Holographic Laser Cubes The method of storage for the future!! By: Eric Unterhoffer

Introduction A revolutionary new system of storage that is still in the experimental stages of development. Has been an ideology for almost 25 years by leading scientists. First prototype developed by Stanford University. Major companies in the industry such as IBM, Rockwell, Lucent Technologies and Bayer Corporation. Working in some cases as part of research consortia organized and co- funded by the U.S. Defense Advanced Research Projects Agency (DARPA).

Current Capabilities Similar to the constant stream of photographs from LANDSAT (Land Remote Sensing Satellite System) satellites.(1) Capable of storing hundreds of billions of bytes of data and downloading at a rate of hundreds of billions of bytes per second with a very high degree of accuracy.(1) Essentially a hundred times faster then any storage device available today.(1) Capable of storing video, sound and data.(1)

Current Capabilities Can retrieve images at real time rates with an accuracy of 1 error in 1 million bytes of data.(1) Lab results verified the capability to store 1 hour of video imagery in a single centimeter of cubic space or the size of a sugar cube.(1)

Testing Digital encoding techniques had to be invented with in the crystal in order to avoid difficulties with noise and imperfections of the crystal. (1) Because components that happened to be available in the laboratory were used on the project, the one-part-per- million error rate was worse than can be attained with current techniques. (1)

Testing Holograms were gradually erased after many scans by the readout laser. However, previous research has shown that an efficient hologram "fixing" method exists so holograms can be permanently stored in lithium niobate. (1) Recording time also was slow, taking one hour to store just over 160 kilobytes of data due to experimental materials. Testing of many different materials will be the only result in advancement of project. (1)

Functionality Holographic laser cubes currently use a material known as lithium niobate which is looks like a clear crystal block. (1) Holographic storage uses laser beams to record information in the form of two-dimensional holograms, one "page" at a time inside special optical materials. The image of the data can be read by shining a laser into the same volume of material. By changing the angles of the writing and reading laser beam, many pages of information can be stacked in and retrieved from the same space with a minimal amount of time. (1)

Functionality The general idea of the way the first demonstration works is two slim laser beams converge in the interior of the device. The crystal glows green which is invisible to the viewer. The patterns of electrons inside the clear block are rearranged and a series of images are stored. Next, one beam searches the cube alone. It reflects the pattern of those rearranged electrons and relays them to a video camera, which is then relayed to a computer. (2)

Actual Functionality (1&2) Works by converting video images into compressed digital data or “Pages”. It is then applied with designed software to apply error correction codes and then beamed from a laser through a device called a spatial light modulator to focus that data onto the lithium niobate crystal. A special mount moves the crystal three one- thousandths of a degree as each "page" is recorded in a clear pattern of opaque squares similar to a crossword puzzle.

Actual Functionality (1&2) The hologram is created when the object beam meets the second beam or reference beam and the two beams interfere inside the photosensitive material. Physical or chemical changes occur inside the cube to create the cross word like pattern. The pages are read back through a second laser or reference beam that reflects the recorded data to a charge- coupled device (CCD), similar to a camera.

Actual Functionality (1&2) The pattern is illuminated with one of the original beams and then diffracts the light to reconstruct the other beam thus recreating the original pattern. Finally The data is relayed to a computer, decompressed, and checked for errors using the error correction code.

Actual Functionality

Issues Finding the right storage material is presently the main issue in the development of holographic laser cubes. Materials such as photorefractive, photochromic and photochemical polymers have been tested so far. Finding the right material is important because it will determine life span of data, speed and space for the device. Present materials only allow for a maximum of 6 months for data life. Other issues is the data uploading rate is extremely slow.

Predicted Capabilities (2) There a predictions that holographic laser cubes will be capable of storing 1 terabyte or 1 trillion bytes of data in a single centimeter cubed or the equivalent size of a sugar cube. Will be able to read out information at a rate of 1 gigabyte or 1 billion bytes per second. Holographic storage devices are predicted to completely eliminate the days of magnetic storage devices.

Future Applications Imagine the capability of 6,840 raw uncompressed high quality Video/TV hours, or 2,100,000 chest x-rays, or nearly 10,000,000 high-resolution images, or 30,000 four- drawer filing cabinets of documents, or, or 20,000 DVD'S Worm's, or 4,000 BLU-Ray Worm disk's on ONE 10 Terabyte 3.5 in. removable disc.

Future Applications Another predicted possible application could also be with companies who wish to sell multimedia products such as music or movies over the internet. Because of the laser cubes large capacity and fast readout rate, huge movies could be watched with out a problem from huge archives.(1)

Final Thoughts Holographic laser cubes are the wave of the future, think about it in this context. With current technology a 1cm^3 laser cube is equal to: MB floppy discs MB CD-ROMs GB DVDs GB hard drives

Final Thoughts With predicted technology a 1cm^3 laser cube is equal to: MB floppy discs MB CD-ROM’s GB DVD’s GB hard drives

Bibliography 1) 2) 3) Other cites:

Thank you for listening to my presentation! The future is here!