Holographic Memory

The wave of the future is here with the development of holographic memory storage. Though this new technology has been around for 30 years, it has only come to commercial use very recently when a company called InPhase brought the first reliable holographic storage to the market. It is believed that this new technology will surpass tape storage capacity by as soon as 2010.

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Description

The reason behind the holographic memory's power is its unique ability to hold more than one piece of information in a single location. While DVDs use a series of mirrors which each represent a single bit, a holographic disk holds a series of checkerboard-like patterns of information. These patterns change depending upon the angle which the disk is read. This process is similar to viewing a holographic image, where the visual appearance of an object will change when you look at it from different angles. A holographic disc has much more volume for holding information and data than a regular DVD could, because the bits are stored not just on the surface. Because of its small size and volumetric approach, the holographic storage actually has faster processing times, which saves time when searching for something. Objects are stored parallel, which makes it easier to search for data. Supposedly, a cubic centimeter can hold tens of terabits of information. All of the data is stored using the entire volume of the cylinders, with information overlapping in the same space. The designing of holographic storage actually requires a lot of physics, including waves and light.

A cool video can be seen here, where they describe more about holographic storage.



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How It Works

A laser's beam is split into two beams and they interact with each other in a crystal medium which produces a holographic image of the data.
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The object beam holds the information that is stored, and the reference beam was made so it can easily be reproduced. When they combine, there is a physical and chemical change in the photosensitive medium, of which a duplicate of is stored and saved. If one were to shoot a reference beam to the replica of the new beam, then the object beam would appear, and the other way around as well. To retrieve the data, there are stored gratings on the reference wave which must be illuminated, and it is able to be diffracted in such a way that only its partner object wave will appear, and it shows up on electronic camera.

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The holograph can be viewed by shooting either a white or a single-colored light beam (it varies) toward the reference beam.
Holographic storage is optical, as well as DVDs and CDs, but is still quite different from them. Light is stored as a 3-D hologram, taking up the whole volume of the cylindrical disc. To read the data, it is converted into 1s and 0s, unlike CDs and DVDs where lasers change the molecules to represent 1s and 0s.


Applications


With the possibility of having much more data stored in a smaller object, many companies and maybe eventually consumers will be able to carry around more data with them. As storage rooms in office buildings get smaller because of the use of electronic files and saving information on computers, they will continue to shrink as more data can be stored in a smaller space. As of now, this technology is still emerging and is being developed, so it is at the very beginning of its life cycle and people are still finding ways to make use of such a great new idea. However, some claim that it is a "nonexistant market." It is only write-once, read infinite times right now, so users can't use it to continually save and update information, but perhaps eventually that will come to be.

The technology could be used now in government, such as saving Social Security information of people, since it would most likely be accessed by a robotic-driven library. It could also be useful to banks or other financial information companies.

There is hope that these holographic storage devices can hold up to 50 movies, and they may as well be the best form of high-capacity storage by the year 2015, but still people are doubting that it will ever be successful. InPhase has already proven that it can hold 200 Gbit per square inch and run as fast as tens of megabytes per second.

Web Resources

Terminology