Differential phase detection device and tracking error signal detection apparatus using the same
First Claim
1. A differential phase detection device detecting a differential phase signal from first through fourth signals, the differential phase detection device comprising:
- a slicer slicing and digitizing each of the first through fourth signals with respect to a reference level;
a first synthesizer synthesizing the first digitized signal and the third digitized signal to generate a first synthesis signal;
a second synthesizer synthesizing the second digitized signal and the fourth digitized signal to generate a second synthesis signal;
a phase difference detector comparing a phase of the first synthesis signal with a phase of the second synthesis signal to generate a first phase difference signal and a second phase difference signal; and
a matrix circuit determining a difference between the first and second phase difference signals received from the phase difference detector to output the differential phase signal.
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Abstract
A differential phase detection device receives first through fourth detection signals from a photodetector and detects a differential phase signal therefrom, the differential phase detection device includes a slicer slicing and digitizing each of the detection signals with respect to a reference level. A synthesizer synthesizes the digitized detection signals and generates therefrom synthesis signals. A phase difference detector compares phases of the synthesis signals and outputs a first phase difference signal and a second phase difference signal. A matrix circuit processes the first and second phase difference signals to output the differential phase signal.
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Citations
40 Claims
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1. A differential phase detection device detecting a differential phase signal from first through fourth signals, the differential phase detection device comprising:
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a slicer slicing and digitizing each of the first through fourth signals with respect to a reference level;
a first synthesizer synthesizing the first digitized signal and the third digitized signal to generate a first synthesis signal;
a second synthesizer synthesizing the second digitized signal and the fourth digitized signal to generate a second synthesis signal;
a phase difference detector comparing a phase of the first synthesis signal with a phase of the second synthesis signal to generate a first phase difference signal and a second phase difference signal; and
a matrix circuit determining a difference between the first and second phase difference signals received from the phase difference detector to output the differential phase signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
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21. A differential phase detection device receiving first through fourth detection signals from a photodetector to detect therefrom a differential phase signal, the differential phase detection device comprising:
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a slicer slicing and digitizing each of the detection signals with respect to a reference level;
a synthesizer synthesizing the digitized detection signals and generating therefrom synthesis signals;
a phase difference detector comparing phases of the synthesis signals and outputting a first phase difference signal and a second phase difference signal; and
a matrix circuit processing the first and second phase difference signals to output the differential phase signal. - View Dependent Claims (22, 23, 24, 25, 26, 27, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40)
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28. A tracking error signal detection apparatus, comprising:
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a photodetector comprising first through fourth division plates which are disposed counterclockwise or clockwise along directions corresponding to radial and tangential directions of the recording medium, wherein the first and third division plates are positioned in one diagonal direction and the second and fourth division plates are position in another diagonal direction and the first through fourth division plates receive light reflected from a recording medium to generate first through fourth detection signals, respectively; and
a differential phase detection device detecting a tracking error signal from the first through fourth detection signals output from the photodetector, the differential phase detection device comprising;
a slicer slicing and digitizing each of the first through fourth detection signals with respect to a reference level, a first synthesizer synthesizing the first digitized signal and the third digitized signal to generate a first synthesis signal, a second synthesizer synthesizing the second signal and the fourth signal to generate a second synthesis signal, a phase difference detector comparing a phase of the first synthesis signal with a phase of the second synthesis signal to generate a first phase difference signal and a second phase difference signal, respectively, and a matrix circuit processing the first and second phase difference signals received from the phase difference detector to output a tracking error signal.
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Specification