TWI426509B - Optical holographic data access system - Google Patents

Description

Optical holographic data reading system

The present invention relates to a data reading system, and more particularly to an optical holographic data reading system for reading data stored at a plurality of recording locations of a recording device.

Conventionally, an optical multilayer recording medium such as a multi-layer optical disc has a memory capacity several times that of an old single-layer recording medium. However, if the data stored on the optical multilayer recording medium is to be read at present, the data stored in each data track of each recording layer is sequentially read by the focused reading beam layer by layer. Reading only the data stored on a single recording layer at a time, that is, the same as the conventional reading method for reading a single-layer recording medium, and not performing the data storage and reading manner for the characteristics of the multi-layer recording medium. improve.

The inventor of the present invention, in the spirit of active invention, considers an "optical holographic data reading system" that can read data stored in a plurality of recording positions of a recording device in a single operation, after several research experiments. Complete this invention to benefit the world.

In view of the above-mentioned conventional data reading system, there is still room for improvement. The object of the present invention is to provide an optical holographic data reading system capable of reading data stored in a plurality of recording positions of a recording device in a single time. A read beam is emitted to the recording positions of the recording device, and a plurality of image corresponding signals generated by the plurality of reflected beams are converted into a plurality of signals.

According to a feature of the present invention, the present invention provides an optical holographic data reading system for cooperating with a recording device for reading data stored in the recording device, the system comprising: a light emitting device for transmitting Reading a plurality of recording positions of the light beam to the recording device to respectively generate a plurality of reflected light beams, wherein the recording positions correspond to a specific position on the surface of the recording device and respectively located at a predetermined depth; and a sensing device receives The reflected beams are respectively imaged at different positions of the sensing device; and a control device is coupled to the light emitting device and the sensing device respectively to control the light emitting device to emit the reading Taking the light beam, the control device converts the plurality of imaging corresponding signals of the reflected light beams to the sensing device into a plurality of signals to read the data recorded on the recording device.

Please refer to FIG. 1. FIG. 1 is a schematic diagram of an optical holographic data reading system according to a preferred embodiment of the present invention. The optical hologram data reading system 2 of the present invention is coupled to a recording device 1 and is used to read data stored in the recording device 1. The optical holographic data reading system 2 includes a control device 21, a writing device 22, a light emitting device 23, a sensing device 24, and a carrying device 25; wherein the control device 21 is associated with the writing device 22, respectively. The light emitting device 23, the sensing device 24, and the carrying device 25 are coupled for control, and the control device 21 converts the plurality of imaging signals of the reflected light beams to the sensing device 24 into a plurality of signals to read and record the Recording device 1; writing device 22 for transmitting a writing beam to recording device 1 to write the data to be written one by one to a plurality of recording positions corresponding to a specific position on the surface of recording device 1, The light emitting device 23 is configured to emit a read beam to the recording positions corresponding to the specific positions to respectively generate a plurality of reflected beams, wherein the read beam is preferably a plane wave or a divergence. a spherical wave; the sensing device 24 receives the reflected light beams, and the reflected light beams are respectively imaged at different positions of the sensing device 24; the carrying device 25 is used to place the recording device 1 to enable the recording device 1 is rotated or moved.

Please refer to FIG. 2. FIG. 2 is a schematic diagram of recording a grating on the recording device 1 according to a preferred embodiment of the present invention. As shown in FIG. 2, the recording device 1 is placed on the carrier device 25 to rotate or move the recording device 1, and is incident on the recording device 1 with two recording beams 31, interfering with the resulting light and dark interference fringes to make the photosensitive molecules in the recording device A change in refractive index is produced. The angle between the two recording beams 31 and the recording device 1 is respectively a predetermined angle α, and the predetermined angle α is determined according to the wavelength, the angle of the reading beam emitted by the light emitting device 23, and the wavelength of the recording light. In the present embodiment, the wavelength of the two recording beams 31 is preferably 532 nm, and the predetermined angle α is preferably 45 degrees, and the wavelength of the reading beam emitted by the light-emitting device 23 is preferably 670 nm.

Please refer to FIG. 3. FIG. 3 is a schematic diagram of writing data to the recording device 1 according to a preferred embodiment of the present invention. As shown in Figure 3, the recording device 1 is placed on the carrier device 25 to rotate or move the recording device 1, the writing device 22 transmits a write beam to the recording device 1 to write data to the recording device 1; Wherein, the energy of the focused beam causes the sensitive molecules to be photosensitive in the dark of the interference fringes, and the refractive index of the recording position is no longer periodically distributed.

Referring to FIG. 4A and FIG. 4B, FIG. 4A is a schematic cross-sectional view of a recording device 1 for writing data according to a preferred embodiment of the present invention, and FIG. 4B is a recording device 1 for writing data according to another preferred embodiment of the present invention. Schematic diagram of the section. The writing operation performed by the writing device 22 on the recording device 1 adjusts the focus position and depth of the written light beam 32 emitted therefrom in accordance with the data to be written to change the refractive index of the focus position. As shown in FIG. 4A, the writing beam 32 can be incident perpendicularly to the recording device 1 to perform a writing operation. As shown in FIG. 4B, the writing beam 32 can be incident on the recording device 1 at an incident angle of a specific angle θ. The data is written on the recording device 1 to form a plurality of data tracks 10. Referring to FIG. 5, FIG. 5 is a schematic diagram of the data track 10 of the recording device 1 according to a preferred embodiment of the present invention. When the optical holography data reading system 2 performs data writing or reading on the recording device 1, the recording device 1 is first placed on the carrier device 25, so that the recording device 1 is rotated by the recording device 1 for recording. The device 1 writes data to form a plurality of data tracks 10 thereon, and the light emitting device 23 emits the read beam 33 along the track direction of the data tracks 10 to be read and stored separately on each data track 10. The depth of the information.

Referring to FIG. 4A and FIG. 5 simultaneously, the writing beam 32 is incident perpendicularly to the recording device 1 for writing; when the information stored on the recording device 1 is to be read, the reading beam 33 is incident on the surface of the recording device 1. At a specific position, the data stored in a plurality of recording positions corresponding to different predetermined depths of a specific position can be read in a single time.

Referring to FIG. 4B and FIG. 5 simultaneously, if the writing beam 32 is incident on the recording device 1 at an incident angle of a specific angle θ, the orbital radius formed by the data track 10 at different predetermined depths is determined by a specific angle θ. With the change of FIG. 4B as an example, the orbital radius of the data track 10 is gradually increased from top to bottom; when the information stored on the recording device 1 is to be read, the reading beam 33 is incident at an incident angle of a specific angle θ. To the data track 10, to read the data stored at each predetermined depth.

Please refer to FIG. 6. FIG. 6 is a schematic diagram of reading data from the recording device 1 according to a preferred embodiment of the present invention. As shown in FIG. 6, the recording device 1 is placed on a carrier device 25, and the light emitting device 23 emits a read beam 33 onto the recording device 1. The sensing device 24 receives the reflected beam 34 generated by the recording device 1, wherein the sensing device Device 24 preferably includes a lens 241 for imaging reflected light beam 34 onto sensing device 24.

Please refer to FIG. 7A. FIG. 7A is a schematic cross-sectional view showing the data read by the recording device 1 according to another preferred embodiment of the present invention. In the present embodiment, as shown in FIG. 7A, the writing beam 32 is written with the incident angle as a specific angle θ, so as to have eight specific positions 111- having different predetermined depths on the data track 10 of the recording apparatus 1. The data is stored on the 118, which can be used to store 1 bit of data, respectively; when it is to be read, the light emitting device 23 emits the reading beam 33 to the recording device 1 at an angle of incidence θ. The read beam 33 is incident on specific locations 111-118 which respectively produce a reflected beam 34 to the sensing device 24 and imaged thereon.

The imaging of the reflected beam 34 on the sensing device 24 changes according to the refractive index of the specific position 111-118. In this embodiment, the specific position 112, 114, 117 is not written with information, which has periodicity. The refractive index of the distribution, thus satisfying the Bragg matching, produces diffracted light, and the specific positions 111, 113, 115, 116, 118 are changed by the write beam 32 to change the refractive index thereon, so that no diffracted light is generated.

Please refer to FIG. 7B at the same time. FIG. 7B is a schematic diagram of imaging on a sensing device according to another preferred embodiment of the present invention. As shown in FIG. 7B, the image formed by the reflected beam 34 on the sensing device 24 is a plurality of imaging points 9. In this embodiment, the control device 21 converts the image points 91-98 corresponding to the specific positions 111-118 into 8-bit signals, that is, 1-byte signals; wherein, the specific data is not written. The positions 112, 114, 117 are generated due to the diffracted light, so the corresponding imaging points 92, 94, 97 are brighter, and the specific positions 111, 113, 115, 116, 118 of the written information are generated due to no diffracted light, so corresponding The image points 91, 93, 95, 96, 98 are darker.

In summary, the optical holographic data reading system of the present invention can read data stored at different predetermined depths in a single plane wave or divergent spherical wave reading light, and thus the optical hologram data of the present invention is used. The reading system reads the information stored on the multi-recording layer recording device, which can effectively improve the reading speed.

The above-mentioned embodiments are merely examples for convenience of description, and the scope of the claims is intended to be limited to the above embodiments.

1. . . Recording device

10. . . Data track

11,111-118. . . Specific location

2. . . Optical holographic data reading system

twenty one. . . Control device

twenty two. . . Write device

twenty three. . . Light emitting device

twenty four. . . Sensing device

241. . . lens

25. . . Carrying device

31. . . Recording beam

32. . . Write beam

33. . . Reading beam

34. . . Reflected beam

9,91-98. . . Imaging point

α. . . Predetermined angle

θ. . . Specific angle

1 is a schematic diagram of an optical holographic data reading system in accordance with a preferred embodiment of the present invention.

2 is a schematic diagram of a recording grating on a recording device in accordance with a preferred embodiment of the present invention.

3 is a schematic diagram of writing data to a recording device in accordance with a preferred embodiment of the present invention.

4A is a schematic cross-sectional view of a data recorded by a recording device in accordance with a preferred embodiment of the present invention.

4B is a schematic cross-sectional view showing the writing of data by a recording device in accordance with another preferred embodiment of the present invention.

Figure 5 is a cross-sectional view showing the data track of the recording apparatus in accordance with a preferred embodiment of the present invention.

6 is a schematic diagram of reading data from a recording device in accordance with a preferred embodiment of the present invention.

Figure 7A is a cross-sectional view showing the reading of data by a recording device in accordance with another preferred embodiment of the present invention.

Figure 7B is a schematic illustration of imaging on a sensing device in accordance with another preferred embodiment of the present invention.

1. . . Recording device

2. . . Optical holographic data reading system

twenty one. . . Control device

twenty two. . . Write device

twenty three. . . Light emitting device

twenty four. . . Sensing device

25. . . Carrying device

Claims (10)

An optical holographic data reading system for cooperating with a recording device for reading data stored in the recording device, the system comprising: a light emitting device for transmitting a reading beam to the recording device Recording positions to respectively generate a plurality of reflected light beams, wherein the recording positions are corresponding to a specific position of the surface of the recording device and respectively located at a predetermined depth; a sensing device receives the reflected light beams, and the same The reflected beams are respectively imaged at different positions of the sensing device; and a control device is coupled to the light emitting device and the sensing device, respectively, to control the light emitting device to emit the read beam, and the control device The reflected light beams are converted into a plurality of signals corresponding to the plurality of imaging devices of the sensing device to read the data recorded on the recording device; wherein the optical holographic data reading system uses the two recording beams Recording means on the recording device, the angle between the two recording beams and the recording device is respectively a predetermined angle, the predetermined angle is dependent on the reading light The wavelength, and angle of the recording light is determined. The optical holographic data reading system of claim 1, wherein the two recording beams have a wavelength of 532 nm, and the wavelength of the reading beam is 670 nm, and the predetermined angle is 45 degrees. The optical holographic data reading system of claim 1, wherein the sensing device further comprises a lens for imaging the reflected beam onto the sensing device. The optical holographic data reading system of claim 1, wherein the reading beam is a plane wave or a divergent spherical wave. The optical holographic data reading system of claim 1, further comprising a writing device coupled to the control device for transmitting a writing beam to the recording device for writing data To the recording device. The optical holographic data reading system of claim 5, wherein the writing beam is incident perpendicularly to the recording device, the reading beam being incident perpendicularly to the recording device. The optical holographic data reading system of claim 5, wherein an incident angle of the writing beam incident on the recording device is a specific angle, and an angle between the reading beam and the recording device It is the specific angle. The optical holographic data reading system of claim 5, wherein the writing operation of the writing device on the recording device adjusts the focus of the writing beam according to the data to be written. Position and depth to change the refractive index of the focus position. The optical holographic data reading system of claim 5, further comprising a carrying device for placing the recording device to rotate or move the recording device to be executed by the writing device The write operation forms a plurality of data tracks on the recording device. The optical holographic data reading system of claim 9, wherein the carrying device further transmits the reading beam to the recording device along a track direction of the data tracks of the recording device; its The read beam is incident on the data tracks to read data thereon.