Holographic versatile disc

HOLOGRAPHIC VERSATILE

DISC

Outline

What is HVD? Collinear Holography. Basic structure How it work? Compare with other devices. Advantages/Disadvantages Conclusion

What is HVD ?

Holographic Versatile Disc (HVD) is an optical disc technology which would hold up to 3.9 terabytes (TB) of information.

It employs a technique known as collinear holography.

Collinear Holography

In collinear holography there are two type of laser beam.

Red beam(Information beam)

Green beam(Refrence beam)

This two beams are collimated in a single beam.

The green laser reads data encoded as laser interference fringes from holographic layer near the top of the disc.

while the red laser is used as the reference beam and to read servo information from a regular CD-style aluminum layer near the bottom.

A dichroic mirror layer between the

holographic data and the servo data reflects the green laser while letting the red laser pass through.

Basic structure

It has similar to CD-DVD structure. It is differs to use laser beams & its pulse speed.

The Components are like …

blue or green laser(532 nmwl),

red laser ,beam splitter, mirrors

special lights modulator(SLM),

C-MOS sensor ,photo polymer

recording medium.

What is next ?

0.7 GB 9 GB 30~50 GB

Optical Disc Technology

Holographic Versatile disc

How it works?

Current optical storage saves one bit per pulse & the HVD hopes to improve this efficiency with capability of around 60,000 bits/pulse.

Truncated cone shape that has 200 micrometer diameter at the bottom &

500 micrometer diameter at top.

Data-SLM-Binary

Data is created to fire laser beam into the beam splitter to produce 2 beam.

1.Reference beam ( Directed to away from the SLM). 2.Information beam ( Direct toward – the SLM ).

The 0’s & 1’s data pages are translated into the pixel of the special light modulator that either block or tr-

ansmit light.

A memory system isn't very useful if you can't access the data you've stored.

Advantages

HVD have the capacity to hold up to 3.9 terabytes (TB) of information, which is approximately 5,500 times the capacity of a CD-ROM,830 times the capacity of a DVD,160 times the capacity of single-layer Blu-ray Discs.

The HVD also has a transfer rate of 1Gbits/s(128MB/s).

Records one program while watching another on the disc

Interactive movie features.

Backward Compatible: Supports CDs & DVDs also

Disadvantages

Holography memory has

been around for more than 40 years

but several characteristic made it difficult to implement , now progras

of HVD make it easy to implement.

It is not available in market.

HVD will soon replace previous DVDs.It is currently supported by more than 170 of the

world's leading consumer electronics, personal computer, recording media, video game and music companies.

The format also has broad support from the major movie studios as a successor to today's DVD format.