HOLOGRAPHIC TECHNOLOGY

ABSTRACT

Title - HOLOGRAPHIC TECHNOLOGY

-How moving images are moving product

Holographic Storage is an optical technology that allows 1 million bits of data to be written and read out in single flashes of light. Thousands of Holograms can be stored in the same location throughout the entire depth of the medium. Unlike other technologies that record one data bit at a time, holography allows a million bits of data to be written and read in parallel with a single flash of light. This enables transfer rates significantly higher than current optical storage devices. This technology is used in various fields such as Data Storage, Holographic Images, anti counterfeit security systems etc. Further High storage densities, rapid read rates, High fidelity data recovery, High fidelity imaging of data pages, Low levels of noise in data recovery and long life create many new and exciting application areas for remote Holographic Technology. Combining high storage densities, fast transfer rates, with durable, reliable, low cost media, make holography poised to become a compelling choice for next-generation storage and content distribution needs.

HOLOGRAPHIC TECHNOLOGY

-How moving images are moving product.

1. INTRODUCTION

Holographic Storage is an optical technology that allows 1 million bits of data to be written and read out in single flashes of light. Thousands of Holograms can be stored in the same location throughout the entire depth of the medium. The word hologram is derived from Greek meaning ‘whole picture’. A hologram creates a real 3-D image by reconstructing the light waves that were reflected from the original scene or object.

In 2002, it was estimated that people produced 5 exabytes (5 billion gigabytes) of data [1], the majority of which was in digital form. Since this figure is always growing and analogue media is constantly being converted to digital, new methods of storing this data are needed. Currently the two main storage methods i.e. magnetic and optical are just about keeping ahead of these needs; unfortunately this is not always going to be the case. The limit of hard drive storage is expected to be reached within the next ten to fifteen years [2]. By then magnetic bit sizes will be so small that phenomenon such as the super paramagnetic effect (SPE) and shot noise will cause the polarity of the magnetic fields to flip randomly. Likewise, optical disks such as DVDs may reach their maximum capacity due to the diffraction limit of the laser light used.

One technology that may save us from an information overload is holographic data storage (HDS). Holography breaks through the density limits of conventional storage by going beyond recording only on the surface, to recording through the full depth of the medium. Unlike other technologies that record one data bit at a time, holography allows a million bits of data to be written and read in parallel with a single flash of light. This enables transfer rates significantly higher than current optical storage devices. Combining high storage densities, fast transfer rates, with durable, reliable, low cost media, make holography poised to become a compelling choice for next-generation storage and content distribution needs. In addition, the flexibility of the technology allows for the development of a wide variety of holographic storage products that range from handheld devices for consumers to storage products for the enterprise. Imagine 2GB of data on a postage stamp, 20 GB on a credit card, or 200 GB on a disk.

Hologaphic images are another major application of Holographic Technology. There are no practical barriers to using its holographic actuation and control technology to improve and enhance many types of electronic equipment, such as automotive, banking, factory-floor, gaming, kiosk, leisure, medical, military, personal and home electronics and toys, just to name a few. Holographic optical elements make lights brighter, CD-ROM drives work faster and machines see better. Holograms can serve as anti-counterfeit security devices etc.

In this paper we will deal about what is Holographic Technology and how it works? It also includes its benefits and its applications in Data Storage, Holographic images, Anti Counterfeit Devices etc.

2. What is a Hologram?

Th

1) The intersection of two               2)A photosensitive medium           3)The hologram is the       4) Light from one beam

beams creates interference           records the interference                image of the interference      shining on the

pattern of bright  and dark                pattern.                                            pattern stored within the        hologram reconstruct regions.                                                                                          medium.                                  the data pattern    

3. How is data recorded?

Light from a single laser beam is split into two beams, the signal beam (which carries the data) and the reference beam. The hologram is formed where these two beams intersect in the recording medium.

    

The process for encoding data onto the signal beam is accomplished by a device called a spatial light modulator (SLM). The SLM translates the electronic data of 0’s and 1’s into an optical "checkerboard" pattern of light and dark pixels. The data is arranged in an array or page of around a million bits. The exact
number of bits is determined by the pixel count of the SLM.

    At the point of intersection of the reference beam and the data carrying signal beam, the hologram is recorded in the light sensitive storage medium. A chemical reaction occurs in the medium when the bright elements of the signal beam intersect the reference beam, causing the hologram stored. By varying the reference beam angle, wavelength, or media position many different holograms can be recorded in the same volume of material.

5. How Is Data Read?

In order to read the data, the reference beam deflects off the hologram thus reconstructing the stored information. This hologram is then projected onto a detector that reads the data in parallel. This parallel read out of data provides holography with its fast transfer rates.

5. Benefits of Holographic Technology

• Dynamic Range

      High storage densities and rapid read rates

• Photosensitivity

      Rapid read rates

• Millimeter Thickness

High storage densities

• Dimensional Stability

High fidelity data recovery

• Optical Flatness

High fidelity imaging of data pages

• Low Scatter

Low levels of noise in data recovery

• Non-volatile readout

No unwanted erasure

• Long shelf-life of media

Approximately five years

• Long archival life of stored data

Thirty years

• Environmental/thermal stability

Competitive with other optical technology

6. APPLICATIONS

6.1 Holographic Data Storage

Holographic memory is a new optical storage method that can store 1 terabyte (= 1000 GB) of data in a crystal approximately the size of a sugar cube.  In comparison, current methods of storage include CD’s that hold 650 to 700 MB, DVD’s that store 4.7 GB, and computer hard drives that hold up to 120 GB. 

Advantages of HDS over conventional storage methods

Firstly, data is stored in all three dimensions of the material and not just the surface. This 3D aspect allows for a phenomenon known as Bragg volume selectivity to be utilized, whereby many information-laden holograms can be multiplexed (i.e. superimposed) in the same volume of medium. It is necessary to 'Bragg detune each recorded hologram with respect its’ neighbours. This can be achieved in a number of ways, for example rotation of the media with respect to the recording object and reference beam, or changing the wavelength or phase of the recording laser beams with each new hologram recorded. A page of data can then be read out by illuminating the material with an appropriate reference beam. This makes for an inherently more efficient storage medium. Read/write speeds are also much higher since data is written and read out as 2D digital or analogue images in a 3D volume rather then a bit stream. An example of data pages that were written in the photopolymer developed in the IEO can be seen in figure 1. The bit rate error [3] is also decreased considerably because error causing factors such as scratches, dust, etc tend to affect the surface only and since a hologram is recorded as a complex interference pattern in the bulk of the material, these affects are limited.

6.2 HOLOGRAPHIC IMAGES

Holographic interfaces empower operators to enter commands and data into a wide range

of electronic equipment by simply passing a finger through holographic images of what would otherwise be the keys of a keypad or keyboard, appearing to float in the air at a convenient location in front of the equipment.  An infrared sensor scans the plane of those images to detect the intrusion of a finger into the desired portion of those images, identifies which number or symbol has been selected and transmits that selection to the equipment's internal software, much the same way pressing a button on any ordinary keypad would.

    Holographic images solve many problems posed by conventional, tactile keypads and keyboards, particularly those regularly subject to contaminants, customer abuse, dirt, moisture, temperature fluctuations and shock.  Some of the benefits of interfaces using holographic actuation and control technology are:

• Human-friendly, easy-to-use     interfaces that provide comfortable, reliable operation of equipment where conventional, tactile interfaces sizes have shrunk below normal finger size.
• No wear with repeated operation because Holographic images interfaces have no moving parts to fail under normal or even heavy use.
• Holographic images interfaces are cost-effective, both initially and over time.
• Sterile operation - whether in healthcare settings or high-traffic consumer applications such as kiosks, Holographic images interfaces neatly bypass contamination issues because nothing need be touched to use them.

6.3 Anti Counterfeit System

Anti-counterfeit security is an attempt to prevent valuable products or documents from being copied or falsified. We use the term "copyright owner" generically to mean anyone

who has an interest in preventing counterfeiting, such as a government, a name brand manufacturer, or an intellectual property owner? The copyright owner, the product being counterfeited, the end users of the products, the distribution channels' the methods or technologies used to deter counterfeiting, and, finally, the counterfeiter, are all part of the anti- counterfeiting security system.

    Holography offers certain advantages as a security device. First, producing an original hologram is expensive and time consuming, but mass-produced replicas from the original are relatively inexpensive. Second, the equipment and skills necessary for mass producing holograms has been fairly difficult to obtain in the past. Third' holograms look distinctively different from printed labels. Fourth, the tools counterfeiters have traditionally used for counterfeiting (the camera and the printing press) do not work on holograms.

    At the same time, holography has disadvantages. Because most holograms are embossed, mechanical copies are relatively easy to make. A skilled holographer can make optical copies of holograms that are very difficult to distinguish from the originals. And, once a good master copy has been made, high quality replicas are very easy to make.

    Despite some disadvantages, holography is currently an effective counterfeit deterrent. However, if holography companies want to continue to enjoy a high share of the anti-counterfeit security market, they must look to the future. They must realize that today's

Hologram technology has become relatively easy and inexpensive to obtain, and hologram counterfeiting will surely become both feasible and profitable in the relatively near future.

6.4 Other applications

·  Holographic optical elements (HOE’s) are used for navigation by airplane pilots.  A holographic image of the cockpit instruments appears to float in front of the windshield.  This allows the pilot to keep his eyes on the runway or the sky while reading the instruments. This feature is available on some models of automobiles.

· Holograms are used in advertisements and consumer packaging of products to attract potential buyers.

· Holograms have been used on covers of magazine publications.  One of the most memorable Sports Illustrated covers was the December 23, 1992 issue featuring Michael Jordan.  Holograms have also been used on sports trading cards.

·  The use of holograms on credit cards and debit cards provide added security to minimize counterfeiting.

·  Holography has been used to make archival recordings of valuable and/or fragile museum artifacts.

·  Sony Electronics uses holographic technology in their digital cameras.  A holographic crystal is used to allow the camera to detect the edge of the subject and differentiate between it and the background.  As a result, the camera is able to focus accurately in dark conditions.

·  Holography has been use by artists to create pulsed holographic portraits as well as other works of art.

6.5 Future applications of holography include:

·  Future colour liquid crystal displays (LCD’s) will be brighter and whiter as a result of

Holographic technology.  Scientists at Polaroid Corp. have developed a holographic

reflector that will reflect ambient light to produce a whiter background. 

·  Holographic night vision goggles

· Many researchers believe that holographic televisions will become available within 10 years at a cost of approximately $5000.  Holographic motion picture technology has been previously attempted and was successful in the 1970s.  The future of holographic motion pictures may become a reality within the next few years.

· Optical computers will be capable of delivering trillions of bits of information faster than the latest computers.

7. CONCLUSION

The High storage densities, rapid read rates, High fidelity data recovery, High fidelity imaging of data pages, Low levels of noise in data recovery and long life create many new and exciting application areas for remote Holographic Technology. The spread of hologram technology will soon reduce the value of ordinary embossed holograms as anti-counterfeit devices. On other hand, advances we foresee in recording materials, hologram recording systems and embossing substrate materials should greatly increase the security value of holograms within three or four years. This make holography poised to become a compelling choice for next-generation storage and content distribution needs. In addition, the flexibility of the technology allows for the development of a wide variety of holographic storage products that range from handheld devices for consumers to storage products for the enterprise.

8. References

[1] Peter Lyman and Hal R. Varian, how-much-info@sims.berkeley.edu.

[2] D. A. Thompson, J. S. Best, “The future of magnetic data storage technology”, IBM J. Res. Develop. Vol. 44 No. 3 May 2000.

[3] Hoffnagle J A and Jefferson CM 2000 Holographic Data Storage ed H J Coufal, D Psaltis and G T Sincerbox (New York: Springer) pp 91-100.

[4] The Holography Handbook, by Fred Unterseher and co-authors Ross Books, 1987.