#SIG January ’14 IIT Roorkee Pathak Madhav Kiritkumar IIT Roorkee Holography & Digital Holographic Data Storage

Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 Outline of the Talk -Holography in News. -The fundamental Principles behind Holography -Understanding Holography -Difference between Holography & Photography -Different Methods of Data Storage -Holographic Versatile Disc -Holographic Storage Principles -Different Multiplexing Techniques -HVD- A Technology that never Picked up -Other Applications -Conclusion -Sources

The Buzz..

From Bricks To Building – Fundamental Concepts, Novel Technologies What are the fundamental Principles behind Holography ? Young’s Double Slit Experiment InterferenceDiffraction Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015

Understanding Holography In Short, Recording the Interference Pattern ! What is a Hologram ? How is it formed ? Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015

-The reconstruction of the original scene is done by shining the laser identical to the one used in recording. Understanding Holography Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015

The Difference Between Photography & Holography -Storage of Average Light Intensity over The Photographic Plate -- So, One Parameter -Storage of Interference Intensity + The Phase Information -- So, Two Parameter :Phase & Intensity Why is there a 3-D Image/Object Reconstruction unlike photography ? Supporting Equations : Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015

Data Storage -RNA & DNA might be the oldest data storage medium. Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015

Different Data Storage Modes Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 – Magnetic Storage Floppy Disk – Optical Storage Optical Disk, CD‐ROM, DVD – Electrical Storage ROM, RAM, Flash memory – Holographic Data Storage

Holographic Disc & Drives Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 -Storage densities as high as 100 Gbits/inch and data rates of 1.0 Gbits/s can be realized. -InPhase Technologies, a Technology Company spun out of Bell Labs delivered HVD with capacity of 300 GB, & transfer rates of 20 MB/s in read write mode in May,2008 -Upto 4 TB HVDs made at research Scale Why is such a high density data storage & access rate possible ?

Holographic Storage Principle Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January, A page is like miniature open and closed shutters, representing information to be stored. -A typical page would contain 1024 x 1024 bits

Holographic Storage Principle Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 Spatial Light Modulator : Eg. Liquid Crystal Display

Multiplexing Techniques Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 -The reference beam is a plane wave. -The reference beams and the optical axis of the signal beam lie on the same plane. -The address is determined by the angle of the reference beam. Angle Multiplexing, In Plane What decides angle resolution of the reference beam multiplexing ?

Multiplexing Techniques Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 -The reference beam is a plane wave. -The addressing scheme is the relative rotational position of the storage medium. -The axis of rotation is arbitrary, but typically it is chosen normal to the holographic medium Peristrophic Multiplexing

Multiplexing Techniques Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 -The reference beam is a plane wave -The addressing mechanism is the wavelength of incidence of the reference Wavelength Multiplexing

HVD – A technology that commercially never picked up ! Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 -Aprillis Inc. & Inphase Technologies, The major players nearly have shut down their operation from around The Holographic Data Storage faces material, operational and affordability issues -- Floppy C.D. DVD Blue-Ray DVD HVD -Internet, Cloud Storage, Pendrive - Higher Costs ~ $ 160/ Disc Are Technological Startup (Entrepreneurship) a risky business ?

Other Applications ! Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 Digital Image Resurrection !

Conclusion Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 -Holography based on principle of Interference and Diffraction. - A 3D Representation of Object or Person : Hologram -Digital Holographic Data Storage : Faster & Dense, Chunk by Chunk instead of bit by bit --Different Multiplexing Techniques, Storing multiple holograms (data) over same volume. --HVD (Holography Versatile Discs) -- The struggle to succeed in Commercial Market -- Holographic Image Resurrection & Microscopy picking up slowly. Data of one DVD

Sources Holography & Digital Holographic Data Storage Holography & Digital Holographic Data Storage 20 th January,2015 -Akonia holographics, startup in digital holographic storage domain -Musion, a technological company in holography -Different data storage comparison -Article on Current Status of Holographic Technology -A white paper on Holographic Data Storage submitted to Signal Lake, Venture Capital Company -Wikipedia

“In our Lab, Light Doesn’t Travel in Straight Line”

Acknowledgements -- Prof. Joby Joseph, IIT Delhi -- Ish Kumar Jain & Saurav Prakash, IIT Kanpur

? ‘Our World is 3-D, Let’s Record it that Way!’