US 2002/0176349 A1 · Data storage medium utilizing directed light beam and near-field optical sources

Abstract

A data storage unit having a data storage layer with multiple storage areas having a medium disposed thereon that changes between a plurality of states for writing and reading information thereon includes an array of light emitters, such as laser light probes or near-field light sources, spaced in close proximity to the data storage layer for selectively directing light beams to the data storage layer during write and read phases. Data is stored by directing a first light beam to the medium to change to a state representative of data. Data is read by exciting the storage areas with a second directed light beam on the medium. Alternately, the light energy beams in the write or read phases may be generated by a near-field optical system generating evanescent fields. The medium generates electron-hole pairs having substantially different activity in each storage area, depending upon its state. The electron-hole pairs generate activity in a detection region in communication with the storage area that is measured to detect the presence of data. The detection region may comprise a semiconductor diode junction, a photoconductive region or a photo-luminescent region. The presence of data in the storage areas is determined by the number of carriers flowing across the semiconductor junction, the number of carriers flowing in the photoconductive regions between electrodes, or the number of photons generated in the detection portion of the photo-luminescent region.

Claims25

Dependent claims

A data storage unit, comprising:

a data storage layer having a plurality of data storage areas for storing and reading data thereon during read and write phases, respectively;
an array of directed light beam emitters in close proximity to the data storage layer for selectively directing a first light beam to the data storage layer to write data in certain data storage areas during the write phase and for selectively directing a second light beam to the data storage layer to read data in certain data storage areas during a read phase;
a medium disposed on the data storage areas that changes between a plurality of states in response to the first directed light beam during the write phase, and that generates electron-hole pairs in response to the second directed light beam during the read phase, the plurality of states exhibiting substantial differences in the activity of electron-hole carrier pairs generated in response to the second directed light beam;
a detection region in communication with the data storage areas for determining the activity of the electron-hole pairs during the read phase, the activity of electron-hole pairs being relative to the state of each storage areas;
and
a detector associated with the detection region for measuring the activity of the electron-hole carrier pairs to determine the data stored in the data storage areas.

3 more elements

A device for reading data stored in a data storage unit, comprising:

a data storage layer having a plurality of data storage areas including a medium disposed thereon susceptible to changing states in response to the application of energy to the medium;
an array of directed light beam emitters in close proximity to the data storage layer for selectively reading the data stored in the data storage areas by directing light beams to excite the medium in the data storage areas and generate electron-hole pairs, the activity of generated electron-pairs being relative to the state of the medium in each data storage area;
a detection region in communication with the data storage areas for detecting the activity of the electron-hole pairs during the read phase, the amount of activity being variable in response to excitation of the data storage areas by the light beam emitters and the state of the data storage areas;
and
a detector for measuring the amount of electron-hole carrier pair activity in the detection region to determine the data stored in the data storage areas.

2 more elements

A method for writing and reading data in a data storage unit including a data storage layer having a plurality of data storage areas with a medium disposed thereon that is susceptible to changing states in response to light beam energy for storing and reading data thereon during read and write phases, respectively, comprising:

selectively directing a first light beam to the medium to write data in certain data storage areas during the write phase by changing states of the medium using light beam emitters in close proximity to the data storage layer;
selectively directing a second light beam to the medium on the data storage areas to read data in certain data storage areas during the read phase by generating electron-hole pairs, the activity of the electron-hole pairs being relative to the state of the medium;
determining the activity of the electron-hole pairs during the read phase, the activity being in a detection region in communication with the data storage areas, the activity of electron-hole pairs being dependent on the state of each of the data storage areas;
and
measuring the amount of electron-hole carrier pair activity in the detection region to detect the presence of data bits in the storage areas.

2 more elements

Dependencies are inferred from the claim text.

Data storage medium utilizing directed light beam and near-field optical sources

Life of this patent

Data storage medium utilizing directed light beam and near-field optical sources

Life of this patent

Abstract

Claims25