Abstract: Techniques are provided for increasing spectral efficiency over data channels in a storage or communication system. In some embodiments, data may be encoded and transmitted over multiple channels. The transmitted data from the multiple channels may be considered together as a channel bundle, thereby increasing the edge transitions of the group of signals to improve clock recovery and reduce coding constraints. In some embodiments, the channel bit size is reduced to maximize data rates based on the reduced coding constraints. Furthermore, the channel bundle has only one channel with timing markers, so that a receiver may receive information from the channel bundle and recover clocking based on the timing markers in the one channel.

Abstract: In an optical information recording device and optical information recording method for angularly multiplexing and recording data on pages on the same recording region on a hologram disk, data on each page is sequentially generated by sequentially dividing input data in predetermined units, the pages to be recorded on the same recording region are divided into page groups so that pages to be recorded adjacently by the angular multiplexing may not belong to the same group, each page group is individually subjected to inter-page coding processing for computing an error-correcting code and adding the computed error-correcting code, and data on the pages subjected to the inter-page coding processing is angularly multiplexed and recorded on the hologram disk.

Abstract: When books are densely bedded on a recording medium for recording a hologram on the medium with a high density, the books need to be positioned at a reference light irradiation position with a high precision when reproducing.

Abstract: Disclosed is an optical information recording and reproducing device capable of recording an interference fringe pattern as a hologram in an optical information recording medium, the interference fringe pattern being formed by a signal beam superimposed with signal information and a reference beam, and also capable of reproducing the signal information from the optical information recording medium, the device having a light source unit to emit light, a light splitting unit to split the light into the reference beam and the signal beam, a spatial light modulation unit to superimpose the signal information on the signal light, and a light detection unit to detect an image reproduced by the reference beam, wherein information about defects on the spatial light modulation unit is recorded in the optical information recording medium.

Abstract: The above-described problem can be solved by the following optical-information reproducing apparatus: An optical-information reproducing apparatus for reproducing a hologram storage medium into which an interference pattern is recorded as a hologram, the interference pattern being formed by causing a reference beam and a signal beam to interfere with each other, the optical-information reproducing apparatus, including an optical detector for detecting a reproduced beam, the reproduced beam being acquired by illuminating the recorded hologram with the reference beam, an optical element for generating a first reference beam and a second reference beam by branching the reference beam, a wavefront detector for detecting wavefront aberration of the reference beam by causing the first reference beam and the second reference beam to interfere with each other, and a wavefront compensator for compensating the wavefront of the reference beam, wherein the wavefront compensator is adjusted based on an output of the wavef

Abstract: An optical information recording apparatus configured to record information into an information recording medium by using holography, the apparatus including: a signal generation unit configured to generate two-dimensional data; and a two-dimensional spatial light modulator unit configured to display the two-dimensional data and to spatially modulate a transmitted or reflected beam, wherein the two-dimensional spatial light modulator unit includes a signal region and an external region, the signal region displays two-dimensional data based on user data, the external region displays two-dimensional data not including the user data, and the signal generation unit generates two-dimensional data in such a manner that a frequency of the two-dimensional data displayed on the external region becomes equal to or larger than a frequency of the two-dimensional data displayed on the signal region.

Abstract: An optical information reproducing device includes: a light source that emits light to the optical information recording medium; a light source control unit that controls a wavelength of the light emitted from the light source; a reference beam angle control unit that controls an incidence angle of the reference beam to the optical information recording medium; a light detector that detects a reproduction image from the optical information recording medium or a brightness distribution of the reproduction image; a reproduction image processing unit that detects a bright line of the reproduction image on the basis of a detection result of the light detector and outputs a detection result of the bright line; and a controller that controls the wavelength of the light emitted from the light source, on the basis of an output of the reproduction image processing unit, and controls the incidence angle of the reference beam.

Abstract: An information storage device has small compartments for storing information in a solid body and can be used as a memory medium. The solid body can have at least one pair of parallel planar portions on its surface. The information is divided into bits and stored in discrete minute areas that are distributed three-dimensionally inside the memory medium. The data can be converted into a digital format for storage to regulate the number of ‘1s’ recorded in a direction of the memory medium.

Abstract: A component comprising a stacked interleaved film structure that includes a plurality of layers inert to light. Alternating layers are either doped with a reverse saturable absorber (RSA) material or the RSA material is located between the adjacent inert layers. In some embodiments, the inert alternating layers have different refractive indices. A data storage device and methods of manufacture are also disclosed.

Abstract: Provided is an information encoding method and a holographic memory device which increase the amount of information per page of a holographic memory and reduce the bit error rate to ensure a larger multiplexing number. The holographic memory information encoding method expresses information of signal page data in a holographic memory as a multi-stage data using different resolution by block coding, and superimposes each data on a single page of signal page data. The multi-stage data using different resolution is realized by light amplitude data and phase data. The amplitude data is divided by area through block coding. When n odd-numbered ON bits exist in a divided area of the phase data, a phase of 2?s/n (where n and s are natural numbers) is imparted as s-th phase information to one value of binary data, and the same phase is imparted to the other value of binary data.

Abstract: This invention relates a method of six-dimensional optical multilayer storage using two-photon absorption writing, erasing and optical coherence tomography reading and the apparatus designed based on this method. The invented system stores data in three spatial dimensions plus three physical dimensions of wavelength, intensity and polarization. It has large storage capacity of over 32 Tbytes per DVD sized disk and ultrafast reading speed of over 25 Gbits/s with high signal-to-noise ratio of over 76 dB. The larger capacity of over 1 Pbyte per disk is potential. Furthermore, the invented system has relatively simple optical structure, easy light manipulation for addressing the storage cell and high compatibility with the CDs and DVDs. It is an actually practicable optical large capacity storage technology.

Abstract: A data recording apparatus and method using three dimensional (3D) optical memory and an authentication apparatus and method using 3D optical memory are provided. The data recording apparatus includes a recording excitation light splitting unit, a condition storage unit, and a data recording unit. The recording excitation light splitting unit splits recording excitation light into first split light and second split light. The condition storage unit stores recording conditions including information about the waveforms, wavelengths and phases of the split light and information about an arrangement of reflection mirrors configured to reflect the split light. The data recording unit records storage data by making the split light incident on the 3D optical memory through the reflection mirrors under the recording conditions.

Abstract: An optical system capable of obtaining a high-resolution image using interference and thus capable of providing a stable signal is realized. A particular polarization state of response light emitted from an object is selected, and light in the selected particular polarization state is split into two beams. The split two beams are polarized into two different polarization states. After one of the two beams is subjected to an image inversion, the two beams are condensed such that they interfere with each other. The interfering light is split into a plurality of beams, and each of these beams is detected after they are passed through different polarizing filters. Detected signals are combined together and processed to obtain high-stability amplitude information without being influenced by a phase difference between the two beams.

Abstract: The present invention provides a technology which estimates the most suitable cure time which changes with the environment when recording a hologram and adjusts the cure time in real time, thereby enabling a suitable pre-cure or post-cure. When irradiating an optical information recording medium with cure light, the light transmitted from the optical information recording medium is detected by a detector and the irradiation time is adjusted by continuing irradiation until the intensity of the transmitted light detected exceeds a prescribed reference value.

Abstract: A method of calculating a reliability effective in a decoding process of hologram. An optical information reproducing apparatus that reproduces information with the use of the holography includes an image acquisition unit that reproduces two-dimensional data from a hologram disc, an image equalization unit that makes the two-dimensional data equal to target data having a target PR characteristic, a soft output decoding unit that decodes output data of the image equalization unit on the basis of the PR characteristic, and outputs a decoded result having a reliability, and an error correction unit that conducts an error correction of the data on the basis of the decoded result.

Abstract: A holographic optical pickup device includes an optical axis split element for splitting a reference beam into two light beams in different propagation directions having polarized states substantially orthogonal to each other, angular variable elements for changing incident angle of the reference beam for irradiating an optical information recording medium, an image sensor for detecting a diffracted beam generated from a recorded region upon irradiation of the optical information recording medium with the reference beam to form a reproduction signal, and photodetectors for detecting the diffracted beam generated from the recorded region upon irradiation of the optical information recording medium with the reference beam. An angular error signal is generated for controlling the angular variable element using signals detected by the photodetectors.

Abstract: In reproduction of a two-dimensional page data from an optical information recording medium utilizing holography, a reproduced two-dimensional page data is divided into a plurality of areas each of which has a predetermined size, the divided two-dimensional areas are individually subjected to adaptive equalizing, and then are coupled to restore the condition of the original two-dimensional page data.

Abstract: The present invention provides a recording medium reproducing method comprising the steps of: irradiating light onto a recording medium, the recording medium including a data image and a reference pattern, the reference pattern being divided by a plurality of fractional regions, the fractional regions being in invert, rotational and symmetrical relationship; determining information associated to data-image distortion based on the reference pattern; and correcting position of the data image based on the information relating to data-image distortion.

Abstract: The present techniques present methods and systems for increasing a data reading rate on optical data disks using a single reading head. The methods take advantage of the difference between a mean focal distance (MFD), or minimum spacing that the detector can distinguish between bits, and the minimum separation of bits in a single track to increase the reading speed. As the bits may be more closely spaced across adjacent tracks or layers, these techniques may be used to increase the reading speed of the disk. Specifically, the data symbols that make up a single bit-stream may be stored in a pattern horizontally across adjacent tracks, or vertically across adjacent layers. Accordingly, the focal point of the detector is scanned across the disk in the same pattern to read the individual data symbols.

Abstract: The invention combines several techniques applying high-resolution photosensitive emulsions for the long-term, archival storage of data, images and text. Data is stored as vertical interference patterns of multiple frequencies in a photographic emulsion. Read-out of the stored data uses a precision mechanism to locate and decode stored data.

Abstract: A data recording apparatus and method using three dimensional (3D) optical memory and an authentication apparatus and method using 3D optical memory are provided. The data recording apparatus includes a recording excitation light splitting unit, a condition storage unit, and a data recording unit. The recording excitation light splitting unit splits recording excitation light into first split light and second split light. The condition storage unit stores recording conditions including information about the waveforms, wavelengths and phases of the split light and information about an arrangement of reflection mirrors configured to reflect the split light. The data recording unit records storage data by making the split light incident on the 3D optical memory through the reflection mirrors under the recording conditions.

Abstract: There is disclosed an optical information recording/reproducing apparatus for optically recording and/or reproducing information in and from an optical recording medium. The apparatus has an oscillator light generator for generating oscillator light that is made to overlap and interfere with reproduced light from the optical recording medium, an oscillator light modulator for producing a given phase difference between the oscillator light and the reproduced light, a light detector for detecting interference light in which the oscillator light and the reproduced light overlap each other, a wavefront deviation detector for detecting an amount of wavefront deviation between the oscillator light and the reproduced light from an output from the light detector, and a compensation amount calculation unit for calculating a wavefront compensation amount from the amount of wavefront deviation. The phase difference produced by the oscillator light modulator is controlled based on the wavefront compensation amount.

Abstract: An optical information recording/reproducing apparatus for recording an interference pattern between signal light and reference light information-multiplexed as a hologram in an optical information recording medium and for reproducing information recorded in the optical information recording medium on the basis of the recorded hologram with use of the reference light. The apparatus includes a light source for emitting light and a coherency controller for controlling a coherency of the light source. The apparatus controls the coherency controller in such a manner as to switch between a coherency required in a recording mode and a coherency required in a reproducing mode.

Abstract: An optical information recording/reproducing apparatus for recording information on a recording medium and/or reproducing information from the recording medium, includes: a laser light source for performing recording and/or reproducing information; a shielding part, using a liquid crystal, that can switch between transmission and interception of laser light emitted from the laser light source; a driving circuit for driving the switching between transmission and interception of the shielding part; a moving part for relatively moving the shielding part and the laser light; and a controlling circuit for controlling the moving part. The moving part relatively moves the shielding part and the laser light so as to switch a region to which the laser light is applied from a first region of the shielding part to a second region thereof different from the first region, in order to prevent the liquid crystal from deteriorating.

Abstract: A recording signal beam and a recording reference beam are irradiated onto a first surface of a holographic recording medium to write an information as an interference pattern therein. Next, a reflective layer is provided on a second surface opposite to the first surface of the holographic recording medium such that the reflective layer is adhered with the second surface, and a reproducing reference beam is irradiated onto the first surface of the holographic recording medium so as to read a signal beam which is reflected at the reflective layer and reproduced from the holographic recording medium.

Abstract: A holographic optical pickup device includes an image sensor that detects a diffracted beam generated from the region to be reproduced when irradiating an optical information recording medium with a reference beam, and sets the detected diffraction beam as a reproduction signal, and a photodetector that is different from the image sensor, which detects the diffracted beam generated from a recorded region in the recording medium when irradiating the recording medium with the reference beam. A light receiver of the photodetector is divided into a plurality of light receiving planes so as to generate the position error signal indicating the positional shifting of the region to be recorded/reproduced of the recording medium with respect to the objective lens from a differential signal of a plurality of signals derived from the respective light receiving planes.

Abstract: An optical information recording/reproduction device includes a detection unit which detects a focus-direction height of a recording medium, a focus adjustment unit which adjusts a focus-direction distance between the recording medium and a signal light optical system and a reference light system, and a control unit which controls the focus adjustment unit so that a relative distance between the object lens of the signal light optical system and the recording medium is adjusted according to the focus-direction height of the recording medium detected by the detection unit.

Abstract: An optical information recording/reproducing apparatus and an optical information recording/reproducing method that record information using holography, wherein the optical information recording/reproducing apparatus includes a signal generation unit that generates two-dimensional data by a two-dimensional encoding method in which a lower-limit value of a number of continuous ON/OFF pixels in an array in one direction of pixels in a two-dimensional spatial light modulator is K(K?2, K: natural number); and a pickup that records the two-dimensional data, generated by the signal generation unit, on a hologram disc.

Abstract: The present invention relates to a reproduction device of a holographic memory capable of precisely reproducing multi-value phase information without being influenced by noise. This holographic memory reproduction device comprises: a hologram diffraction ray generation unit which irradiates a first reference ray to the holographic memory and generates a diffraction ray of the first hologram; a hologram generation unit which changes the phase of a second reference ray which may interfere with the diffraction ray of the first hologram and generates a second hologram from the diffraction ray of the first hologram and the second reference ray to which the phase has been changed; a detection unit which detects the intensity distribution of the second hologram; and a processing unit which demodulates the phase modulation signal or the space quadrature amplitude modulation signal on the basis of the intensity distribution.

Abstract: An optical information recording/reproducing apparatus, to apply holograms of an angle multiplex recording method therein includes: a light source to emit a light beam; a divider unit to divide the light beam into a signal beam and a reference light; an angle variable unit to change an angle of the reference light incident upon an optical information recording medium; a spatial light modulator unit to add information to the signal beam; an objective lens to irradiate the signal beam on the medium; an image pickup unit to detect a diffracted light generating from a recording region, when the reference light is irradiated on the medium; and an optical element to shape a form of light flux of the reference light, so that a light flux diameter of the reference light in a multiplex direction becomes larger than the light flux diameter of the reference light in a pitch direction.

Abstract: A holographic memory apparatus includes an optical detector which receives reflected light of reference beam from the surface of a hologram recording medium. An incident angle of the reference beam is estimated on the basis of information on a focused position on the optical detector. When the incident angle is different from a target incident angle, the incident angle of the reference beam is adjusted according to a difference between the incident angle and the target incident angle.

Abstract: A computer implemented method to display an industrial installation, which display may also display information about an event or an alarm in the installation. The method includes displaying an image which appears to the viewer to be a three dimensional holographic image including a view of the industrial installation. The image may also include one or more points in three dimensional space and which point or points are each mapped to a corresponding point or position in the industrial installation. A pointing device for actively indicating position on the image reflecting objects or positions in the installation is also described.

Abstract: An apparatus and a method for reading from and/or writing to holographic storage media using a coaxial arrangement of an object beam and one or more reference beams or a coaxial arrangement of a reconstructed object beam and one or more reference beams is proposed. A focus of the one or more reference beams within a holographic storage medium is shifted along the optical axis relative to a focus of the object beam or the reconstructed object beam.

Abstract: A method of calculating a reliability effective in a decoding process of hologram. An optical information reproducing apparatus that reproduces information with the use of the holography includes an image acquisition unit that reproduces two-dimensional data from a hologram disc, an image equalization unit that makes the two-dimensional data equal to target data having a target PR characteristic, a soft output decoding unit that decodes output data of the image equalization unit on the basis of the PR characteristic, and outputs a decoded result having a reliability, and an error correction unit that conducts an error correction of the data on the basis of the decoded result.

Abstract: An optical information recording/reproducing apparatus and an optical information recording/reproducing method that record information using holography, wherein the optical information recording/reproducing apparatus includes a signal generation unit that generates two-dimensional data by a two-dimensional encoding method in which a lower-limit value of a number of continuous ON/OFF pixels in an array in one direction of pixels in a two-dimensional spatial light modulator is K(K?2, K: natural number); and a pickup that records the two-dimensional data, generated by the signal generation unit, on a hologram disc.

Abstract: The present invention provides a technology which estimates the most suitable cure time which changes with the environment when recording a hologram and adjusts the cure time in real time, thereby enabling a suitable pre-cure or post-cure. When irradiating an optical information recording medium with cure light, the light transmitted from the optical information recording medium is detected by a detector and the irradiation time is adjusted by continuing irradiation until the intensity of the transmitted light detected exceeds a prescribed reference value.

Abstract: An optical pickup device includes a galvanometer mirror that changes an incident angle of a reference beam to an optical information recording medium, an image sensor that detects a diffracted beam from a region to be reproduced upon irradiation of the recording medium with the reference beam, and sets the detected diffracted beam to a reproduction signal, and a photodetector that detects the diffracted beam generated from a plurality of recorded regions upon irradiation of the recording medium with the reference beam. The photodetector includes a plurality of light receivers, and generates an angular error signal indicating positional shifting of the incident angle of the reference beam from a differential signal of a plurality of signals derived from the respective light receivers so as to control the angle of the galvanometer mirror.

Abstract: An optical tape pick up unit includes a holographic optical element and an aspheric objective lens. The holographic optical element splits a laser beam into first order beams and introduces pre-compensating wavefront error into the first order beams. The aspheric objective lens focuses the first order beams onto optical tape and introduces wavefront error into the first order beams having a magnitude similar to and polarity opposite that of the pre-compensating wavefront error.

Abstract: A test element is disclosed for analyzing a human or animal body fluid sample. The test element includes a substrate carrying a test field with a reagent for effecting a detection reaction when exposed to the body fluid sample, and an optical data storage in which data regarding the test element, preferably calibration data, is stored. Accordingly, the data storage is a holographic data storage. A hologram reader also is disclosed for reading the data storage of such a test element. Moreover, a hologram label and a method for manufacturing a hologram label are disclosed, as is a medical product including a holographic data storage in which data regarding the product is stored.

Abstract: Multi-level recording is quite effective for attaining a larger capacity and a higher transfer rate in the case of an optical disk; however, with conventional technologies, a SIGNAL-TO-NOISE RATIO of a signal deteriorates along with an increase in a multi-level degree, creating a factor for limitations to the multi-level degree. In order to solve problems, when optical information is recorded by use of a standing wave occurring due to interference between two light beams, at least one of the two light beams is modulated in multi-stages. Further, at the time of regeneration, a regeneration reference beam is caused to interfere with respective polarization components of a regeneration beam, the polarization components being orthogonal to each other, thereby concurrently generating not less than three interference beams differing in interference phase from each other before being detected.

Abstract: An encoding device for converting m-bit data words into n-bit (both n and m are integers and 2n?2m×2) code words includes a first encoding table in which 2m code words selected from the 2n n-bit code words correspond to 2m m-bit data words, a second encoding table in which 2m code words, which do not overlap with the code words in the first encoding table, of the 2n n-bit code words correspond to 2m m-bit data words, and an encoding unit which selects and outputs a code word, in which an absolute value of a code string DSV is smaller, from code words corresponding to the input m-bit data words in the first encoding table and code words corresponding to the input m-bit data words in the second encoding table.

Abstract: Provided is an information encoding method and a holographic memory device which increase the amount of information per page of a holographic memory and reduce the bit error rate to ensure a larger multiplexing number. The holographic memory information encoding method expresses information of signal page data in a holographic memory as a multi-stage data using different resolution by block coding, and superimposes each data on a single page of signal page data. The multi-stage data using different resolution is realized by light amplitude data and phase data. The amplitude data is divided by area through block coding. When n odd-numbered ON bits exist in a divided area of the phase data, a phase of 2?s/n (where n and s are natural numbers) is imparted as s-th phase information to one value of binary data, and the same phase is imparted to the other value of binary data.

Abstract: An optical-information reproducing apparatus for reproducing information from an optical-information storage medium where an interference pattern between a signal beam and a reference beam is recorded as page data by being angle-multiplexed, the optical-information reproducing apparatus, including a light-source for emitting a light beam, an optical element for splitting the light beam into the reference beam and the signal beam, an angle-controlling element for controlling the reference beam into a direction which is perpendicular to the angle-multiplexed direction, the reference beam being guided to enter the optical-information storage medium, an optical detector for detecting a reproduced image which is reproduced by the reference beam, and a position-controlling circuit for controlling position relationship between the reference beam and the optical-information storage medium.

Abstract: A holographic recording medium in which information can be reproduced by phase conjugate beam without requiring a mirror for obtaining the phase conjugate beam and its driving part and recording density is not reduced. The recording medium includes a recording layer in which an interference pattern is recorded and a light absorption/transmission layer which can be reversibly changed to be in a first state where signal beam and reference beam passed through the recording layer are absorbed at the time of recording of information and a second state where the reference beam is transmitted at the time of reproduction of information, and the reference beam transmitted through the light absorption/transmission layer is reflected by a reflection layer to produce the phase conjugate beam.

Abstract: An optical disk playback device comprises one or more lasers, an optical assembly, an optical detector, and controller circuitry coupled to the optical detector. The optical assembly is configured to direct incident light from the one or more lasers so as to form first and second scanning spots on a surface of an optical disk, and is further configured to direct corresponding reflected light from the first and second scanning spots on the surface of the optical disk to the optical detector. The optical detector is configured to process the reflected light from the first and second scanning spots to generate respective first and second data streams, and the controller circuitry is configured to generate a three-dimensional image signal from the first and second data streams.

Abstract: In a system of detecting an interference light with a light not irradiated onto an optical disc to increase the S/N ratio, it is difficult to stably acquire a reproduced signal with a simple configuration. Since the recording density is not improved, an improvement in transfer rate is difficult. In an optical information recording/reproducing apparatus where two optical beams face each other and are focused at the same place of a recording medium to record a standing wave developed by interference of the two optical beams, a phase difference of the two optical beams is modulated in a multiple stage and recorded. During reproduction, an interference light of a reproduced light from the recording medium and another reproduction reference light is detected as a reproduced signal, and a phase servo control stabilizing the phase of interference during reproduction by using a low frequency component of the reproduced signal is conducted.

Abstract: The invention provides a hologram generating device and a hologram generating method that allows the generation of a hologram for reproducing an easily observable three-dimensional image without restrictions on object sizes. The hologram generating device includes an object light generation means, a reference light generation means, an irradiation means, a polarization light selecting reflection means, and a polarization conversion means, wherein the one of the object light and the reference light incident from the rear surface is made to interfere with the other of the object light and reference light incident from the front surface in the hologram recording layer to record a reflection type hologram on the hologram recording layer.

Abstract: A holographic memory apparatus includes an optical detector which receives reflected light of reference beam from the surface of a hologram recording medium. An incident angle of the reference beam is estimated on the basis of information on a focused position on the optical detector. When the incident angle is different from a target incident angle, the incident angle of the reference beam is adjusted according to a difference between the incident angle and the target incident angle.

Abstract: An optical information reproducing apparatus and an optical information reproducing method using the same are provided. The optical information reproducing apparatus includes: a reference beam providing unit which inputs a reference beam to a reproduction recording area to be reproduced and a peripheral recording area around the reproduction recording area on an optical information recording medium, a peripheral beam detecting unit which transmits a reproduction beam reproduced from the reproduction recording area in response to the reference beam and detects a peripheral beam reproduced from the peripheral recording area, a tracking servo unit which analyzes optical information of the detected peripheral beam and controls a tracking position, and a reproduction beam detecting unit which detects the reproduction beam having pass through the peripheral beam detecting unit.

Abstract: According to one embodiment, a data reproducing apparatus includes a data recording medium, light source unit, light application unit, photodetector unit and control unit. An address mark string including address marks is formed on the data recording medium. The address marks are spaced from each other by a distance depending on address data. The light application unit is configured to split the light beam into a first branch light beam and a second branch light beam and apply the first and second branch light beams to the address mark string at different angles. The photodetector unit is configured to detect first reflected light beams and second reflected light beams from the address mark string to generate image data. The first and second reflected light beams result from the first and second branch light beams, respectively. The control unit is configured to reproduce address data based on the image data.