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US 9,147,426 B2Granted
Optical pickup and optical information storage system including the same
AssigneeToshiba Samsung Storage Technology Korea Corporation
InventorsKi-bok Kim, Ji-sun Ahn, Ju-hee Im, Jin-ho Jeong, Seung-man Han
Life of this patent
Estimating the term…
Abstract
Provided are an optical pickup and an optical information storage system including the same. The optical pickup includes a diffracting element that splits incident light into main light and a plurality of sub light. The diffracting element has at least three regions including first through third regions. A second region is disposed between a first region and a third region and has a phase difference from the first and third regions. The optical pickup detects a tracking error signal by using light diffracted by the diffracting element.
Claims21
An optical pickup, comprising:
- a light source unit;
- a diffracting element configured to split light incident from the light source unit into a main light beam and sub light beams, the diffracting element comprising three regions including a second region disposed between first and third regions and which comprises a periodic structure having a different phase than periodic structures of the first and third regions;
- and
- a photodetector configured to receive the main light and the sub light reflected from an optical information storage medium, and configured to detect a tracking error signal using zeroth-order light diffracted by the diffracting element as main light and using one of first-order light or second-order light diffracted by the diffracting element as sub light based on a type of the optical information storage medium being detected, wherein
- the photodetector is configured to
- detect an eccentric disc response ability indicative of a level of variation in the tracking error signal and based on a spacing between a first main light receiving part and a first sub light receiving part and/or the spacing between a second main light receiving part and a second sub light receiving part, and
- to use the first-order light as sub light in response to a CD being detected, and use the second-order light as sub light in response to a DVD-RW or a DVD-RAM being detected.
4 more elements
An optical pickup, comprising:
- a light source unit configured to emit light of a first wavelength for a digital versatile disc (DVD) and light of a second wavelength for a compact disc (CD);
- a diffracting element configured to split light incident from the light source unit into a main light beam and sub light beams, the diffracting element comprising three regions including a second region disposed between first and third regions and which comprises a periodic structure having a different phase than periodic structures of the first and third regions;
- and
- a photodetector configured to receive the main light and the sub light reflected from optical information storage medium, and configured to detect a tracking error signal using zeroth-order light diffracted by the diffracting element as main light and using one of first-order light and second-order light diffracted by the diffracting element as sub light based on whether the optical information storage medium is a DVD or a CD, wherein
- the photodetector is configured
- to detect an eccentric disc response ability indicative of a level of variation in the tracking error signal and based on a spacing between a first main light receiving part and a first sub light receiving part and/or the spacing between a second main light receiving part and a second sub light receiving part, and
- to use the first-order light as sub light in response to the CD being detected, and use the second-order light as sub light in response to the DVD-RW or the DVD-RAM being detected.
4 more elements
An optical disc drive, comprising:
- an optical pickup device configured to read data from and/or write data to an information storage medium, the optical pickup device comprising:
- a diffracting element with regions, each of the regions having a different phase, and
- a photodetector configured to receive a main light beam and sub-light beams reflected from the information storage medium and passing through the diffracting element with the regions having different phases, and configured to detect a tracking error signal using zeroth-order light as main light and further using one of first-order light and second-order light as sub-light based on a type of the information storage medium, wherein
- the photodetector is
- configured to detect an eccentric disc response ability indicative of a level of variation in the tracking error signal and based on a spacing between a first main light receiving part and a first sub light receiving part and/or the spacing between a second main light receiving part and a second sub light receiving part, and
- configured to use the first-order light as sub light in response to a CD being detected, and use the second-order light as sub light in response to a DVD-RW or a DVD-RAM being detected;
- and
- a control circuit configured to control the optical pickup device to detect the tracking error signal.
5 more elements
Dependencies are inferred from the claim text.