Apparatus and method for detecting holographic data reproduced from a holographic media
View Patent ↗In an apparatus for detecting holographic data reproduced from a holographic medium, the holographic medium has an interference pattern and the holographic data is reproduced when a first portion of a reference beam is diffracted by the interference pattern within the holographic medium. A transmission beam detector detects a light intensity of a transmission beam which is a second portion of the reference beam, wherein the transmission beam is not diffracted to reproduce the holographic data and passes through the holographic medium. Then, a CCD (charge coupled device) controller generates a driving signal in accordance with the detected light intensity. Thereafter, a CCD detects the holographic data in response to the driving signal.
1. An apparatus for detecting holographic data reproduced from a holographic medium, wherein the holographic medium has an interference pattern and the holographic data is reproduced when a first portion of a reference beam is diffracted by the interference pattern within the holographic medium, comprising:
a transmission beam detector for detecting a temporal light intensity of a transmission beam which is a second portion of the reference beam, wherein the transmission beam is not diffracted to reproduce the holographic data and passes through the holographic medium;
a CCD (charge coupled device) controller which generates a driving signal in accordance with the detected light intensity for determining timing in order to detect the holographic data; and
a CCD for detecting the holographic data in response to the driving signal.
2. The apparatus of claim 1 , wherein the CCD controller generates the driving signal when the temporal light intensity of the transmission beam falls below a threshold value.
3. The apparatus of claim 1 , wherein the CCD controller generates the driving signal in a predetermined time after the temporal light intensity of the transmission beam falls below a threshold value.
4. The apparatus of claim 1 , wherein the CCD captures the holographic data on receiving the driving signal.
5. The apparatus of claim 1 , wherein the temporal light intensity of the transmission beam forms a periodical curve over time.
6. An apparatus for reconstructing holographic data, comprising:
a light source for generating a laser beam;
a beam splitter for splitting the laser beam into a reference beam and a signal beam;
a holographic medium for storing an interference pattern generated through an interference of the reference beam with the signal beam; and
a detecting unit for detecting the holographic data reproduced from the holographic medium based on a transmission beam which is not diffracted by the interference pattern to reproduce the holographic data and passes through the holographic medium, wherein the detecting unit includes:
a transmission beam detector for detecting a temporal light intensity of the transmission beam;
a CCD controller which generates a driving signal in accordance with the detected light intensity for determining timing in order to detect the holographic data; and
a CCD for detecting the holographic data in response to the driving signal.
7. The apparatus of claim 6 , wherein the CCD controller generates the driving signal when the temporal light intensity of the transmission beam falls below a threshold value.
8. The apparatus of claim 6 , wherein the CCD controller generates the driving signal in a predetermined time after the temporal light intensity of the transmission beam falls below a threshold value.
9. The apparatus of claim 6 , wherein the CCD captures the holographic data on receiving the driving signal.
10. The apparatus of claim 6 , wherein the temporal light intensity of the transmission beam forms a periodical curve over time.
11. A method for detecting holographic data reproduced from a holographic medium, wherein the holographic medium has an interference pattern and the holographic data is reproduced when a first portion of a reference beam is diffracted by the interference pattern within the holographic medium, comprising the steps of:
detecting a temporal light intensity of a transmission beam which is a second portion of the reference beam, wherein the transmission beam is not diffracted to reproduce the holographic data and passes through the holographic medium;
generating a driving signal in accordance with the detected light intensity for determining timing in order to detect the holographic data; and
detecting the holographic data in response to the driving signal.
12. The method of claim 11 , wherein the driving signal is generated when the temporal light intensity of the transmission beam falls below a threshold value.
13. The method of claim 11 , wherein the driving signal is generated in a predetermined time after the temporal light intensity of the transmission beam falls below a threshold value.
14. The method of claim 11 , wherein the holographic data are captured on the driving signal being received.
15. The method of claim 11 , wherein the temporal light intensity of the transmission beam forms a periodical curve over time.