JPH04362986A - information recording device - Google Patents

Abstract

PURPOSE:To speed up the recording by moving a recording medium continuously in the travel direction of an ultrasonic wave as fast as interference fringes which move on the surface of the recording medium. CONSTITUTION:An ultrasonic deflector 14 is driven with an amplitude-modulated signal AM passed through a power amplifier 13 to generate carrier diffracted light DF0 and lower-wave diffracted light DF5 which have Doppler shifts nu0 and nu0-nu5 in frequency from a frequency nuB when laser light RB of beam vibration frequency nuB is made incident from a light source 1 for recording. Further, a collimator lens 15 converts the diffracted light beams DF0 and DF5 from the ultrasonic deflector 14 into parallel light beams and makes the diffracted light DF0 incident on a spatial optical modulator 4. An objective 16 converges the signal light SN of the spatial optical modulator 4 and makes it incident on the recording medium, and also converges the diffracted light DF5 passed through the collimator lens 15 and makes it incident as reference light on the incidence area of the recording medium 5 for the signal light SN.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to an apparatus for recording information as a hologram by interference of two laser beams, and more particularly to an information recording apparatus capable of multiplex recording high-quality holograms on a moving medium. It is.

0002

2. Description of the Related Art Rewritable optical disks as information recording devices have begun to become popular primarily as external storage media for computer systems, replacing conventional magnetic disks and the like. As its basic performance, approximately 5×105 b
It has a recording density of IT/mm2, and one 5-inch optical disc has a storage capacity equivalent to 3,300 newspaper pages.

[0003] However, as information communication technology progresses, it is thought that information storage technology capable of higher-density and higher-speed data transfer will be required. In particular, in the field of video communication services, which is proposed as a future service vision,
Ultra high speed (1 Gbit/sec) and high density (1 Gbit/sec) and high density (1
08 bit/mm2) storage system is required. In order to cope with this, research is currently underway in various places to increase density using short wavelength lasers and increase data transfer speeds using multi-beams. However, in terms of recording density, even if recording and reproducing using a short wavelength laser is realized, the limit is considered to be at most 10 times that of current optical discs. Furthermore, since the recording principle is so-called thermal recording, which involves heating and cooling the medium by irradiation with laser light, the recording density is also limited by thermal interference between bits. Regarding transfer speed, due to the numerical limitations of multi-beams,
In principle, it is impossible to significantly improve performance with the conventional bit-high-bit recording and reproducing method.

[0004] As described above, in terms of recording density and data transfer speed, it is not possible to expect a significant performance improvement in current storage systems using optical disks. In order to overcome these limitations, it is necessary to establish a new storage method that enables higher density through multiple recording and faster processing through multiple bit batch processing.

[0005] The basic device configuration for batch recording and reproducing of two-dimensional digital information using the hologram recording method, which has been studied so far, is described in the document ``APPLIED'', for example.
OPTICS/Vol. 3, No. 4/April
1974, pages 808 to 810.
hicRead-Write Memory Us
ing 3-D Storage"Author nameL.d'
Auria, J. P. Huignard, C. Slez
ak, and E. It has already been proposed by Spitz. According to this document, laser light is diffracted by an acousto-optic element capable of two-dimensional light deflection, and the first-order diffracted light is split into two directions by a beam splitter. One is collimated by a collimating lens and then addressed to a specific lens in the lens array. In the page composer, a two-dimensional bit pattern that constitutes one page of information is formed, and a beam spread by an addressed specific lens on the lens array becomes signal light by irradiating the page composer. The signal light is focused onto one point on the hologram recording medium by a Fourier transform lens. The other beam split by the beam splitter is superimposed as a reference beam on the convergence position of the signal beam on the recording medium by an electro-optical element and a holographic diffraction grating. In this way, the two-dimensional digital information formed by the page composer is recorded as a minute hologram.

[0006] In order to form holograms at different positions on the recording medium, the first-order diffracted light is deflected in a different direction from the above using an acousto-optic element. Therefore, minute holograms are arranged in a two-dimensional matrix on a stationary recording medium. Furthermore, by deflecting only the reference light using the electro-optical element, it is possible to multiplex record holograms having different information at the recorded hologram positions.

[0007] Reproduction is performed all at once by accessing the minute holograms using the reference light used during recording, and the two-dimensional bit pattern formed by the page composer is detected by the detector array.

However, in this method, a complicated optical system is required to access an arbitrary hologram and convert the reference beam angle during angle multiplex recording, so it is difficult to achieve high-speed and high-precision beam processing. Difficult to access. Furthermore, since there is no function to exchange the recording medium, the storage capacity is limited by the number of resolution points of the acousto-optic deflector or the number of array lenses.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and its object is to provide an information recording device that can multiplex record two-dimensional digital information accurately and at high speed on a moving medium. It is about providing.

0010

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a recording light source that emits a laser beam, a carrier wave signal generating means that generates a carrier wave signal of a predetermined frequency, and a frequency of the carrier wave signal. input signal generating means for generating input signals for amplitude modulation of different frequencies; and amplitude modulating means connected to the carrier wave signal generating means and the input signal generating means and amplitude modulating the carrier wave signal with the input signal. , an ultrasonic light deflecting means connected to the amplitude modulation means, receiving the laser light from the recording light source, and diffracting the laser light in two directions by an amplitude modulation signal from the amplitude modulation means; a diffracted light modulating means for imparting predetermined information to the diffracted light of the laser beam diffracted in one direction by the deflecting means, modulating the diffracted light to produce a signal light; A movable recording medium means for irradiating a reference light, which is a diffracted light of a laser beam diffracted in a direction different from that of the signal light, onto the same incident area by a sonic light deflection means, and recording interference between the two. Provides an information recording device.

[0011]

[Operation] A carrier wave signal of a frequency ν0, for example, generated by the carrier wave signal generating means and an input signal of a frequency νS different from that of the carrier wave signal generated by the input signal generating means are input to the amplitude modulating means.

The amplitude modulation means amplitude modulates the carrier signal with the input signal. As a result, νO and νO −νS
(lower side wave), νO + νS (upper side wave) frequency components are generated. As a result, the amplitude modulation means outputs an amplitude modulation signal having these as frequency components, and inputs it to the ultrasonic optical deflector.

In parallel with this, a light beam having a predetermined beam vibration frequency νB from a recording light source is incident on the ultrasonic light deflector. As a result, in the ultrasonic optical deflector,
From the frequency νB, the frequencies are νO and νO −ν, respectively.
Diffracted light that has undergone a Doppler shift by S is generated.

One of these diffracted lights is input to a diffracted light modulation means, where it is subjected to a predetermined modulation effect, predetermined information is added thereto, and is incident on a predetermined position of the recording medium as a signal light. be done.

Further, the other diffracted light is incident on the signal light incident area of the recording medium as a reference light. As a result, the signal light and the reference light interfere, and information is recorded.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the basic configuration of an information recording apparatus according to the present invention. Reference numeral 1 denotes a recording light source, which is composed of, for example, a laser having a beam vibration frequency νB. 4 is a spatial light modulator which modulates one of the diffracted lights DFO (described later) to give two-dimensional information and outputs it as signal light SN. Reference numeral 5 denotes a recording medium, on which information is recorded as a hologram by the incidence of the signal light SN and the reference light RF. A photodetector array 6 detects reproduction light RD during reproduction of recorded information.

10 is a carrier signal generator with a frequency νO
A carrier wave signal CF is generated.

Reference numeral 11 denotes an input signal generator that generates an amplitude modulation input signal IS having a frequency νS.

Reference numeral 12 denotes an amplitude modulator, which amplitude modulates the carrier signal CF with the input signal IS, and generates νO (carrier wave), νO −νS (lower side wave), νO as a result of this amplitude modulation.
Among the frequency components of +νS (upper side wave), the upper side wave is cut by a low-pass filter (not shown), and νO and νO
An amplitude modulated signal AM having a frequency component of -νS is output.

A power amplifier 13 amplifies the amplitude modulated signal AM from the amplitude modulator 12 with a predetermined gain.

14 is an ultrasonic optical deflector, and a power amplifier 13
When the laser beam RB is driven by the amplitude modulation signal AM via the recording light source 1 and has a beam vibration frequency νB from the recording light source 1, the frequencies νO and νO − are caused by νB, respectively.
Carrier wave diffracted light DF subjected to Doppler shift by νS
O, generates lower side wave diffracted light DFS.

Reference numeral 15 denotes a collimator lens having a focal length f1, and the diffracted light DFO, DFS by the ultrasonic optical deflector 14 is
is converted into parallel light, and the diffracted light DFO is sent to the spatial light modulator 4.
incident on .

Reference numeral 16 denotes an objective lens with a focal length f2, which focuses the signal light SN from the spatial light modulator 4 and makes it incident on the recording medium 5, and also focuses the diffracted light DFS through the collimator lens 15 for reference. The signal light SN is made incident on the recording medium 5 as light into the incident area of the signal light SN.

Next, the information recording operation and the ability to record holograms on a moving recording medium with the above configuration will be explained step by step.

A carrier wave signal CF of a frequency νO generated by a carrier wave signal generator 10 and an input signal IS of a frequency νS generated by an input signal generator 11 are input to an amplitude modulator 12.

In the amplitude modulator 12, the carrier signal CF is amplitude-modulated by the input signal IS. As a result, νO and ν
Frequency components of O − νS (lower side wave) and νO +νS (upper side wave) are generated. Among the generated frequency components, the upper side wave is removed by a low-pass filter (not shown), and νO
and νO −νS as frequency components
M is output. This amplitude modulated signal AM is amplified by a power amplifier 13 and then input to an ultrasonic optical deflector 14 .

In parallel with this, a light beam RB from the recording light source 1 whose beam vibration frequency is νB is incident on the ultrasonic light deflector 14. Along with this, carrier wave diffraction light DFO and lower side wave diffraction light DFS are generated whose frequencies are Doppler shifted by νO and νO - νS from frequency νB, respectively.

Here, the amplitude distribution of the ultrasonic carrier wave diffracted light DFO with the frequency νB −νO is ψO (x),
Frequency νB - (νO - νS) If the amplitude distribution of the lower side wave diffracted light DFS of the ultrasonic wave is ψS (x), then the following (
It is expressed by equations 1) and (2).

ψO (x)=A(x)exp (−2πiν
O / Va ・x)・
exp {−2πi(νB −νO )t}
…(1) ψS (x)=
a(x)exp {−2πi(νO −νS )/Va
・x}・
exp {−2πi(νB −νO +νS )t}
...(2) However, Va is the sound velocity of the ultrasonic wave, and x is a coordinate axis set on the ultrasonic light deflector 14, with the direction of propagation of the ultrasonic wave being positive.

These carrier wave diffracted light DFO and lower side wave diffracted light DFS are converted into parallel lights after passing through the collimator lens 15, and one of the diffracted lights DFO passes through the spatial light modulator 4 and is emitted as signal light SN. Ru.

The signal light SN is condensed by the objective lens 16 and is incident on a predetermined position on the recording medium 5. Further, the lower side wave diffracted light DFS converted into parallel light by the collimator lens 15 is subjected to a condensing action by the objective lens 16 and is incident on the incident area of the signal light SN of the recording medium 5. As a result, both the signal light SN and the reference light RF interfere with each other on the recording medium 5 surface.

For the sake of simplicity, the information pattern of the spatial light modulator 4 will now be described in the case where, for example, all the information patterns are "1", that is, the entire amount of signal light SN passes through the spatial light modulator 4. After the signal light SN passes through the objective lens 16, the reference light RF (ψO
), the signal light SN (ψS ) is expressed by the following equations (3) and (4).

ψO (-y/M) = A(-y/M)exp {2πiνO
/Va ・(y/M)}・
exp {−2πi(νB −νO )t}
…(3) ψS (−
y/M) = a(-y/M)exp {2πi(νO
-νS )/Va ・(y/M)}・
exp {−2πi(νB −
νO +νS )t} (4) where M is the imaging magnification and is given by M=f2/f1.

Furthermore, the coordinate axis fixed on the 5th surface of the recording medium is y
', the coordinate axis y is transformed as shown in the following equation (5).

y=y′−Vd·t

...(5) However, Vd is the moving speed of the recording medium 5.

[0036] Therefore, ψO and ψS are as follows (6),
It can be expressed as shown in equation (7).

ψO {−(y′−Vd·t)M}=A{−
(y'-Vd ・t)/M} exp
(2πiνO /Va ・(y'-Vd ・t)/M}
・ exp {−2πi(νB −νO
)t}
...(6) ψS {-(y'-Vd ・t)/
M}=a{-(y'-Vd ・t)/M}
exp {2πi(νO −νS )/Va ・(
y'-Vd ・t)/M}・exp
{−2πi(νB −νO +νS )t}
(7) Furthermore, the light intensity distribution after interference between the reference light RF and the signal light SN is expressed by the following equation (8).

[0038]

[Math 1]

Now, assuming a Gaussian distribution as the envelope function of both amplitude distributions, A{-(y'-Vd ・t)/M}=AO e
xp {-(y'-Vd ・t)/w}2...(9
) a{-(y'-Vd ・t)/M}=aS
exp {-(y'-Vd ・t)/w}2...(
10). However, w is the beam radius.

Therefore, in the above equation (8), (9) and (10)
Substitute the formula and Va ・f2 /f1 =Vd

...If the condition (11) is set, the above equation (8) can be expressed as the following equations (12) and (13).

[0041]

[Math 2]

[0042]λS=VS/Vd

...(13) These equations (12) and (13) are (
This shows that if the condition 11) is satisfied, the interference fringes will form a fixed pattern on the five surfaces of the recording medium regardless of the time term.

That is, as explained above, according to this embodiment, two diffracted lights DFO and DFS having different frequencies due to ultrasonic light diffraction are used, and the movement of the interference fringes of both diffracted lights is canceled. Because the medium is moving, holograms can be recorded on a continuously moving medium.

Note that the above results indicate that the spatial light modulator 4
These are the results assuming that all the patterns are "1", that is, the entire amount of incident light is transmitted. When the spatial light modulator 4 has a random two-dimensional digital information pattern, this information pattern is Fourier-transformed by the objective lens 16, and the signal light having that portion interferes with the reference light, thereby recording a hologram. In this case as well, Va ・f2 shown in the above equation (11)
If the condition /f1=Vd is satisfied, the hologram will be fixed and recorded on the 5th surface of the recording medium.

FIG. 2 shows reference beams RF1, RF2, RF
An example is shown in which high-speed, multiplex recording is possible by making the incident angles on the three recording media 5 different.

Specifically, the incident angle of the reference light RF is changed by changing the input signal IS for amplitude modulation by the input signal generator 11.
This can be changed by switching the frequency.

[0047] In such a recording system, multiple recording becomes possible by applying a recording medium that can form a volume hologram that allows multiple recording due to the difference in the incident angle of the reference beam RF.

It should be noted that the blocks shown in FIG. 2 are given the same reference numbers as the blocks shown in FIG. 1, and the explanation of their configurations will be omitted.

[0049] As a medium that can be applied to such a volume hologram, for example, Bi12SiO20 (BSO) is used.
, Srx Ba1-x Nb2 O6 (SBN), L
A dielectric crystal such as iNbO3 or a semiconductor crystal such as GaP or GaAs can be used.

Furthermore, since switching of the frequency of the amplitude modulation input signal IS can be electrically controlled, it becomes easy to speed up multiplex recording.

Next, another embodiment of the information recording apparatus of the present invention will be described with reference to FIGS. 3 and 4. Furthermore, Figure 3
The same parts as in FIGS. 1 and 2 in the block are given the same reference numerals, and the explanation of the structure will be omitted.

The embodiment shown in FIG. 3 has different frequencies νO1
, νO2, νO3, the plurality of carrier wave diffracted lights DFO1, DFO2, DFO3 generated from the ultrasonic light deflector 14 are respectively driven by the carrier wave signals having the carrier wave signals DFO1, νO2, νO3.
A plurality of signal lights are obtained through the channels a, 4b, and 4c, and these signal lights are incident on the surface of the recording medium 5.

[0053] Each of these signal lights and the corresponding reference lights RFO1, RFO2, and RFO3 are incident on a predetermined position on a moving recording medium, and interference fringes are sequentially recorded, allowing high-density recording. becomes. This example will be explained below.

4a, 4b, and 4c are spatial light modulators, and carrier wave diffraction lights DFO1, RFO2, and RFO, which will be described later, respectively.
3 to give different two-dimensional information, and output as signal lights SN1, SN2, and SN3. Also,
The time required to form an information pattern in each of the spatial light modulators 4a, 4b, and 4c is Ts, and the information pattern switching time of the information recording apparatus is set to Ta as shown in FIG. 4. Here, it is assumed that Ta<Ts. That is, the spatial light modulator 4
Since formation of each bit pattern is completed approximately after a time Ts after being driven, the spatial light modulators 4a, 4b, and 4c are sequentially started to be driven with a time difference Ta.

Reference numeral 5 denotes a recording medium, which is disposed so as to be movable in the vertical direction in the figure by a moving mechanism, and which receives signal beams SN1 and SN2.
, SN3 and the reference light RF corresponding to each signal light.
Information is recorded as a hologram by the incidence of O1, RFO2, and RFO3. A photodetector array 6 detects reproduction light RD during reproduction of recorded information.

10 is a carrier wave signal generator which, as shown in FIG. 4, generates frequencies νO1, νO2,
Carrier wave signals CF1, CF2, and CF3 of νO3 are sequentially generated.

Reference numeral 11 denotes an input signal generator that generates an input signal IS for amplitude modulation having a frequency νS.

12 is an amplitude modulator for each carrier signal CF1.
, CF2, CF3 are amplitude-modulated by the input signal IS, and as a result of this amplitude modulation, νO1(O2, O3) and νO1(O2, O3) -νS (lower side wave), νO1(
Among the frequency components of +νS (upper side wave), for example, the upper side wave is removed by a low-pass filter (not shown), and νO1(O2, O3) and νO1(O2, O3) are obtained.
An amplitude modulated signal AM having a frequency component of -νS is emitted.

14 is an ultrasonic optical deflector, and an amplitude modulator 12
The recording light source 1 is driven by an amplitude modulated signal AM by
When a light beam RB with a beam vibration frequency νB is incident, the frequency becomes νO1 (O2, O3
), νO1 (O2, O3) - νS, and the diffracted lights DFO1(O2, O3) and DFS1(S2, S3) are respectively emitted with different diffraction angles.

Reference numeral 15 denotes a collimator lens, and the diffracted light DFO1 (O2, O3), DFS by the ultrasonic optical deflector 14 is
1 (S2, S3) into parallel light and diffracted light DFO1
is incident on the spatial light modulator 4a, the diffracted light DFO2 is incident on the spatial light modulator 4b, and the diffracted light DFO3 is incident on the spatial light modulator 4c.

16 is an objective lens, and each spatial light modulator 4a
, 4b, 4c signal lights SN1, SN2, SN3
is focused and incident on the recording medium 5, and the diffracted light DFS1 (S2, S3) passes through the collimator lens 15.
are focused as reference beams RFO1, RFO2, and RFO3 to signal beams SN1, SN2, and S of the recording medium 5, respectively.
It is made incident on the corresponding incident area of N3.

FIG. 4 shows each spatial light modulator 4a during information recording.
, 4b, 4c, that is, the information pattern formation time, and the switching time of the amplitude modulation signal, that is, the frequency switching time of the carrier wave signal generator 10.

In FIG. 4, Ts is the information pattern formation time, Ta is the supply time of the selected amplitude modulation signal, and t1
, t2 , t3 , ... are each diffracted light DFO1, DFO2
, DFO3 to the spatial light modulators 4a, 4b, and 4c, respectively.

In this embodiment, as shown in FIG. 4, the spatial light modulators 4a, 4b, and 4c are sequentially driven, and at time t1 when the information pattern formation of the spatial light modulator 4a is completed, the amplitude modulator 12 is driven. The diffracted light DFO1 corresponding to the carrier wave obtained by amplitude modulating the carrier frequency νO1 with the modulation frequency νS is incident on the spatial light modulator 4a. At time t2 when the formation of the information pattern of the spatial light modulator 4b is completed, the diffracted light D corresponding to the carrier wave whose carrier frequency νO2 is amplitude-modulated by the modulation frequency νS is generated.
The FS2 is input to the spatial light modulator 4b. Spatial light modulator 4
At time t3 when the formation of the information pattern c is completed, the diffracted light DFO3 corresponding to the carrier wave obtained by amplitude modulating the carrier frequency νO3 with the modulation frequency νS is incident on the spatial light modulator 4c,
By repeating similar operations, hologram recording can be performed on a recording medium that moves at a time interval Ta shorter than the information pattern formation time Ts.

Next, the information recording operation with the above configuration will be explained.

[0066] The spatial light modulators 4a, 4b, 4c are sequentially started to be driven with a time difference Ta. Spatial light modulator 4a
, 4b and 4c, the formation of the information pattern is completed after the time Ts has elapsed since the driving was started.

Further, the carrier wave signal CF1 of the frequency νO1 (O2, O3) generated by the carrier wave signal generator 10
, CF2, CF3 and the input signal IS of frequency νS generated by the input signal generator 11 is input to the amplitude modulator 1.
2 is input.

In the amplitude modulator 12, the carrier signal CF1 is first amplitude-modulated by the input signal IS. the result,
νO1 and νO1−νS (lower side wave), νO1+νS
(upper side wave) frequency component is generated. Among the generated frequency components, an upper side wave is removed by a low-pass filter (not shown), and an amplitude modulated signal AM having frequency components of νO1 and νO1-νS is output, and then input to the ultrasonic optical deflector 14.

In parallel with this, the light beam RB from the recording light source 1 whose beam vibration frequency is νB is incident on the ultrasonic light deflector 14. Diffracted lights DFO1 and DFS1 are generated whose frequencies are Doppler shifted by νO1 and νO1-νS from the frequency νB, respectively.

These diffracted lights DFO1 and DFS1 are converted into parallel lights after passing through the collimator lens 15, and the diffracted lights DFO1 and DFS1 are converted into parallel lights.
FO1 is incident on the spatial light modulator 4a at time t1 after a time Ts has elapsed since the driving of the spatial light modulator 4a was started. The diffracted light DFO1 is transmitted to the spatial light modulator 4a by a predetermined 2
Dimensional information is given to it and it is emitted as signal light SN1.

The signal light SN1 is focused by the objective lens 16 and is incident on a predetermined position on the recording medium 5. Further, the diffracted light DFS1 converted into parallel light by the collimator lens 15 is subjected to a condensing action by the objective lens 16, and is converted into a reference light RFO1 by the signal light SN1 of the recording medium 5.
is incident on the incident area. As a result, signal light SN1
and reference light RFO1 interfere on the recording medium 5 surface,
Interference fringes from both are recorded.

Next, after a period of time Ta has elapsed from the drive start time of the spatial light modulator 4a, the drive of the spatial light modulator 4b is started,
At time t2 after a further period of time Ts has elapsed, the generation frequency of the carrier signal generator 10 is switched from νO1 to νO2.

Accordingly, in the amplitude modulator 12, the carrier wave signal CF2 having the frequency νO2 is amplitude-modulated by the input signal IS having the frequency νS. As a result, an amplitude modulated signal AM having frequency components of νO2 and νO2-νS is output from the amplitude modulator 12 according to the same principle as described above, and is then input to the ultrasonic optical deflector 14.

As a result, in the ultrasonic light deflector 14, the frequencies νO2 and νO2-ν are determined from the beam vibration frequency νB of the incident light beam RB from the recording light source 1, respectively.
Diffracted light DFO2,D which has undergone a Doppler shift by S
FS2 is generated. The diffraction angle of this diffracted light DFO2 is
This is different from the diffraction angle of the diffracted light DFO1.

[0075] The diffracted light DFO2 passes through the collimator lens 15.
After passing through, the light is converted into parallel light and is input to the spatial light modulator 4b. The diffracted light DFO2 is transmitted to the spatial light modulator 4b by a predetermined 2
Dimensional information is given to it and it is emitted as signal light SN2.

At this time, the reference light RFO2 and the signal light SN2 based on the lower side wave diffracted light DFS2 are incident on a predetermined position of the recording medium 5 under the condensing action of the objective lens 16.
Interference fringes from both are recorded.

Furthermore, after a time Ta has elapsed from the driving start time of the spatial light modulator 4b, the driving of the spatial light modulator 4c is started, and at time t3, after a further time Ts has elapsed, the generation of the carrier wave signal generator 10 is started. The frequency is switched from νO2 to νO3.

Accordingly, in the amplitude modulator 12, the carrier wave signal CF3 having the frequency νO3 is amplitude-modulated by the input signal IS having the frequency νS. As a result, an amplitude modulated signal AM having frequency components of νO3 and νO3-νS is output from the amplitude modulator 12 according to the same principle as described above, and is then input to the ultrasonic optical deflector 14.

As a result, in the ultrasonic light deflector 14, the frequencies νO3 and νO3-ν are determined from the beam vibration frequency νB of the incident light beam RB from the recording light source 1.
Diffracted light DFO3,D which has undergone a Doppler shift by S
FS3 is generated. The diffraction angle of this diffracted light DFO3 is
This is different from the diffraction angles of the diffracted lights DFO1 and DFO2 described above.

[0080] The diffracted light DFO3 is transmitted through the collimator lens 15.
After passing through, the light is converted into parallel light and input to the spatial light modulator 4c. The diffracted light DFO3 is transmitted to the spatial light modulator 4c by a predetermined 2
Dimensional information is given to it and it is emitted as signal light SN3.

At this time, the reference light RFO3 and the signal light SN3 based on the lower side wave diffracted light DFS3 are incident on a predetermined position of the recording medium 5 under the condensing action of the objective lens 16.
Interference fringes from both are recorded.

The above operations are repeated, and two-dimensional information is holographically recorded on the recording medium 5.

Note that in such a recording system, if a volume hologram capable of multiple recording is applied, multiple recording becomes possible.

Examples of media capable of recording such a volume hologram include Bi12SiO20 (BSO) and S
rx Ba1-x Nb2 O6 (SBN), LiN
A dielectric crystal such as bO3 or a semiconductor crystal such as GaP or GaAs can be used.

As explained above, according to this embodiment,
Carrier wave signals CF1 and CF2 that generate traveling ultrasound waves
, CF3, the diffraction angle of the diffracted light is changed and the spatial light modulators 4a, 4b, 4c are selected.
, 4b, and 4c, and these are used as signal beams SN1, SN2, and SN3, so that two-dimensional digital information can be holographically recorded on the moving recording medium 5 at high speed. .

In this embodiment, the modulation frequency for changing the diffraction angle of the diffracted light to be used as the signal light is changed by switching the frequencies of the carrier signals CF1, CF2, CF3. carrier wave signals CF1, CF2, CF3
Instead of switching the frequency of the amplitude modulation input signal νS
The same effect as above can be obtained even by switching the frequency of .

That is, by using the diffracted light corresponding to the amplitude modulation input signal IS as the signal light and the diffracted light corresponding to the carrier wave signal as the reference light, by rapidly switching the frequency of the amplitude modulation input signal IS. , the diffraction angle of the signal light can be changed.

Furthermore, in this embodiment, one of the upper and lower side waves (in this embodiment, the upper side wave) generated in the amplitude modulator 12 is removed by a filter (not shown).
However, the present invention is not limited to this, and the frequency νO of the carrier wave signal CF is shifted from the center frequency of the ultrasonic optical deflector 14 without being removed by the amplitude modulator 12, and the frequency of one of the upper and lower side waves is deflected by the ultrasonic optical beam. Of course, the ultrasonic light deflector 14 itself may be configured to remove the light from within the deflection bandwidth of the ultrasonic light deflector 14.

Furthermore, it goes without saying that the number of switching frequencies and the number of spatial light modulators corresponding thereto are not limited to this embodiment.

Next, another embodiment of the information recording apparatus of the present invention will be described with reference to FIG.

In this embodiment, a plurality of laser beams with different wavelengths are incident on an ultrasonic optical deflector simultaneously or sequentially, and diffracted beams in two directions according to the wavelengths of each laser beam are obtained, thereby recording a recording medium. The incident angles of the incident reference beam and signal beam are changed, thereby causing the reference beam and signal beam to interfere on the surface of the moving recording medium, obtaining interference fringes, and performing high-speed multiplex recording.

That is, 1a and 1b are laser light sources having different wavelengths λ1 and λ2, respectively, and are composed of, for example, an argon laser, a Nd:YAG laser, or the like. 14
is an ultrasonic optical deflector which, when driven by an amplitude modulation signal AM from an amplitude modulator 12 (to be described later), generates an ultrasonic wave corresponding to the amplitude modulation signal AM. At this time, the wavelength λ is emitted from the laser light source 1a at an incident angle of Black angle θ1 to this ultrasonic wavefront.
When a laser beam RB1 of 1 is made incident, two diffracted beams Ra and Sa corresponding to frequency components ν1 and ν0 −ν1 are emitted with specific diffraction angles due to black diffraction. Furthermore, when the laser beam RB2 with the wavelength λ2 is incident from the laser light source 1b at the Black angle θ2, two diffracted beams Rb and Sb are similarly generated at different diffraction angles than in the case of the wavelength λ1.

12 is an amplitude modulator that amplitude modulates the carrier signal CF with the amplitude modulation input signal IS, and generates ν0, ν0 - ν1 (lower side wave), ν as a result of this amplitude modulation.
Among the frequency components of 0 + ν1 (upper side wave), for example, the upper side wave is removed by a low-pass filter (not shown), and ν0
and outputs an amplitude modulated signal AM having a frequency component of ν0 - ν1. 11 is an input signal generator, ν0
An amplitude modulation input signal IS having a frequency ν1 different from that of the input signal IS is generated. 10 is a carrier wave signal generator which generates a carrier wave signal CF having a frequency ν0.

Reference numeral 15 denotes a collimator lens that converts the diffracted light by the ultrasonic light deflector 14 into parallel light, and sends the two carrier wave diffracted lights Sa and Sb from the ultrasonic light deflector 14 to the spatial light modulators 4a and 4b, respectively. Inject it into the These spatial light modulators 4a and 4b modulate the two carrier-wave diffracted lights Sa and Sb to give different two-dimensional information, respectively, and output them as signal lights SN.

16 is an objective lens, and each spatial light modulator 4a
, 4b are condensed and made incident on the recording medium 5 moving in a predetermined direction, and the lower side wave diffracted beams Ra and Rb are condensed through the collimator lens 15, and the lower side wave diffracted beams Ra and Rb are condensed to make the recording medium 5 move in a predetermined direction. 5 into the signal light incident area. Note that the recording medium 5 is arranged so as to be movable in the vertical direction of the figure indicated by the arrow by a moving mechanism (not shown). A photodetector array 6 detects reproduction light RD during reproduction of recorded information.

The information recording operation of this embodiment having the above-described configuration will be explained below.

A carrier wave signal CF having a frequency ν 0 generated by the carrier wave signal generator 10 and an input signal IS having a frequency ν 1 generated by the input signal generator 11 are input to the amplitude modulator 12 . In the amplitude modulator 12, the carrier signal CF is amplitude-modulated with the input signal IS. As a result, ν
0 and ν0 −ν1 (lower side wave), ν0 +ν1
(upper side wave) frequency component is generated. Among the generated frequency components, the upper side wave is removed by a low-pass filter (not shown), and an amplitude modulated signal AM having frequency components of ν0 and ν0 - ν1 is output, which is transmitted to the ultrasonic optical deflector 1.
4 is input. As a result, an ultrasonic wave corresponding to this amplitude modulation signal AM is generated within the ultrasonic optical deflector 14. Let the wavelength of the ultrasonic wave at this time be Λ.

In parallel with this, the laser beam RB1 of wavelength λ1 is applied to the ultrasonic light deflector 14 from the laser light source 1a, and the black diffraction condition 2 is applied to the ultrasonic wavefront.
Λsin θ1 = λ1

...When incident at an incident angle θ1 that satisfies (14), diffracted light Sa corresponding to the carrier signal CF and diffracted light Ra corresponding to the lower side wave signal are emitted from the ultrasonic optical deflector 14 at different diffraction angles.
is emitted.

These two diffracted lights Sa and Ra are converted into parallel lights after passing through the collimator lens 15, and the diffracted lights Sa and Ra are converted into parallel lights.
is input to the spatial light modulator 4a, where it is given two-dimensional information and output as signal light SNa. Signal light SNa
is incident on a predetermined position of the moving recording medium 5 under the condensing action of the objective lens 16 . Furthermore, the diffracted light Ra converted into parallel light by the collimator lens 15 is condensed by the objective lens 16, and is converted into a reference light RFa by combining the frequency ν1 of the input signal IS and the incident laser light RB1.
The signal light SNa is incident on the incident area of the recording medium 5 at an incident angle Θ1 determined by the wavelength λ1 of the signal light SNa. As a result, both the signal light SNa and the reference light RFa interfere on the surface of the moving recording medium 5, and interference fringes due to both are recorded.

At this time, at the same time as the laser beam RB1 is emitted, the laser beam RB2 with the wavelength λ2 is emitted from the laser light source 1b.
For the ultrasonic wavefront, Black diffraction conditions 2Λ sin θ2 = λ2

...When the incident angle θ2 satisfies (15), the ultrasonic beam deflector 14 outputs the diffracted beam Sb corresponding to the carrier wave signal CF and the lower side wave signal at a diffraction angle different from that of the laser beam RB1. Diffracted light Rb is emitted.

The diffracted light Sb is converted into parallel light by the collimator lens 15, enters the spatial light modulator 4b, is given two-dimensional information different from that of the spatial light modulator 4a, and is emitted as signal light SNb. The signal light SNb is incident on the same area on the recording medium 5 that moves under the condensing action of the objective lens 16 as the incident area of the signal light SNa and the reference light RFa. After passing through the collimator lens 15, the diffracted light Rb is converted into parallel light, and is then condensed by the objective lens 16 to become the reference light RFb, whose incidence is determined by the frequency ν1 of the input signal IS and the wavelength λ2 of the incident laser light RB2. The signal light S on the recording medium 5 with an angle Θ2
The Nb is incident on the incident region. As a result, the signal light SN
Both the reference beam RFb and the reference beam RFb interfere with each other on the surface of the moving recording medium 5, and interference fringes due to the two are recorded. At this time, since the laser beams emitted from different laser light sources have no interference, the signal beam SNa and the reference beam RFb and the signal beam SNb and the reference beam RFa do not produce interference fringes. Also, λ1 and λ2
are different, so the incident angles Θ1 and Θ2 are also different.

On the other hand, examples of recording materials capable of multiple recording include Bi12SiO20 (BSO), Srx B
a1-x Nb2O6 (SBN), LiNbO3
Electro-optic crystals such as, semiconductor crystals such as GaP, GaAs, etc. can be used.

According to the embodiment described above, by simultaneously making the laser beams RB1 and RB2 of different wavelengths enter the ultrasonic light changer 14 driven at a constant driving frequency, the respective incident laser beams RB1 and RB2 are By using the two diffracted lights obtained from The number of multiplicities is not limited by the amplitude modulated frequency band or the numerical aperture (NA) of the objective lens. Furthermore, no time is required to switch the reference light RF, and storage speed is not significantly limited.

In the above embodiments, the laser beams from a plurality of laser light sources are not limited to being oscillated simultaneously, but a single laser beam is selectively and sequentially oscillated from a plurality of laser light sources.
It is also possible to oscillate and record over a previously recorded hologram.

Next, still another embodiment of the information recording apparatus of the present invention will be described with reference to FIGS. 6 to 8. In this embodiment, the angle of incidence of signal light and reference light, which are ultrasonic diffracted lights from an ultrasonic light deflector, on a recording medium can be controlled according to the inclination of the recording medium, and the angular resolution during multiplex recording is Multiplex recording is possible on a moving medium without being restricted by surface runout, warping, etc. of the moving medium.

In FIG. 6, reference numeral 1 denotes a recording light source, which is composed of, for example, an argon laser, a Nd:YAG laser, or the like. 14 is an ultrasonic optical deflector, and an amplitude modulator 12 to be described later.
When driven by an amplitude modulation signal AM, it generates an ultrasonic wave corresponding to the amplitude modulation signal AM. At this time, when the laser beam RB of wavelength λ is incident from the recording light source 1, the frequency components ν0 (±Δν) and ν0 −νi with a specific diffraction angle
Two diffracted lights corresponding to (±Δν) are emitted.

Reference numeral 12 denotes an amplitude modulator that amplitude-modulates the carrier signal CF with the input signal IS for amplitude modulation, and generates ν0 ±Δν, ν0-νi ±Δν (lower side wave), ν0 +νi ± as a result of this amplitude modulation. Among the frequency components of Δν (upper side wave), for example, the upper side wave is removed by a low-pass filter (not shown), and ν0 ±Δν and ν0 −νi ±Δν
outputs an amplitude modulated signal AM having a frequency component of .

A collimating lens 15 converts the diffracted light by the ultrasonic light deflector 14 into parallel light, and causes one of the diffracted lights from the ultrasonic light deflector 14 to enter the spatial light modulator 4. The spatial light modulator 4 modulates the carrier diffracted light to give two-dimensional information and outputs it as signal lights SNa and SNb.

Reference numeral 16 denotes an objective lens, which condenses the signal beams SNa and SNb produced by the spatial light modulator 4 and makes them incident on the recording medium 5 moving in a predetermined direction, and also diffracts the other beams through the collimating lens 15. The light is focused and made incident on the signal light incident area of the recording medium 5. Note that the recording medium 5 is arranged to be movable by a moving mechanism (not shown).

Reference numeral 10 denotes a carrier wave signal generator, which generates a carrier wave signal CF having a frequency ν0 ±Δν according to the input level of a tilt angle detection signal PDout to be described later. Specifically, when the recording medium 5 is not tilted and is in a horizontal state that should be used as a reference, and the tilt angle detection signal PDout is at the reference level, a carrier wave signal CF having a reference frequency ν0 is generated, and the recording medium 5 is tilted. When there is a fluctuation in the level of the tilt angle detection signal PDout, a carrier wave signal CF having a frequency ν0 ±Δν is generated by shifting the reference frequency ν0 by ±Δν according to the level of the fluctuation.

Reference numeral 11 denotes an input signal generator, which generates a frequency ν corresponding to the input level of a tilt angle detection signal PDout, which will be described later.
An input signal IS of i (≠ν0)±Δν is generated. Specifically, similar to the carrier wave signal generator 10, the recording medium 5
When the recording medium 5 is not tilted and is in a horizontal state to be used as a reference, and the tilt angle detection signal PDout is at the reference level, an input signal IS of the reference frequency νi is generated, and the recording medium 5 is tilted to the level of the tilt angle detection signal PDout. If there is a fluctuation, adjust the reference frequency νi by ±Δ according to the fluctuation level.
An input signal IS is generated with a frequency νi ±Δν shifted by ν.

As shown in FIG. 7, the carrier wave signal generator 10 includes an amplifier 101 with an amplification factor K1 and a voltage controlled oscillator 1.
On the other hand, the input signal generator 11 includes an amplifier 111 with an amplification factor of K2 and a voltage controlled oscillator 112. Each amplifier 101 and 111 receives a tilt angle detection signal P.
After receiving Dout, the amplified tilt angle detection signal PDou
Depending on the input level of t, the voltage controlled oscillator 102,1
After changing the oscillation frequency in step 12, the signals are input to the amplitude modulator 12.

In FIG. 6, reference numeral 20 denotes a laser light source for detecting inclination, which causes laser light LI to be incident on a predetermined position on the back surface 51 of the recording medium 5 at a predetermined angle.

A condensing lens 21 condenses the reflected light LR of the laser beam LI on the back surface 51 of the recording medium 5.

22 is a photodetector for position detection, for example, PS
D, reflected light L by the back surface 51 of the recording medium 5
When R enters the reference position PB, an output equivalent to the preset reference output is obtained, and when the incidence of the reflected light LR deviates from the reference position PB, a difference from the reference output according to the amount of deviation is obtained. I get an output with .

23 is a differential amplifier which inputs the two outputs of the photodetector 22, amplifies the difference between them, and generates a tilt angle detection signal PD.
It is output to the carrier wave signal generator 10 and the input signal generator 11 as out.

Next, the operation when the recording medium 5 is not kept horizontal but is tilted will be described below.

First, as shown in FIG. 8, when the recording medium 5 is at the reference position indicated by the solid line and the recording surface is kept horizontal in the left-right direction of the drawing and is not inclined, or
As shown in a, when the recording surface of the recording medium 5a is kept horizontal and not tilted when the recording medium 5a moves in parallel upward, the emitted light LI of the laser light source 20 is reflected by the back surface 51 of the recording medium 5, and its The reflected light LR or LRa is incident on the reference position PB of the position detection photodetector 22 by the condenser lens 21. As a result, the two outputs from the position detection photodetector 22 are output at the same level and input to the differential amplifier 23. Therefore, the level of the tilt angle detection signal PDout, which is the output of the differential amplifier 23, becomes zero.

Since the level of the tilt angle detection signal PDout is zero, a carrier wave signal CF having a reference frequency ν0 is generated in the carrier wave signal generator 10 and outputted to the amplitude modulator 12. Similarly, the input signal generator 11 also generates an input signal IS of the reference frequency νi, and the amplitude modulator 1
2 is output.

[0120] In the amplitude modulator 12, the carrier wave signal CF is amplitude-modulated by the input signal IS. As a result, ν0 and ν0 −νi (lower side wave), ν0 +νi (upper side wave)
frequency components are generated. Among the generated frequency components,
The upper side wave is removed by a low-pass filter (not shown), and ν0
An amplitude modulated signal AM having frequency components of ν0 - νi is output, and this is input to the ultrasonic optical deflector 14. As a result, an ultrasonic wave corresponding to this amplitude modulation signal AM is generated within the ultrasonic optical deflector 14.

[0121] In parallel with this, a laser beam LB with a wavelength λ is incident on the ultrasonic beam deflector 14 from the recording light source 1.
As a result, diffracted light S corresponding to the carrier wave signal CF and diffracted light R corresponding to the lower side wave signal are emitted from the ultrasonic light deflector 14 at different diffraction angles.

The diffracted light S enters the spatial light modulator 4, where it is given two-dimensional information and is emitted as a signal light SN. The signal light SN is condensed by the objective lens 16 and is incident on a predetermined position of the moving recording medium 5. Further, the diffracted light R converted into parallel light by the collimating lens 15 is condensed by the objective lens 16 and becomes reference light RF at an incident angle determined by the frequency νi of the input signal IS and the wavelength λ of the incident laser light LB. With this, the signal light SN enters the incident area on the recording medium 5. As a result, both the signal light SN and the reference light RF interfere with each other on the surface of the moving recording medium 5, and interference fringes due to both are recorded.

On the other hand, as shown by the reference numeral 5b in FIG. Reflected light LR on the back surface 51 of the recording medium 5 of LI
b is incident on the position detection photodetector 22 at a position shifted by a distance corresponding to the inclination angle from the reference position PB by the condenser lens 21. As a result, the position detection photodetector 22
The two outputs from the differential amplifier 2 are output at different levels.
3 is input. Therefore, the level of the tilt angle detection signal PDout which is the output of the differential amplifier 23 is not zero, but
It has a level corresponding to the inclination angle.

[0124] The tilt angle detection signal PDo at this predetermined level
ut is input to a carrier signal generator 10 and an input signal generator 11. The carrier wave signal generator 10 generates a carrier wave signal CF having a frequency ν0 ±Δν, which is obtained by shifting the reference frequency ν0 by ±Δν according to the input level of the tilt angle detection signal PDout, and outputs it to the amplitude modulator 12. Similarly, in the input signal generator 11, the reference frequency ν
An input signal IS having a frequency ν0 ±Δν, which is obtained by shifting i by ±Δν, is generated and output to the amplitude modulator 12.

In the amplitude modulator 12, the carrier wave signal CF is amplitude-modulated by the input signal IS as described above. As a result, ν0 ±Δν and ν0 −νi ±Δν (lower side wave)
, ν0 +νi ±Δν (upper side wave) frequency components are generated. Among the generated frequency components, the upper side wave is removed by a low-pass filter (not shown), and ν0 ±Δν and ν0
-νi Amplitude modulation signal AM whose frequency components are ±Δν
is output and input to the ultrasonic optical deflector 14. As a result, an ultrasonic wave corresponding to this amplitude modulation signal AM is generated within the ultrasonic optical deflector 14.

[0126] In parallel, a laser beam RB of wavelength λ is incident on the ultrasonic beam deflector 14 from the recording light source 1.
Thereby, diffracted light Sb corresponding to the carrier wave signal CF and diffracted light Rb corresponding to the lower side wave signal are emitted from the ultrasonic light deflector 14 at different diffraction angles.

These two diffracted lights Sb and Rb are converted into parallel lights after passing through the collimating lens 15, and the diffracted lights Sb and Rb are converted into parallel lights.
is input to the spatial light modulator 4, where it is given two-dimensional information and output as signal light SNb. The signal light SNb is condensed by the objective lens 16 and is incident on a predetermined position of the moving recording medium 5. Further, the diffracted light Rb converted into parallel light by the collimating lens 15 is subjected to a condensing action by the objective lens 16 and becomes reference light RF, which is determined by the frequency νi ±Δν of the input signal IS and the wavelength λ of the incident laser light RB. The signal light SN is incident on the incident area of the recording medium 5 at an incident angle. As a result, both the signal light SNb and the reference light RFb interfere with each other on the surface of the moving recording medium 5, and interference fringes due to both are recorded.

As described above, according to this embodiment, the diffracted lights S and R by the ultrasonic optical deflector 2, that is, the signal light S
Since the direction of incidence of the N and reference beam RF onto the recording medium 5 can be controlled according to the inclination of the recording medium 5, the angular resolution during multiplex recording is limited by surface runout, warpage, etc. of the movable recording medium 5. Never. Therefore, there is an advantage that a large capacity storage device can be realized.

[0129]

As described above, in the information recording device of the present invention, the laser beam obtains two diffracted beams due to the Doppler effect due to the traveling ultrasonic wave by the ultrasonic beam deflection means,
Since the frequency shift amounts of the carrier wave diffracted light and the lower side wave diffracted light are different, interference fringes caused by interference of these diffracted lights move relative to the recording medium. Therefore, by continuously moving the medium in the direction of the ultrasonic wave at the same speed as the movement speed of the interference fringes on the recording medium surface,
The interference fringes can be made relatively stationary on the recording medium. Therefore, hologram recording can be performed on a medium that moves at a constant speed, and high speed can be achieved. Furthermore, by switching the amplitude modulation frequency to a different frequency, only the diffraction angle of the lower side wave diffracted light can be changed, and as a result, the incident angle of the reference light onto the recording medium surface can be changed, making multiplex recording possible. , high density recording can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the basic configuration of an information recording device that is an embodiment of the present invention.

FIG. 2 is a diagram illustrating the operation of the apparatus of the present invention shown in FIG. 1 to perform multiplex recording.

FIG. 3 is a block diagram showing a configuration for performing multiplex recording at high speed using a plurality of diffraction light modulation means, which is another embodiment of the apparatus of the present invention.

FIG. 4 is a diagram showing the relationship between the formation time of each information pattern of a plurality of diffraction light modulation means and the switching timing of the amplitude modulation frequency for the ultrasonic light deflection means in the apparatus of the present invention shown in FIG. 3;

FIG. 5 is another embodiment of the device of the present invention, in which a plurality of laser beams having different wavelengths are input simultaneously or sequentially, thereby generating respective signal beams and reference beams obtained by inputting the respective laser beams. FIG. 2 is a block diagram showing a configuration that allows multiplex recording to be performed at the same time.

FIG. 6 is a block diagram showing a configuration capable of compensating for surface runout and warpage that occur when a recording medium moves, which is still another embodiment of the wavelength of the present invention.

7 is a diagram showing the respective configurations of a carrier signal generator and an input signal generator in the apparatus of the present invention shown in FIG. 6. FIG.

FIG. 8 is an explanatory diagram of an operation for detecting a tilt angle of a recording medium in the apparatus of the present invention shown in FIG. 6;

[Explanation of symbols]

1 Light source 12 Amplitude modulator 14 Ultrasonic optical deflector 4 Spatial light modulator 5 Recording medium

Claims (7)

[Claims] 1. A recording light source that emits a laser beam; a carrier wave signal generating means that generates a carrier wave signal of a predetermined frequency;
input signal generating means for generating an input signal for amplitude modulation having a frequency different from the frequency of the carrier wave signal; and the input signal generating means is connected to the carrier wave signal generating means and the input signal generating means, and amplitude modulation means that performs amplitude modulation; and an ultrasonic light deflector that is connected to the amplitude modulation means, receives laser light from the recording light source, and diffracts the laser light in two directions by an amplitude modulation signal from the amplitude modulation means. and the ultrasonic light deflection means,
a diffracted light modulating means for imparting predetermined information to the diffracted light of a laser beam diffracted in one direction and modulating it into a signal light; a signal light from the diffracted light modulating means; and the ultrasonic light deflecting means The reference beam, which is the diffracted beam of the laser beam diffracted in a direction different from that of the signal beam, is irradiated onto the same incident area.
An information recording device comprising a movable recording medium means for performing interference recording of both. 2. The ultrasonic light deflecting means receives a laser beam at a constant angle of incidence from the recording light source, and generates a carrier wave that is diffracted in one direction by a switchable amplitude modulation signal from the amplitude modulation means. The recording medium means generates diffracted light and sidewave diffracted light diffracted in a direction different from the diffracted light, and the recording medium means
Claim 1, wherein the plurality of sidewave diffracted lights having different diffraction angles are incident as a plurality of reference lights having different incident angles, and multiplex recording is performed by interference with the signal light diffracted in one direction. Information recording device as described in section. 3. The information recording apparatus according to claim 2, wherein the switchable amplitude modulation signal is obtained by switching the frequency of the amplitude modulation input signal. 4. The information recording apparatus according to claim 2, wherein the switched amplitude modulation signals having a plurality of different frequencies are obtained by switching the frequency of the carrier wave signal itself generated from the carrier wave signal means. 5. The ultrasonic light deflection means receives a single light beam from the recording light source and is diffracted in multiple directions by a switchable amplitude modulation signal from the amplitude modulation means. generating a plurality of carrier wave diffraction lights with different carrier wave diffraction lights and one lower side wave diffraction light diffracted in one direction corresponding to each of the carrier wave diffraction lights of the plurality of carrier wave diffraction lights, and the diffraction light modulation means comprises a plurality of diffracted light modulating means provided corresponding to the plurality of carrier wave diffracted lights having different diffraction angles; The information is received by each of the modulation means, and the signals are modulated and incident as a plurality of signal beams with different incident angles, and due to interference with the reference beam, which is the lower side wave diffracted beam diffracted in one direction, the signal beams are transmitted to the moving recording medium. The information recording device according to claim 1, wherein multiple recording is performed. 6. The recording light source that emits the laser beam,
The ultrasonic light deflection means is composed of a plurality of laser light sources each having a different wavelength, and the ultrasonic light deflection means has a diffraction angle determined by the frequency of the amplitude modulation signal from the amplitude modulation means and a predetermined wavelength of the laser light from the laser light source, The light beam is diffracted in two directions, carrier wave diffraction light and lower side wave diffraction light, and the diffraction light modulation means includes a plurality of diffraction light modulation means provided corresponding to carrier wave diffraction light determined for each laser beam of a different wavelength. The recording medium means receives a signal beam and a reference beam incident at an incident angle determined for each laser beam having a different wavelength from the laser light source into the same recording area, and causes interference to occur on the moving recording medium. 2. The information recording apparatus according to claim 1, wherein multiple recording is performed. 7. Recording medium tilt angle detection means for detecting a tilt angle of the recording medium means with respect to a reference position and outputting a corresponding detection signal, connected to the carrier wave signal generation means and the input signal generation means. , a frequency obtained by shifting a reference frequency corresponding to a reference position of the recording medium means of each of the carrier wave signal generation means and the input signal generation means according to the tilt angle detected by the tilt angle detection means; A carrier wave signal and an input signal are generated from the carrier wave signal generating means and the input signal generating means, and thereby the angle of incidence of the signal light and the reference light, which are the diffracted lights, on the recording medium means is adjusted to the inclination angle. The information recording device according to claim 1, further comprising means for controlling accordingly.