Abstract: A recording medium, a recording apparatus, and a recording method. Recording data is recorded as element holograms on a hologram recording medium, a synchronization signal selected from among a plurality of synchronization signals and recording data encoded for every predetermined unit amount are arrayed to facilitate reproduction.

Abstract: A reproduction apparatus is provided which reproduces, from a hologram recording medium on which digital data are recorded as an element hologram formed from interference fringes generated by interference of imaged data of the digital data as object light with reference light, the digital data. If a synchronization signal recorded in advance in a predetermined region of the hologram recording medium is detected successfully, then it is decided that the tracking state with regard to the element hologram is favorable. In this instance, signal processing is performed the image picked up from the element hologram to reproduce the digital data.

Abstract: Reproduction reference light is irradiated on a hologram recording medium on which imaged digital data are recorded as a plurality of element holograms in the form of interference fringes obtained by interference between object light of the digital data and recording reference light. Then, a reproduction image obtained from the hologram recording medium by the irradiation of the reproduction reference light is detected. Then, readout data are produced based on the detected reproduction image. Thereafter, it is discriminated whether or not the readout data should be stored into a memory, and the readout data are stored into the memory in response to a result of the discrimination. Where a predetermined amount or more of the data is accumulated in the memory, reproduction data are produced from the readout data accumulated in the memory and then reproduced.

Abstract: A reproduction apparatus is disclosed which reproduces, from a hologram recording medium on which digital data are recorded as an element hologram formed from interference fringes generated by interference of imaged data of the digital data as object light with reference light, the digital data. If a synchronization signal recorded in advance in a predetermined region of the hologram recording medium is detected successfully, then it is decided that the tracking state with regard to the element hologram is favorable. In this instance, signal processing is performed the image picked up from the element hologram to reproduce the digital data.

Abstract: A recording medium, a recording apparatus, and a recording method are disclosed. Where recording data are recorded as element holograms on a hologram recording medium, a synchronization signal selected from among a plurality of synchronization signals and recording data encoded for every predetermined unit amount are arrayed to facilitate reproduction.

Abstract: A hologram recording method and a hologram recording apparatus are provided. A hologram recording apparatus which forms information into element holograms for recording, includes: data page generating means for forming a two-dimensional matrix from a linear information sequence that is an encoding target and generate a data page; inner page encoding means for conducting encoding that is completed in the data page to generate an inner encoded page; interpage encoding means for conducting encoding over the inner encoded pages to generate an outer encoded page; and element hologram matrix generating means for forming the outer encoded page into a 2D code symbol, generating a physical page including the 2D code symbol, and continuously forming the physical page into element holograms to generate an element hologram matrix.

Abstract: In a digital signal reproducing apparatus various adjustment jobs and measurement jobs can be automatically executed by a simple operation by providing a clock generator, an external waveform equalizer, an error detector, an edge detection circuit, and a DC following circuit in addition to a waveform equalizer by which a reproduced analog signal waveform is processed and then converted to a digital signal. The digital signal is equalized by a digital filter and sampled and the digital signal and extracted clocks are supplied. The reproducing level and the equalizer coefficients can be automatically adjusted and an error rate can be automatically measured. A pulse width modulation or bias recording can be automatically determined and a recording current can be automatically adjusted by the system and the inclination of magnetic heads and the distance between the heads can also be automatically measured.