voltage applying electrode;
• and
• a phase changing layer made of a phase changing material arranged between the voltage applying electrode and the opposing electrode;
• wherein a phase of light entering the phase changing layer is changed by changing a voltage between the voltage applying electrode and the opposing electrode;
• the voltage applying electrode is partitioned by separation portions into the plurality of segment electrodes;
• and
• the width of the separation portions is such that the entire phase changing layer located above the separation portions is influenced by the segment electrodes.

An optical element comprising:

• a voltage applying electrode provided with a plurality of segment electrodes;
• an opposing electrode arranged substantially in parallel to the voltage applying electrode and opposing the voltage applying electrode;
• a phase changing layer made of a phase changing material arranged between the voltage applying electrode and the opposing electrode;
• wherein a phase of light entering the phase changing layer is changed by changing a voltage between the voltage applying electrode and the opposing electrode;
• the voltage applying electrode is partitioned by separation portions into the plurality of segment electrodes;
• and
• the optical element further comprises a light-blocking film blocking light from passing through the separation portions.

An optical head for optically reading information stored on an optical recording medium, the optical head comprising:

• a light source;
• and
• an optical element arranged between the optical recording medium and the light source, the optical element comprising:
• a voltage applying electrode provided with a plurality of segment electrodes;
• an opposing electrode arranged substantially in parallel to the voltage applying electrode and opposing the voltage applying electrode;
• and
• a phase changing layer made of a phase changing material arranged between the voltage applying electrode and the opposing electrode;
• wherein a phase of light entering the phase changing layer is changed by changing a voltage between the voltage applying electrode and the opposing electrode;
• and
• the voltage applying electrode further comprises a voltage control electrode made of a conductive material, which divides a voltage applied from the outside with resistances of the conductive material and applies the divided voltages to the segment electrodes.

An optical head for optically reading information stored on an optical recording medium, the optical head comprising:

• a light source;
• and
• an optical element arranged between the optical recording medium and the light source, the optical element comprising:
• a voltage applying electrode provided with a plurality of segment electrodes;
• an opposing electrode arranged substantially in parallel to the voltage applying electrode and opposing the voltage applying electrode;
• and
• a phase changing layer made of a phase changing material arranged between the voltage applying electrode and the opposing electrode;
• wherein a phase of light entering the phase changing layer is changed by changing a voltage between the voltage applying electrode and the opposing electrode;
• the voltage applying electrode is partitioned by separation portions into the plurality of segment electrodes;
• and
• the width of the separation portions is such that the entire phase changing layer located above the separation portions is influenced by the segment electrodes.

An optical head for optically reading information stored on an optical recording medium, the optical head comprising:

• a light source;
• and
• an optical element arranged between the optical recording medium and the light source, the optical element comprising:
• a voltage applying electrode provided with a plurality of segment electrodes;
• an opposing electrode arranged substantially in parallel to the voltage applying electrode and opposing the voltage applying electrode;
• a phase changing layer made of a phase changing material arranged between the voltage applying electrode and the opposing electrode;
• wherein a phase of light entering the phase changing layer is changed by changing a voltage between the voltage applying electrode and the opposing electrode;
• the voltage applying electrode is partitioned by separation portions into the plurality of segment electrodes;
• and
• the optical element further comprises a light-blocking film blocking light from passing through the separation portions.

An optical reading and recording apparatus for recording or reproducing signals on an optical recording medium, the apparatus comprising:

• an optical head for recording or reproducing signals on the optical recording medium, the optical head comprising a light source, and an optical element arranged between the optical recording medium and the light source, the optical element comprising:
• a voltage applying electrode provided with a plurality of segment electrodes;
• an opposing electrode arranged substantially in parallel to the voltage applying electrode and opposing the voltage applying electrode;
• and
• a phase changing layer made of a phase changing material arranged between the voltage applying electrode and the opposing electrode;
• wherein a phase of light entering the phase changing layer is changed by changing a voltage between the voltage applying electrode and the opposing electrode;
• and
• the voltage applying electrode further comprises a voltage control electrode made of a conductive material, which divides a voltage applied from the outside with resistances of the conductive material and applies the divided voltages to the segment electrodes.

An optical reading and recording apparatus for recording or reproducing signals on an optical recording medium, the apparatus comprising:

• an optical head for recording or reproducing signals on the optical recording medium, the optical head comprising a light source, and an optical element arranged between the optical recording medium and the light source, the optical element comprising:
• a voltage applying electrode provided with a plurality of segment electrodes;
• an opposing electrode arranged substantially in parallel to the voltage applying electrode and opposing the voltage applying electrode;
• and
• a phase changing layer made of a phase changing material arranged between the voltage applying electrode and the opposing electrode;
• wherein a phase of light entering the phase changing layer is changed by changing a voltage between the voltage applying electrode and the opposing electrode;
• the voltage applying electrode is partitioned by separation portions into the plurality of segment electrodes;
• and
• the width of the separation portions is such that the entire phase changing layer located above the separation portions is influenced by the segment electrodes.

An optical reading and recording apparatus for recording or reproducing signals on an optical recording medium, the apparatus comprising:

• an optical head for recording or reproducing signals on the optical recording medium, the optical head comprising a light source, and an optical element arranged between the optical recording medium and the light source, the optical element comprising:
• a voltage applying electrode provided with a plurality of segment electrodes;
• an opposing electrode arranged substantially in parallel to the voltage applying electrode and opposing the voltage applying electrode;
• and
• a phase changing layer made of a phase changing material arranged between the voltage applying electrode and the opposing electrode;
• wherein a phase of light entering the phase changing layer is changed by changing a voltage between the voltage applying electrode and the opposing electrode;
• the voltage applying electrode is partitioned by separation portions into the plurality of segment electrodes;
• and
• the optical element further comprises a light-blocking film blocking light from passing through the separation portions.