JP2010238306A - Cartridge storage type hologram recording medium, and recording and reproducing device of cartridge storage type hologram recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cartridge storage type hologram recording medium which can be made small the cartridge storage type hologram recording medium, and which can reduce noises of a recording signal and suppressing reduction of recording capacity by suppressing caused stray light. <P>SOLUTION: The cartridge storage type hologram recording medium 1 comprises: a disk type hologram recording medium 4; a case 2 housing the disk type hologram recording medium 4 inside freely rotatably while shielding the light so that external light does not enter inside; a case opening part 5 provided at the case 2 so that projection light can be incident or emitted on the front and back surfaces of the disk type hologram recording medium 4; and a shutter 3 opening the case opening part 5 if write-in or read-out is performed using the projection light for the disk type hologram recording medium 4, and otherwise closing the case opening part 5. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a cartridge-containing hologram recording medium used for recording and reproducing information using hologram technology, and a recording / reproducing apparatus for the cartridge-containing hologram recording medium.

  In recent years, hologram recording / reproducing apparatuses that record and reproduce large-capacity information using hologram technology have been proposed. In the hologram recording / reproducing apparatus, signal light including information and reference light not including information are generated from the same laser light, and these are irradiated to the same portion of the hologram recording medium.

  Then, the signal light and the reference light interfere with each other on the hologram recording medium, so that a diffraction grating (hologram) is formed at the irradiated position and is recorded on the medium. That is, the hologram recording medium formed of the monomer is polymerized by forming a diffraction grating, whereby recording on the medium is performed.

  When the hologram recorded in this way is irradiated with only reference light, diffracted light (reproduced light) is generated. This reproduction light includes information that the signal light at the time of recording has. Therefore, information can be reproduced by the light receiving element receiving this reproduction light.

  In the above-described hologram recording medium, a technique called multiplex recording is used to record a large amount of information on the hologram recording medium. This multiplex recording is a method of recording a plurality of holograms in the same location (or overlapping area) of the hologram recording medium. Various methods such as angle multiplexing, shift multiplexing, rotation multiplexing, and wavelength multiplexing have been proposed as the multiplexing recording method.

  The hologram recording medium used for recording as described above has been developed so that more information can be recorded on the photosensitive material used as the recording layer of the hologram recording medium.

  For this hologram recording medium, since the recording layer of this hologram recording medium is photosensitive, in order to have portability in an unrecorded state, it must be stored in a light-shielding cartridge. Proposals have been made (see, for example, Patent Document 1).

  In Patent Document 1, a recording medium is housed in a cartridge as a hologram recording medium, and a window for allowing signal light and reference light to enter during recording is provided on the surface of the cartridge, and a window for emitting reproduction light during reproduction is provided on the cartridge. A cartridge-containing holographic recording medium having a configuration provided on the back surface of the recording medium is described.

JP-A-2005-302220

  By the way, as described above, in the cartridge storage hologram recording medium described in Patent Document 1, a window is provided on the surface of the cartridge in order to allow the signal light and the reference light to enter the cartridge.

  However, in this cartridge-containing holographic recording medium, it is necessary to increase the shape of the window when the incident angles of the reference light and the signal light are larger than those of the recording medium.

  Therefore, in this cartridge storage type hologram recording medium, it is necessary to make the outer shape of the cartridge for storing the disk type hologram recording medium considerably larger than the outer shape of the disk type hologram recording medium. There arises a problem that convenience for handling the hologram recording medium is impaired.

  In addition, since the shape of the window provided on the surface of the cartridge becomes large, the signal light incident at the time of recording or the unnecessary light generated by reflecting the reference light on the medium surface or in the medium becomes stray light in the cartridge housing, This stray light causes useless consumption of the monomer that causes the hologram recording medium formed of the monomer to be polymerized.

  For this reason, the consumption of the monomer causes the recording quality of the cartridge-containing hologram recording medium to deteriorate, which causes an increase in the noise of the reproduction signal and a decrease in the recording capacity.

  Therefore, the present invention has been made to cope with the above-described situation, and it is possible to reduce the size of the cartridge-containing holographic recording medium, and to suppress the generated stray light and reduce the noise of the recording signal. It is an object of the present invention to provide a cartridge-housing hologram recording medium and a recording / reproducing apparatus for the cartridge-housing hologram recording medium that can suppress the lowering and the recording capacity.

  First, the cartridge storage type hologram recording medium of the present invention will be described. The cartridge-containing holographic recording medium of the present invention is characterized by including a disc-shaped holographic recording medium, a casing, a casing opening, and a shutter.

  That is, in the above-described cartridge storage type hologram recording medium, the casing stores the disk type hologram recording medium in a rotatable manner. In addition, this casing is shielded so that outside light does not enter the inside. The housing opening is provided in the housing, and is formed on the front and back surfaces of the disc-type hologram recording medium so that projection light can enter or exit.

  In addition, the above-described cartridge-accommodating hologram recording medium includes a shutter that opens the casing opening when writing or reading is performed using projection light, and closes the casing opening at other times.

  The shutter has a function of opening the casing opening when writing or reading with respect to the disk-type hologram recording medium using the projection light, and closing the casing opening at other times. Yes.

  Therefore, when writing or reading is not performed, the casing opening can be closed by this shutter, so that incident light into the casing can be suppressed. Therefore, useless consumption of monomer during writing can be suppressed, and noise reduction and recording capacity reduction of the recording signal can be suppressed.

  In the cartridge-containing holographic recording medium, the housing opening is preferably formed along the radial direction of the disc-type holographic recording medium. Further, it is preferable that the housing opening is formed so that the projection light can reach the outer peripheral edge of the disk-type hologram recording medium.

  According to the above-described cartridge storage type hologram recording medium, the housing opening is formed so that the projection light can reach the outer peripheral end of the disk type hologram recording medium. Therefore, it is possible to increase the recording capacity of the cartridge storage hologram recording medium.

  In addition, the cartridge that is a housing for housing the disk-type hologram recording medium can be made small, and the convenience for handling the cartridge-containing hologram recording medium can be improved.

  Further, the downsizing can improve the rigidity of the housing and improve the vibration resistance. Thereby, the vibration of the disc-type hologram recording medium can be suppressed, and the fluctuation of the interference fringes of the recording signal generated by this vibration can be reduced.

  Further, in the above-described cartridge storage type hologram recording medium, the housing opening may be formed by opening the outer edge of the housing opening. By doing so, the shape of the cartridge, which is a housing for housing the disk-type hologram recording medium, is simplified, and the formation cost of the cartridge-containing hologram recording medium can be reduced.

  Or you may make it form the housing | casing bridge | crosslinking bar | burr which obstruct | occludes a housing | casing opening part along this outer edge end in the outer edge end of the housing | casing of said cartridge accommodation type hologram recording medium. By doing in this way, the rigidity of a housing | casing improves and the thickness of a housing | casing can be made thin. Moreover, vibration resistance can be improved. Thereby, the vibration of the disc-type hologram recording medium can be suppressed, and the fluctuation of the interference fringes of the recording signal generated by this vibration can be reduced.

  Moreover, in the above-described cartridge storage type hologram recording medium, it is preferable to form the shutter as follows. That is, the shutter is configured to cover the casing opening so as to be slidable along the outer edge of the casing and close the casing opening.

  In addition, the shutter includes a shutter opening that can expose the entire housing opening to the outside, and by sliding the shutter so that the shutter opening exposes the entire housing opening to the outside, The housing opening is opened.

  By doing so, the configuration of the shutter can be simplified, and the opening and closing of the housing opening of the cartridge storage type hologram recording medium can be smoothly performed.

  With respect to the shutter, the shutter opening may be formed so that the outer edge of the shutter opening is open. By doing so, the shape of the shutter of the housing for housing the disk-type hologram recording medium is simplified, and the formation cost of the cartridge-containing hologram recording medium can be reduced.

  Further, in the cartridge-containing hologram recording medium provided with the shutter, a shutter bridging bar that closes the shutter opening along the outer edge may be formed at the outer edge of the shutter.

  By doing in this way, the rigidity of a shutter can improve and vibration resistance can be improved. Thereby, the vibration of the disc-type hologram recording medium can be suppressed, and the fluctuation of the interference fringes of the recording signal generated by this vibration can be reduced.

  Next, the recording / reproducing apparatus for the cartridge-containing hologram recording medium of the present invention will be described. The recording / reproducing apparatus for a cartridge-contained hologram recording medium according to the present invention is a recording / reproducing apparatus for a cartridge-contained hologram recording medium in which writing or reading is performed using projection light on any of the cartridge-contained hologram recording media described above. is there.

  The above-described recording / reproducing apparatus for cartridge-contained hologram recording medium has a writing locus of the optical axes of reference light and signal light, which are projection light used for writing to the cartridge-contained hologram recording medium. Is formed so as to coincide with the radial direction of the cartridge-containing hologram recording medium.

  For this reason, this cartridge-contained hologram recording medium recording / reproducing apparatus performs writing and reading to and from a disk-type hologram recording medium having a housing opening formed along the radial direction of the disk-type hologram recording medium. Can be done smoothly.

  Moreover, the recording / reproducing apparatus for the cartridge-housing hologram recording medium of the present invention for writing or reading to any one of the cartridge-housing hologram recording media using the projection light can be configured as follows. it can.

  That is, the reference light, which is one of the projection lights used for writing on the cartridge-housing hologram recording medium, has an optical axis of the reference light that is changed from the outer circumference side to the inner circumference side of the cartridge-housing hologram recording medium. The recording / reproducing apparatus for the cartridge-contained hologram recording medium is formed by irradiating the cartridge-contained hologram recording medium so as to face the head.

  By doing in this way, the conjugate mirror used when reading a cartridge storage type hologram recording medium can be arranged on the inner circumference side of the cartridge storage type hologram recording medium. Therefore, the recording / reproducing apparatus for the cartridge-containing hologram recording medium can be downsized.

  According to the present invention, the cartridge-containing holographic recording medium includes a shutter that opens the housing opening when writing or reading using the projection light and closes the housing opening at other times. Yes.

  Therefore, when writing or reading is not performed, the shutter opening can be closed by this shutter, so that generation of stray light in the housing can be suppressed. Therefore, useless consumption of monomer during writing can be suppressed, and noise reduction and recording capacity reduction of the recording signal can be suppressed.

  In addition, since the housing opening of the cartridge-containing hologram recording medium is formed so that the projection light can reach the outer peripheral edge of the disk-type hologram recording medium, the cartridge is a housing that houses the disk-type hologram recording medium. Can be reduced.

  Therefore, the recording capacity of the recording medium can be increased and the convenience for handling the cartridge-containing holographic recording medium is improved. Further, the downsizing can improve the rigidity of the housing and improve the vibration resistance. Thereby, the vibration of the disc-type hologram recording medium can be suppressed, and the fluctuation of the interference fringes of the recording signal generated by this vibration can be reduced.

  In addition, a case bridging bar that closes the case opening along the outer edge is formed at the outer edge of the cartridge-containing hologram recording medium, so that the rigidity of the case is improved and vibration resistance is improved. can do. Thereby, the vibration of the disc-type hologram recording medium can be suppressed, and the fluctuation of the interference fringes of the recording signal generated by this vibration can be reduced.

  Further, the shutter of the cartridge-containing hologram recording medium has a shutter opening that can expose the entire housing opening, and a shutter that closes the shutter opening along the outer edge at the outer edge of the shutter. A bridge bar is formed.

  Therefore, the rigidity of the shutter can be improved and the vibration resistance can be improved. Thereby, the vibration of the disc-type hologram recording medium can be suppressed, and the fluctuation of the interference fringes of the recording signal generated by this vibration can be reduced.

It is the perspective view which showed the external appearance of the surface of the cartridge storage type hologram recording medium in this Embodiment. It is the perspective view which showed the external appearance of the back surface of the cartridge storage type hologram recording medium in this Embodiment. It is sectional drawing of the disk type hologram recording medium of the cartridge storage type hologram recording medium in this Embodiment. It is the top view which looked at the surface of the disc type hologram recording medium of the cartridge accommodation type hologram recording medium in this Embodiment from the top. (A) is a front view showing the front surface, (b) is a side view, and (c) is the back surface of the cartridge-containing hologram recording medium in the present embodiment in a state where the shutter is removed. It is a rear view. It is a perspective view of the cartridge of the cartridge storage type hologram recording medium in the present embodiment. FIG. 5A is a front view showing the front surface, FIG. 5B is a side view, and FIG. 5C is a rear view showing the back surface of the shutter of the cartridge storage hologram recording medium in the present embodiment. . It is a perspective view of the shutter of the cartridge storage type hologram recording medium in the present embodiment. It is the perspective view seen from the surface in the state which opened the shutter of the cartridge storage type hologram recording medium in this Embodiment. It is the perspective view seen from the back surface in the state which opened the shutter of the cartridge storage type hologram recording medium in this Embodiment. FIG. 3 is a perspective view showing a state where a cartridge-housing hologram recording medium is mounted on a carriage provided in a recording / reproducing apparatus for a cartridge-housing hologram recording medium in the present embodiment. It is explanatory drawing (the 1) which showed the structure and operation | movement of the optical system mechanism of the recording / reproducing apparatus of the cartridge storage type hologram recording medium in this Embodiment. It is explanatory drawing (the 2) which showed the structure and operation | movement of the optical system mechanism of the recording / reproducing apparatus of the cartridge accommodation type hologram recording medium in this Embodiment. It is the elements on larger scale of FIG. It is the elements on larger scale of FIG. It is a perspective view of the cartridge of the cartridge accommodation type hologram recording medium of the other example (the 1) in this embodiment. FIG. 10 is an enlarged perspective view of the vicinity of a cartridge opening in a state in which a shutter of a cartridge storage type hologram recording medium of another example (part 1) in the present embodiment is opened. It is a perspective view of the shutter of the cartridge storage type hologram recording medium of the other example (the 2) in this embodiment. FIG. 10 is an enlarged perspective view of the vicinity of a cartridge opening in a state where a shutter of a cartridge-housing hologram recording medium of another example (part 2) in the present embodiment is opened.

  Next, a cartridge storage hologram recording medium and a cartridge storage hologram recording medium recording / reproducing apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

  The cartridge storage type hologram recording medium is a medium for writing and reading a large amount of information using hologram technology.Writing and reading information on the cartridge storage type hologram recording medium are: This is performed by a recording / reproducing apparatus for a cartridge-contained hologram recording medium.

  First, the cartridge storage hologram recording medium in the embodiment of the present invention will be described. FIG. 1 is a perspective view showing the outer appearance of the front surface of the cartridge-housing hologram recording medium 1 according to the present embodiment, and FIG. 2 is a perspective view showing the outer appearance of the back surface thereof.

  1 and 2, a cartridge storage type hologram recording medium 1 is slidable into a square plate-like cartridge 2, a disc-like disk type hologram recording medium 4 built in the cartridge 2, and the cartridge 2. The shutter 3 is attached to the shutter.

  3 is a cross-sectional view of the disk-type hologram recording medium 4, and FIG. 4 is a plan view of the surface of the disk-type hologram recording medium 4 as viewed from above. 3 and 4, the disc-type hologram recording medium 4 has a disc shape as described above, and has a disc-like transparent substrates 4a and 4b and a disc-like sandwiched between the transparent substrates 4a and 4b. The recording medium 4c and a cylindrical hub 4d formed of a magnetic material at the center are configured.

  The transparent substrates 4a and 4b and the recording medium 4c constituting the disc-type hologram recording medium 4 have a thickness of 1 mm for the transparent substrates 4a and 4b and 1.5 mm for the recording medium 4c, for example.

  FIG. 5 is a three-side view showing the cartridge-containing holographic recording medium 1 with the shutter 3 removed, where (a) is a front view showing the surface thereof, (b) is a side view thereof, and (C) is the rear view which showed the back surface. FIG. 6 is a perspective view showing the cartridge 2 of the cartridge-containing holographic recording medium 1.

  5 and 6, the cartridge 2 is a rectangular plate having four sides as described above, and a space for accommodating the disk-type hologram recording medium 4 is formed therein, and inside this, As described above, the disk-type hologram recording medium 4 is rotatably accommodated. Further, the cartridge 2 is shielded from light so that external light does not enter the internal space in which the disc-type hologram recording medium 4 is accommodated.

  The cartridge 2 has a slit-like cartridge opening (from the above-described housing opening) that extends from the center of one of the four sides to the center of the cartridge 2 in parallel to two sides adjacent to the four sides. Part) 5 is formed.

  Therefore, the longitudinal direction of the slit in the slit-shaped cartridge opening 5 coincides with the radial direction of the disk-shaped disc-type hologram recording medium 4 accommodated in the internal space of the cartridge 2. In other words, the cartridge opening 5 of the cartridge storage type hologram recording medium 1 is formed along the radial direction of the disk-shaped disc type hologram recording medium 4. The width of this slit is 3 mm, for example.

  Further, as described above, the cartridge opening 5 has a slit shape, and thus the outer edge of the cartridge opening 5 is in an open state. Therefore, as will be described later, when the disc type hologram recording medium 4 is mounted on the recording / reproducing apparatus, the reference light or signal light incident from the cartridge surface opening surface 5a of the cartridge opening 5 is converted into the disc type hologram. It can reach the outer peripheral edge of the recording medium 4.

  Further, the cartridge 2 has a circular cartridge circular opening surface 5 a formed near the center of the back surface of the cartridge 2 in the back of the cartridge opening 5. The back surface side of a cylindrical hub 4d formed at the center of the disc-type hologram recording medium 4 is inserted into the cartridge-shaped opening surface 5a, so that the cartridge-shaped opening surface 5a becomes a circle serving as a rotation axis. It plays the role of a rotating shaft guide for the columnar hub 4d. By this mechanism, the disc-type hologram recording medium 4 can be rotated.

  FIG. 7 is a three-side view showing the shutter 3 of the cartridge-containing holographic recording medium 1, (a) is a front view showing the surface thereof, (b) is a side view thereof, and (c) is a side view thereof. It is the rear view which showed the back surface. FIG. 8 is a perspective view showing the shutter 3.

  7 and 8, the shutter 3 is formed by bending a thin plate into a U shape, and has a square shape with four sides. As described above, the shutter 3 is formed by bending a metal plate, but may be formed of a molded product.

  The shutter 3 is formed to be slidable along the outer edge of the cartridge 2 on the side where the cartridge opening 5 is provided. That is, the back surface of the side surface of the shutter 3 is in contact with the surface of the side surface of the cartridge 2, and the shutter 3 slides on the side surface of the cartridge 2 along the side surface of the cartridge 2.

  Like the cartridge 2, the shutter 3 is a slit-like shutter opening that extends from the center of one of the four sides to the center of the cartridge 2 in parallel with two sides adjacent to the four sides. Part 6 is formed.

  The slit-shaped shutter opening 6 is formed so that the entire cartridge opening 5 can be exposed to the outside when the shutter opening 6 overlaps the cartridge opening 5.

  Therefore, the direction of the slit in the slit-shaped shutter opening 6 is parallel to the radial direction of the disk-shaped disk-type hologram recording medium 4 accommodated in the internal space of the cartridge 2. Further, the width of the slit is slightly larger than the width of the cartridge opening 5 and is, for example, 4 mm.

  Further, similarly to the cartridge 2, a circular shutter back surface opening surface 6 a is formed in the shutter 3 near the center of the back surface of the shutter 3 at the back of the shutter opening 6. The shutter circular opening surface 6a is formed such that the diameter of the circular opening surface of the shutter circular opening surface 6a is slightly larger than the diameter of the cartridge circular opening surface 5a.

  The shutter circular opening surface 6a is in a state of overlapping with the cartridge circular opening surface 5a when the shutter opening 6 overlaps with the cartridge opening 5. Therefore, under this state, the back surface of the cylindrical hub 4d formed at the center of the disc-type hologram recording medium 4 has a cartridge circular opening surface 5a and a shutter circular opening surface 6a as shown in FIG. It is exposed to the outside through. However, normally, the cartridge circular opening surface 5a is covered with the back surface of the shutter 3, as shown in FIG.

  As shown in FIGS. 1 and 2, the shutter 3 is a spring (not shown) so that the shutter 3 normally exists at a position covering the entire cartridge opening 5 and the cartridge circular opening surface 5a. And is attached to the cartridge 2.

  From the state shown in FIGS. 1 and 2 in which the cartridge opening 5 is covered with the shutter 3 and the cartridge opening 5 is closed, the shutter 3 is slid in the direction of the arrow as shown in FIGS. The shutter 3 is mounted on the cartridge 2 so that the shutter 3 stops in a state where the shutter opening 6 overlaps the cartridge opening 5.

  When the shutter 3 slides and the shutter opening 6 overlaps the cartridge opening 5, as described above, the entire cartridge opening 5 and the cartridge circular opening surface 5a are exposed to the outside. It becomes a state.

  Further, as will be described later, when the cartridge-type hologram recording medium 1 is used with the disk-type hologram recording medium 4 mounted in the recording / reproducing apparatus and the shutter 3 opened, as described above, The back surface of the cylindrical hub 4d formed at the center of the disc-type hologram recording medium 4 is exposed to the outside through the cartridge circular opening surface 5a and the shutter circular opening surface 6a.

  Therefore, the back surface of the hub 4d of the disc-type hologram recording medium 4 exposed to the outside is attracted by a magnet provided in a rotation drive mechanism provided in a recording / reproducing apparatus for a cartridge-containing hologram recording medium. As a result, the disk-type hologram recording medium 4 accommodated in the cartridge-accommodating hologram recording medium 1 rotates.

  Next, a recording / reproducing apparatus (hereinafter referred to as a recording / reproducing apparatus) for a cartridge-contained hologram recording medium according to an embodiment of the present invention will be described. FIG. 11 is a perspective view showing a state where the cartridge-containing hologram recording medium 1 is mounted on the carriage 41 provided in the recording / reproducing apparatus 10. FIG. 11 shows the carriage 41 as viewed from the bottom side.

  In FIG. 11, the carriage 41 is in the form of a horizontal plate provided with concave portions 41b having fork end portions 41a facing each other at both front ends. A rotation drive mechanism 42 is provided at the back center of the recess 41b. The rotation drive mechanism 42 incorporates a motor (not shown), and a magnet is provided on the upper surface of the rotation shaft of the motor.

  In the recording / reproducing apparatus 10 described above, the above-described cartridge storage type hologram recording medium 1 is placed on the upper surface of the carriage 41 and fixed to the carriage 41 by a fixing mechanism (not shown).

  Simultaneously with this fixing, the shutter 3 of the cartridge storage hologram recording medium 1 is slid and opened by a shutter drive mechanism (not shown), and the cartridge storage hologram recording medium 1 is in the state shown in FIGS. At the same time, the back surface of the hub 4d of the disk-type hologram recording medium 4 built in the cartridge-containing hologram recording medium 1 is attracted to the magnet of the rotation shaft of the motor of the rotation drive mechanism 42. In this state, when the motor of the rotation drive mechanism 42 rotates, the disc type hologram recording medium 4 rotates.

  An optical system mechanism 11 (described later) of the recording / reproducing apparatus 10 is mounted above and below the concave portion 41b of the carriage 41. Then, the projection light emitted from the optical system mechanism 11 is stored in the cartridge-containing hologram recording medium 1 via the cartridge opening 5 and the shutter opening 6 of the disk hologram recording medium 4. Is projected onto the hologram recording medium 4.

  Further, the carriage 41 is in the same direction as the longitudinal direction of the slit of the cartridge opening 5 of the cartridge 2 with respect to the optical system mechanism 11, that is, the disc type hologram recording medium 4 built in the cartridge containing hologram recording medium 1. Are moved from the inner circumference side toward the outer circumference side of the disc type hologram recording medium 4 along the radial direction.

  12 and 13 are explanatory diagrams showing the configuration and operation of the optical system mechanism 11 of the recording / reproducing apparatus 10. Among these, FIG. 12 is an explanatory diagram showing a case where recording is performed, that is, a case where writing is performed on the cartridge-housing hologram recording medium 1, and FIG. It is explanatory drawing which showed the case where reading is performed.

  As shown in FIGS. 12 and 13, the optical system mechanism 11 of the recording / reproducing apparatus 10 includes a laser light source 20, a collimator unit 21, a recording shutter 22, a beam separation unit 23, a deflection mirror 24, a relay lens 25, a polarization beam splitter ( PBS) 26, aperture 27, objective lens 28, conjugate mirror 29, imaging device 30, and reflective liquid crystal spatial modulation device 31.

  In FIGS. 12 and 13, only the disc-type hologram recording medium 4 built in the cartridge-containing hologram recording medium 1 is shown. However, in practice, the disk-type hologram recording medium 4 is built in the cartridge 2 of the disk-type hologram recording medium 4, and the disk-type hologram recording medium 4 is placed on the carriage 41 of the recording / reproducing apparatus 10. Has been moved.

  In FIGS. 12 and 13, the left direction toward these figures is the outer peripheral side of the disc-type hologram recording medium 4, and the right direction is the inner peripheral side. Accordingly, in FIGS. 12 and 13, the disc-type hologram recording medium 4 moves from right to left.

  Next, a case where recording, that is, writing in the optical system mechanism 11 of the recording / reproducing apparatus 10 will be described. When this writing is performed, the reference light RL and the signal light SL are the above-described projection light emitted from the optical system mechanism 11.

  In FIG. 12, the light emitted from the laser light source 20 becomes parallel light by the collimator unit 21 including the recording shutter 22. The parallel light is separated into reference light RL and signal light SL by the beam separation unit 23.

  The reference light RL is reflected by the deflecting mirror 24, passes through the relay lens 25, and is irradiated on the disc type hologram recording medium 4. The deflection mirror 24 is variable in angle and is driven during recording and reproduction.

  The signal light SL that travels straight through the beam separation unit 23 and is emitted from the beam separation unit 23 is enlarged in beam diameter, passes through the polarization beam splitter (PBS) 26, and enters the reflective liquid crystal spatial modulation element 31. .

  The reflective liquid crystal spatial modulation element 31 spatially modulates the signal light SL. The light reflected from the reflective liquid crystal spatial modulation element 31 is reflected by the PBS 26, passes through the aperture 27, is condensed on the objective lens 28, and is irradiated onto the disc type hologram recording medium 4.

  The signal light SL and the reference light RL are overlapped in the disc hologram recording medium 4, and as a result, interference fringes are generated. The light intensity component of the interference fringes is transferred to the disc hologram recording medium 4. As recorded.

  Further, the amount of the outgoing beam irradiated to the disc type hologram recording medium 4 is varied by the recording shutter 22, and the reference beam RL having a different angle is irradiated by the deflecting mirror 24. Multiple holograms can be recorded.

  Next, a case where reproduction, that is, reading in the optical system mechanism 11 of the recording / reproducing apparatus 10 will be described. When performing this reading, the reference light CRL is the above-described projection light emitted from the optical system mechanism 11. In addition, about the part which overlaps with said description, description is abbreviate | omitted.

  In FIG. 13, only the reference light CRL is separated from the light emitted from the laser light source 20 by the beam separation unit 23. The separated reference light CRL is reflected by the deflection mirror 24, passes through the relay lens 25, and is irradiated onto the disc-type hologram recording medium 4.

  Then, the light transmitted through the disk type hologram recording medium 4 is reflected by the conjugate mirror 29 on which the quarter wavelength plate 29a is mounted, and is irradiated again on the disk type hologram recording medium 4.

  Due to the light irradiating the disc-type hologram recording medium 4 again, the reproduction light CL including the reproduction signal is transmitted through the objective lens 28 and forms an image on the image sensor 36. In this case, all the recorded signals can be reproduced by changing the angle of incidence on the disc-type hologram recording medium 4 and changing the angle of the conjugate mirror 29 by the deflection mirror 24.

  Next, the above-described recording state and reproducing state will be described in more detail. First, at the time of recording, FIG. 14 is an enlarged partial enlarged view of the vicinity of the cartridge storage hologram recording medium 1 irradiated with the reference light RL and the signal light SL in FIG. 12 showing the state at the time of recording.

  In FIG. 14, the relative movement trajectories of the optical axis of the reference light RL and the signal light SL with respect to the cartridge-housing hologram recording medium 1 are the radial direction of the disk-type hologram recording medium 4 and the cartridge opening 5 in the cartridge 2. And the direction parallel to the longitudinal direction of the slit of the shutter opening 6 in the shutter 3.

  The reference beam RL has a beam diameter of, for example, φ2 mm, and is written on the disc-type hologram recording medium 4 by changing the deflection angle within a range of, for example, an incident angle of 40 ° to 70 °.

The signal light SL is collected by the objective lens 28 having a beam diameter of φ19 mm and an aperture ratio NA of 0.6, and is incident on the disc-type hologram recording medium 4 at an incident angle of 55 ° of the optical axis. At this time, the conjugate mirror 29 is retracted to a position where it is not irradiated with the reference light RL and the signal light SL.
FIG. 15 is an enlarged partial enlarged view of the vicinity of the cartridge storage hologram recording medium 1 irradiated with the reference light CRL in FIG. 13 showing the state during reproduction. In FIG. 15, the reference light CRL has a beam diameter of φ2 mm, for example, is incident on the disc-type hologram recording medium 4 so that the incident angle during recording is in the vicinity of 40 ° to 70 °, and is reflected by the conjugate mirror 29. The incident light is again incident on the disc-type hologram recording medium 4.

  The light re-entering the disc type hologram recording medium 4 emits the reproduction light CL from the disc type hologram recording medium 4. The emitted reproduction light CL enters the objective lens 28 and enters the image sensor 36. Incident.

  As can be seen from FIGS. 12 to 15, in the optical system mechanism 11 of the recording / reproducing apparatus 10, the optical axis of the reference light RL or the reference light CRL is built in the cartridge storage hologram recording medium 1. The optical system mechanism 11 is arranged so as to face from the outer peripheral side to the inner peripheral side of the disc type hologram recording medium 4 that is being used.

  Therefore, in this optical system mechanism 11, the conjugate mirror 29 is arranged on the inner peripheral side of the disc-type hologram recording medium 4 as shown in FIGS. 12 to 15.

  According to the cartridge storage hologram recording medium 1 described above, when writing or reading is performed using the projection light, the cartridge opening 5 in the cartridge 2 of the cartridge storage hologram recording medium 1 is opened, and otherwise A shutter 3 for closing the cartridge opening 5 is provided.

  Therefore, when writing or reading is not performed, the cartridge opening 5 can be closed by the shutter 3, so that the generation of stray light in the cartridge 2 can be suppressed. Therefore, useless consumption of monomer during writing can be suppressed, and noise reduction and recording capacity reduction of the recording signal can be suppressed.

  Further, the cartridge opening 5 is formed so that the projection light can reach the outer peripheral end of the disc type hologram recording medium 4 built in the cartridge containing hologram recording medium 1. For this reason, the recording capacity of the cartridge-containing holographic recording medium 1 can be increased.

  Further, the cartridge 2 that is a housing for housing the disc-type hologram recording medium 4 can be made small, and the convenience for handling the cartridge-containing hologram recording medium 1 can be improved.

  Further, the downsizing improves the rigidity of the cartridge 2 and improves the vibration resistance. Thereby, the vibration of the disc-type hologram recording medium 4 can be suppressed, and the fluctuation of the interference fringes of the recording signal generated by this vibration can be reduced.

  Further, since the cartridge opening 5 is formed by opening the outer edge of the cartridge opening 5, the shape of the cartridge, which is a housing for housing the disk-type hologram recording medium, is simplified, and the cartridge-containing hologram The formation cost of the recording medium can be reduced.

  The shutter 3 is configured to cover the cartridge opening 5 so as to be slidable along the outer edge of the cartridge 2 and to close the cartridge opening 5. The shutter 3 includes a shutter opening 6 that can expose the entire cartridge opening 5 to the outside. The shutter 3 is slid so that the shutter opening 6 exposes the entire cartridge opening 5 to the outside. By doing so, the cartridge opening 5 is opened.

  Therefore, the configuration of the shutter 3 can be simplified, and the opening and closing of the cartridge opening 5 of the cartridge storage hologram recording medium 1 can be smoothly performed.

  Further, according to the recording / reproducing apparatus 10 described above, the trajectory at the time of writing the optical axes of the reference light RL and the signal light SL, which are projection lights used for writing on the cartridge-holding hologram recording medium 1. However, the recording / reproducing apparatus 10 is formed so as to coincide with the radial direction of the cartridge-containing hologram recording medium 1.

  For this reason, the recording / reproducing apparatus 10 smoothly performs writing and reading on the disc type hologram recording medium 4 having the cartridge opening 5 formed along the radial direction of the disc type hologram recording medium 4. be able to.

  In addition, the reference light RL, which is one of the projection lights used for writing to the cartridge storage hologram recording medium 1, has an optical axis of the reference light RL on the outer peripheral side of the cartridge storage hologram recording medium 1. The recording / reproducing apparatus 10 is formed so as to irradiate the cartridge-containing holographic recording medium 1 so as to face the inner circumference side.

  Therefore, the conjugate mirror 29 used when reading the cartridge-housing hologram recording medium 1 can be arranged on the inner peripheral side of the cartridge-housing hologram recording medium 1. Therefore, the recording / reproducing apparatus 10 can be reduced in size.

  In the cartridge storage type hologram recording medium 1 in the above embodiment, as described above, the conjugate mirror 29 is arranged on the inner peripheral side of the disc type hologram recording medium 4 as shown in FIGS. However, it may be arranged on the outer peripheral side of the disc-type hologram recording medium 4.

  Further, in the cartridge storage type hologram recording medium 1 in the above embodiment, the following measures may be taken for the cartridge 2. FIG. 16 is a perspective view of the cartridge 2A to which this countermeasure is applied, and FIG. 17 is an enlarged perspective view of the vicinity of the cartridge opening 5A in a state where the shutter 3 is opened in the cartridge storage type hologram recording medium 1A to which this countermeasure is applied. It is.

  16 and 17, the cartridge housing type hologram recording medium 1A includes a cartridge bridging bridge (on the outer edge of the cartridge 2A of the cartridge housing type hologram recording medium 1A, which closes the cartridge opening 5A along the outer edge). The above-described casing bridging beam 5b is formed.

  This cartridge bridging bar 5b is used to project the reference light RL, the reference light CRL, and the signal light SL onto the disk hologram recording medium 4 built in the cartridge storage hologram recording medium 1, and from the disk hologram recording medium 4. Is formed at the outer edge of the cartridge 2A so as not to prevent the reproduction light CL from being emitted.

  With this cartridge bridging bar 5b, the rigidity of the cartridge 2A is improved, and the entire thickness of the cartridge 21 can be reduced. Moreover, vibration resistance can be improved. Thereby, the vibration of the disc-type hologram recording medium 1A can be suppressed, and the fluctuation of the interference fringes of the recording signal generated by this vibration can be reduced.

  Further, in the cartridge storage hologram recording medium 1 in the above embodiment, the following countermeasure may be taken for the shutter 3. FIG. 18 is a perspective view of the shutter 3A to which this countermeasure has been applied, and FIG. 19 is an enlarged perspective view of the vicinity of the cartridge opening 5 in a state where the shutter 3A is opened in the cartridge storage type hologram recording medium 1B to which this countermeasure has been applied. It is.

  18 and 19, the cartridge storage hologram recording medium 1B includes a shutter bridge that closes the shutter opening 6A along the outer edge of the shutter opening 6A of the cartridge storage hologram recording medium 1B. A crosspiece 6b is formed.

  The shutter bridge 6b projects the reference light RL, the reference light CRL, and the signal light SL to the disk-type hologram recording medium 4 built in the cartridge-containing hologram recording medium 1 in the same manner as the cartridge bridge 5b described above. In addition, it is formed at the outer edge of the shutter 3B so as not to prevent the reproduction light CL from being emitted from the disc-type hologram recording medium 4.

  By this shutter bridge 6b, the rigidity of the shutter 3A is improved and the vibration resistance can be improved. Thereby, the vibration of the disc-type hologram recording medium 1B can be suppressed, and the fluctuation of the interference fringes of the recording signal generated by this vibration can be reduced. Further, the thickness of the entire cartridge 2 can be reduced.

  The countermeasures applied to the cartridge 2A and the countermeasures applied to the shutter 3A may be reflected together on the cartridge-containing hologram recording medium 1 in the present embodiment. .

DESCRIPTION OF SYMBOLS 1 Cartridge storage type hologram recording medium 1A Cartridge storage type hologram recording medium 1B Cartridge storage type hologram recording medium 2 Cartridge 2A Cartridge 3 Shutter 3A Shutter 4 Disc type hologram recording medium 4a Transparent substrate 4b Transparent substrate 4c Recording medium 4d Hub 5 Cartridge opening 5A Cartridge opening 5a Cartridge circular opening surface 5b Cartridge bridging beam 6 Shutter opening 6A Shutter opening 6a Shutter circular opening surface 6b Shutter bridging beam 10 Recording / reproducing apparatus 11 Optical system mechanism 20 Laser light source 21 Collimator unit 22 Recording shutter 23 Beam separation unit 24 Deflection mirror 25 Relay lens 26 Polarization beam splitter (PBS)
27 Aperture 28 Objective Lens 29 Conjugate Mirror 29a 1/4 Wave Plate 30 Image Sensor 31 Reflective Liquid Crystal Spatial Modulator 41 Carriage 41a Fork End 41b Recess 42 Rotation Drive Mechanism RL Reference Light SL Signal Light CR L Reference Light CL Reconstructed Light

Claims (10)

A disk-shaped disc-type hologram recording medium;
A housing that is rotatably housed inside the disk-type hologram recording medium, and is shielded so that external light does not enter the interior;
A housing opening provided in the housing so that projection light can enter or exit on the front and back surfaces of the disc-type hologram recording medium,
A shutter that opens the housing opening when writing or reading the disk-type hologram recording medium using the projection light, and closes the housing opening at other times. A cartridge-containing holographic recording medium characterized by the above. The cartridge-containing holographic recording medium according to claim 1,
The housing opening is a cartridge storage hologram recording medium formed along a radial direction of the disc hologram recording medium. The cartridge-housing hologram recording medium according to claim 1 or 2,
The housing opening is a cartridge-containing holographic recording medium formed so that the projection light can reach the outer peripheral edge of the disc holographic recording medium. In the cartridge accommodation type hologram recording medium according to any one of claims 1 to 3,
The housing opening is a cartridge-containing holographic recording medium formed by opening an outer edge of the housing opening. In the cartridge accommodation type hologram recording medium according to any one of claims 1 to 3,
A cartridge-containing holographic recording medium in which a casing bridging bar that closes the casing opening along the outer edge is formed at an outer edge of the casing. In the cartridge accommodation type hologram recording medium according to any one of claims 1 to 5,
The shutter is
Covering the housing opening slidably along the outer edge of the housing and closing the housing opening;
The housing opening is provided with a shutter opening capable of exposing the entire housing opening to the outside, and the shutter opening is slid so that the shutter opening exposes the entire housing opening to the outside. Cartridge-type holographic recording medium that opens the part. The cartridge-containing holographic recording medium according to claim 6,
The cartridge opening-type hologram recording medium, wherein the shutter opening is formed by opening an outer edge of the shutter opening. The cartridge-containing holographic recording medium according to claim 6,
A cartridge-containing holographic recording medium in which a shutter bridge bar that closes the shutter opening along the outer edge is formed at an outer edge of the shutter. A recording / reproducing apparatus for a cartridge-housing hologram recording medium, wherein the cartridge-housing hologram recording medium according to any one of claims 1 to 8 is written or read using the projection light.
The trajectory at the time of writing of the optical axes of the reference light and the signal light, which are the projection light used for writing to the cartridge-housing hologram recording medium, is a disk of the cartridge-housing hologram recording medium. A recording / reproducing apparatus for a cartridge-containing hologram recording medium that matches the radial direction of the hologram recording medium. A recording / reproducing apparatus for a cartridge-housing hologram recording medium, wherein the cartridge-housing hologram recording medium according to any one of claims 1 to 8 is written or read using the projection light.
The reference light, which is one of the projection lights used for writing on the cartridge-housing hologram recording medium, has an optical axis of the reference light from the outer circumference side of the cartridge-housing hologram recording medium to the inner circumference. A recording / reproducing apparatus for a cartridge-containing holographic recording medium that irradiates the cartridge-containing holographic recording medium so as to face the cartridge.

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