<title>Large-scale volume holographic storage in the long interaction length architecture</title>

Abstract

We (lescribe a page-formatted random-access holographic memory designe(l to store up to 160,000 holograms. The memory consists of 16 vertically spaced locations, each containing 10,000 holograms, which in turn are organized as 10 fractal-multiplexed rows of 1000 angularly-multiplexed holograms. A segmented mirror array is used to enable random access to any of the stored holograms within the access time of a non-mechanical angle scanner such as an acousto-oJ)tic deflector. Using a mechanical scanner with such a mirror array, we demonstrate storage of 10,000 holograms at a single location of the system, as well as simultaneous storage and recall of holograms at 6 locations, including the highest and lowest of the 16 locations.

The Optical Memory–Electric Computer Interface as a Parallel Processing Architecture

“…We defined the readout data rate earlier as R = mn=T r (3) In fact, this equation needs to be scaled by a factor r to account for the redundancy introduced by the data code employed in the system, (i.e., r is the code rate). For example, if we use standard 8-bit ASCII code mapped on 15 bits then r = 8=15.…”

“…Since the 1970s several optical storage systems have been proposed and demonstrated. Volume holographic storage [3], two-photon threedimensional memory [4], and spectral hole-burning memory appear to be the most promising technologies. In addition, optical and magneto-optical disks became popular consumer electronic products and in 1995 nearly every personal computer is equipped with a compact disk read-only memory (CD-ROM) unit [5].…”

Near-optimal parallel distributed data detection for page-oriented optical memories

“…Based on these observations, we suggest a metric-based GL propagation rule analogous to (8)- (9) (12) (13) where is the metric version of in logdomain. After iterations are accomplished, the decisions are made according to: if otherwise…”

<title>Volume holographic wavelet correlators with multi-input channels</title>

“…13 With the development of some key elements such as crystal, space light modulator (SLM) and photoelectric detector array, 1 0,000 images have been recorded and restored in a single crystal. 4 The main attractive characteristic of the technique is its inherent parallel processing, which offers a suitable mechanism for pattern recognition.57 Once all the patterns are stored in a photorefractive crystal, it can be employed as a database for pattern recognition or other processing. An input image can be compared with all the stored patterns simultaneously to achieve high speed and efficiency.…”

“…H + Fm S H2 Rmm + F, Sm 2 R;,m(4) An inverse Fourier transform is needed to obtain the correlation outputs. Seeing about the third part in the above function, which satisfies the Bragg condition, we will get cci(f7 ®h)®(Sm ® m(5) Compare with the function (1), a wavelet auto-correlation peak will appear along the reference beam Rm ,k if the input imageJ is most similar to one of the pattems Sm Reference beam(a) (b) yc yc Fig.…”