Physical Optics Corporation 1845 W. 205th Street, Torrance, CA Phone: , Program Manager: Min-Yi Shih,

Transcription

1 Robust Holographic Optical Memory (RHOM) ITEA 2012 Test Instrumentation Workshop Physical Optics Corporation 1845 W. 205th Street, Torrance, CA Phone: , Program Manager: Min-Yi Shih,

2 Targeted Problem: T&E Need for New Massive Onboard Data Storage T&E/S&T Challenge: To address the increasing demands of massive data storages for T&E applications, the U.S. Army Program Executive Office for Simulation, Training, and Instrumentation (PEO STRI) is seeking advanced massive onboard data storage technologies under the Advanced Instrumentation Systems Technology (AIST) focus area of the Science and Technology (S&T) Challenges. Specifically, the required data storage device should have following characteristics: High Data Capacity: multi-terabytes and beyond High Data Density: low volume Low Weight Field Environments and High Survivability Zero Volatility 2

3 Project Description: POC s Robust Holographic Optical Memory (RHOM) The system is made possible through the application of: 1. Phase multiplexing (based on Denisyuk s orthogonality) for high data capacity 2. Digital signal processing (DSP), including LDPC ECC, to approach Shannonlimited signal detection with error-free recovery for zero volatility 3. POC s extensive experience in photopolymers and holographic media 4. POC s experience and expertise in hardened d onboard recorders for avionic i platforms 3

4 POC s RHOM, Digital Holographic Storage g Innovative fusion of three main enabling technologies: Orthogonal phase multiplexing (Denisyuk s orthogonality) holographic data storage technique using distributed volume optics for realization of full capacity of holographic optical memory New photopolymer volume holographic recording material with low noise, high h sensitivity, and high h dynamic range, allowing more holograms to be recorded Advanced d digital it signal processing (DSP) for data coding, and optical homodyne detection to enhance signal-to-noise ratio (SNR), providing improvement of orders of magnitude in readout data rate (10 Gb/s and beyond), and storage capacity 4

5 RHOM Basic Optical System Layout Phase SLM (Ref.) Waveplate Optical Beamsplitter Laser Waveplate Compact Holographic Optical Element (HOE) Waveplate Phase SLM (Data) CMOS Holographic Recording and Storage Medium Waveplates for Polarization Conditioning 5

6 Implementation of Orthogonal Phase- Reference Recording and Readout Development of orthogonal phase referencing method Number of orthogonal Walsh Function (for a 2 n x 2 n array) N w = (2 n -1)(2 n -1) 1 million pages are anticipated to be stored and retrieved through phase coded reference and signal (data) beams (Denisyuk s Orthogonality ) and homodyne detection, i.e. conversion of phase in amplitude modulation on readout. In 90 deg geometry the actual number of pages is determined by the M# of the material [>5000 have been demonstrated t d (Northrop)]; homodyne detection ti allows to reduce the minimum holographic diffraction efficiency (HDE) 10 to 100 times and increase the number of pages: Examples of binary-phase patterns (Walsh functions) Examples of COTS SLMs 6

7 RHOM Orthogonality Experiment A number of holograms were recorded on lithium niobate crystal and reconstructed using different Walsh functions Orthogonal phase patterns were generated by using Walsh function for reference phase SLM, and random 2D digital binary patterns were used for data SLM for the recording In the reconstruction or readout, the reference beam corresponding to the particular Walsh function was used to reconstruct the data, which is captured by a CCD camera The orthogonality verification was done by recording the holograms with orthogonal phase patterns and reconstructing with other orthogonal patterns 7

8 RHOM Orthogonality Experiment at POC Laser beam Mask1 HWP PBS HWP BS Reference beam Expander lens Holoeye PO-SLM Mask2 Fourier Lens Data SLM Object beam Mask3 Camera LiNbO3 crystal 8

9 RHOM Orthogonality Experiments: Playing Back with Same Walsh Function Five samples out of the 48 SLM images recorded using 48 different Walsh function reference beams. SLM images Walsh functions used for recording Reconstructions using the same Walsh function Reconstructions using different Walsh functions 9

10 Recording Material Selection Maximum number of holograms*: Comparison of media storage capacity (T = 10 mm, = 405 nm, η min = 10-6 ) Material M# Dn max N max Fe:LiNbO 3 (90 ) [1] 0.1 mm ~1,000 PQ doped PMMA [2] 17mm ,000 Tapestry current [3-4] 20 mm ,000 Tapestry DRED [4] 80 mm ,000 * Holographic Data Storage, Springer-Verlag g Series in Optical Sciences, H.J. Coufal, D. Psaltis, and G. Sincerbox, eds G. W. Burr, HighDdensity Storage in Fe:LiNbO 3, Opt. Letters publications 2. D. Psaltis, Caltech, presentation at HDS Workshop, Arturo Hale, Lucent Technologies, presentation at HDS Workshop, Fred Askham, presentation at POC, 2011 With 1k 1k SLM size, N max = 800, holograms translates t into ~0.8 Tb capacity per storage cube. Objective: Develop ppractical and robust approach to produce multi-tb/cm 3 Investigate and realize the full potential of unique holographic operation and technologies, such as associated memory 10

11 High Optical Quality Photopolymer Media Made by POC Demo media cube proving viability of manufacturing media in required thick form factor with good optical quality. High optical quality media package for breadboard prototype /5 BK7 high-precision windows 10 x 10 mm internal cross-section 12.5 x 12.5 mm face dimension 3 mm thick substrate AR V-coat on outside surfaces <0.1% 405 nm 11

12 RHOM Comparison w/ State of the Art Approach InPhase Holographic disk drive (300 GB) using Technologies proprietary p 1.5 mm thick blue-sensitive photopolymer medium STX Aprilis, Inc. Holographic disk medium: >100 b/ m 2 demonstration using 400 m thick photopolymer and combination of angular and peristrophic multiplexing Stanford Univ. 10 Gb/s digital holographic photopolymerbased rotating-disk storage system (DARPA) Notes Moving parts, bulky optics, drive size is large (18 in. deep) Moving parts, bulky optics Moving parts, bulky optics IBM Almaden 90 recording using Fe:LiNbO 3 and angular Moving parts, bulky optics, large system multiplexing (>240 b/ m 2 demonstrated) footprint of 0.8x0.8 m 2 ) NASA JPL POC s RHOM No moving parts, angular multiplexing using LC phase-only spatial light modulator (POSLM) or MEMS device Compact, Large capacity (>10 Tb/module), High data rate (1 Gb/s) Digital performance not reported, full capacity not demonstrated, radiation hardening is difficult due to semiconductor nature of the lithium niobate recording material Previous development of 3D HAM for DOE SBIR, extensive experience with photopolymer medium and flyable system integration 12

13 Summary To address the DoD T&E/S&T need for advanced, onboard, massive data storage, POC has begun the development of a new Robust Holographic Optical Memory (RHOM) and: Developed practical (risk-reduced) RHOM system architecture and path for scaling from >1 TB to exabyte (10 6 TB) storage capacity Experimentally verified phase-coded Denisyuk orthogonality (a major technological breakthrough and major risk reduction) Developed new photopolymer media in-house Developing RHOM major and critical subsystems and components and begun fabricating a breadboard prototype system at TRL = 4 13

14 Partnership of RHOM Development Collaborations for RHOM development within military T&E community: Army White Sands Missile il Range, Edwards d Air Force Base, and dboeing (St. Louis Engineering, Operations & Technology business unit) Leverage POC s own experience in avionics technology transition Digital it Data Set (DDS) for T-45 platform Data-Centric Flight Data Recorder for: Sikorsky C76++ aircraft Boeing Dragonfly UAV Certifications: FAA TSO, ED 112 Development and manufacturing process compliance: ISO 9001:2001- and AS9100-certified manufacturing lines Navy- and FAA-approved production facility Qualification test facility, ATP, SITP 14

15 Acknowledgement This project is funded by the Test Resource Management Center (TRMC) Test and Evaluation/Science & Technology (T&E/S&T) Program through the U.S. Army Program Executive Office for Simulation, Training and Instrumentation (PEO STRI) under Contract No. W900KK-I1-C-0022* Government Lead: Dr. George T. Shoemaker Collaborations: Army White Sands Missile Range, James Cutler Edwards Air Force Base, Benigno Castillo *Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the Test Resource Management Center (TRMC) and Evaluation/Science & Technology (T&E/S&T) Program and/or the U.S. Army Program Executive Office for Simulation, Training, & Instrumentation (PEO STRI). 15