HOLOGRAPHIC MEMORY

SEMINAR ON HOLOGRAPHIC MEMORY : As processors and buses, almost double its data capacity every three years (Moore's Law), data storage has struggling to bridge the gap. CPU can execute a run every nanosecond, which is six orders of magnitude faster than a single disk access. Much research has gone in finding hardware and software solutions for closing time gap between processors and data storage. Some of these advances include cache, pipeline, optimizing compilers, and RAM. As IT is evolving, as are applications that use computers for. Recently, large binary files that contain audio or image data have become commonplace, increasing need for high capacity data storage and access. A new form of high capacity data retention should be developed to cope with such large files quickly and efficiently. holographic memory is a promising technology for data storage because it is a true three-dimensional storage system, data can access an entire page at once rather than sequentially, and there are very few moving parts limitations of the mechanical movements are minimized. holographic memory using a photosensitive material to absorb types of interference reference beam and signal beam coherent light, which reflects the signal beam of an object it contains data in the form of light and dark areas. Nature the photosensitive material is such that the registration interference pattern can be replicated using a beam of light material, which is identical to the reference beam. The resulting light, which will be sent by means the interference pattern is recorded and collected in a laser detector array that covers the entire surface holographic media. Many holograms can be recorded In the same state by changing the angle or wavelength the incident light. A full page of data is available in this way.
The three characteristics that make holographic memory an interesting candidate to replace magnetic storage devices stored data redundancy, parallelism, and multiplexing. Stored The data was rejected due to the nature of the interference pattern between the reference and signal beams are printed on holographic medium. Since the interference pattern is a plane wavefront is propagated in the stored pattern volume holographic medium, repeated at regular intervals. The Data can be destroyed at a certain level before the information is lost making it a very secure data storage. In addition, the effect of lost data is not the signal to noise ratio, so that the number of data that can be safely lost depends on the desired signal noise. stored holograms is massively parallel because data is recorded as an optical wave front is recovered page in a single access. When light is used to retrieve data and With no moving parts in the sensor array, the access time to data the order of 10 ms and a data transfer rate approaches 1.0 GB / sec. Multiplexing allows many different models to be stored in the same volume of glass by simply changing the angle at which The record reference beam hologram.