Presented by: Dr. Richard Billmers Triple Take Holographics For Holo-pack Holo-print 2012.
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Transcript of Presented by: Dr. Richard Billmers Triple Take Holographics For Holo-pack Holo-print 2012.
A MULTISPECTRAL APPROACH TO
HOLOGRAM SECURITY
Presented by:
Dr. Richard Billmers
Triple Take Holographics
For Holo-pack Holo-print 2012
Presentation Roadmap
1. Introduction - Who are we?
2. Previous Work in Volume Holography
3. Salient Features of Security Holograms
4. Concept for M.S. Approach to Holographic Security
5. Advantages of this M.S. Approach
6. Summary and Conclusions
Introduction – Who We Are
Collaboration of Triple Take Holographics and RL Associates Inc.
TT has been doing HOE and display holography development for over 20 years.
RL Associates has been doing HOE development for 15 years
Both are mainly design and prototype development companies. Mostly gov’t (DOD, NASA and Homeland Security) funded under R&D programs.
Both of our business models would be to develop this process and then license it to a much larger holographic production company.
Lidar Receiver with 2-Element Filter
Volume Holographic array near the focal plane of large aperture mirror Beam shaping with spherical
holograms Light from wide FOV reflected
as collimated beam Second narrowband element
filters collimated light Filtered light focused to small area
detector.
Operating Wavelength: 473 nm
Spectral Bandpass: 0.12 nm, FWHM
Clear Aperture (Array): 45 mm diameter
Efficiency: 50%Out-of-Band Blocking: 10-4
Field of View (@ Primary): 3.5° at 16.5” aperture
Delivered Prototype March 2011
Optical Design of Lidar Receiver Parabolic Primary Mirror
SPDT, Ni-plated Al 420mm CA, f/0.9 Coated for 400-550nm
Holographic Array (Secondary) 1027 elements, 1.49mm diam.
○ 127 multiplexed elements
Array Spherical-planar Geometry Tailored to field near focal plane of
16.5” primary mirror ~20° FFOV per element
Aft optics include: Narrowband filter 1/99 Beamsplitter 2x 8mm PMTs
Holographic Beamsplitting Approach
Current Approach: Interference filters Passes wavelength of interest/blocks all other wavelengths One filter in front of each camera Inefficient and uses multiple lens systems (1 for every camera)
Holographic Approach Split the incoming white light All light is captured 5-6x more efficient & single lens system with same zoom on all
channels
CollectionOptics
MultiplexedGratings
Camera1
Camera2
Camera3
White LightIn Field of View
CameraArray
CollectionOptics
MultiplexedGratings
Camera1
Camera2
Camera3
Camera1
Camera2
Camera3
White LightIn Field of View
CameraArray
Operating spectrum: 450 – 800 nmNumber of spectral channels: 12Spectral bandpass/channel: 15-25 nm, Field of view of system: 20-25 deg.Efficiency: 65-75%Aperture of system: 2” x 2”Aperture of each grating: ½” squareOut-of-Band rejection: 10-2
Photo of 12 channel beamsplitter element
Beamsplitter Characteristics
12 channel Beamsplitting Element Demonstrated
12 channel Beamsplitting Element Demonstrated (cont.)
12 Camera Bank
Volume Holograms:Tri-MultiplexedQuad-Array
1 1 1 2 2 2
43 443 3
1
3
2
4
12 Camera Bank
Volume Holograms:Tri-MultiplexedQuad-Array
1 1 1 2 2 2
43 443 3
1 1 1 2 2 2
43 443 3
1
3
2
4
450 500 550 600 650 700 750 8000%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100% BeamSplitter Array453 Band 464 Band483 Band 496 Band513 Band 531 Band576 Band 598 Band620 Band 655 Band681 Band 781 Band
Wavelength, nm
DE, %
5 Channel MSI: 3 underwater/1 surface & MWIR
View Through Aperture of Turret MountShell inside turret, 5.1” Ø
Sensors:Active Area, blkChip, gold
Zoom Lens system (shared),Apt: 2” Ø
Muxed VHOEs,behind vis. sensors
• Multispectral Imager using 4 volume multiplexed reflective holograms– 3 blue/green channels for underwater detection– 1 red channel for surface reflection
• MWIR Channel w/shared lens system
Cross-section
Step Zoom Lens System
Mux’dVHOE
4.8” (122 mm)
5.1” (130 mm)
CH1 (above)CH2 (below)
CH3 (below)CH4 (above)
MWIR Sensor
Visual Image On board processing
Photos courtesy of JMMES program, NavAir, EO Sensors division
and BAE Systems, Honolulu, HI
Use of Holograms as a Security device for 30+ years
Relied on the rarity of the specialized skills and knowledge
Expensive, custom-built equipment needed
These limitations diminished as the process became a recognised industry
Skills and process could be learned on the internet
Equipment is more common and cheaper
To continue to combat anti-counterfeiting in the digital age, security aspects of holography have to become more sophisticated
Salient Features of Holography in Security
1. Overt security
2. Covert Security
3. Tamper Evident
All three are specifically mentioned in the new ISO 12931 Authentication Standard for Material Goods
Three Types Security Features of holograms:
Categories of Security Features of holograms:
1. Overt security
hologram is instantly visible
Image is recognizable
Unique look is difficult to emulate by non-holographic means
However, if copied holographically, even a poor copy will pass a casual inspection
Categories of Security Features of holograms:
1. Covert security
Features embedded within the hologram
Not clearly visible, but may be discovered
Security relies on general ignorance of their existence or how to reveal them
As given features are used, their existence becomes more widely known, possibly diluting their status as covert
Categories of Security Features of holograms:
1. Covert security - examples
Hidden Imagery Laser viewable only Requires knowledge of correct laser angle to display Best revealed using custom display reader
Micro-structures Microscopic designs recorded directly onto the surface can be seen with loop or microscope Dot matrix images with shaped dots
Hybrid: Electron beam images which replay with a laser beam
Categories of Security Features of holograms:
1. Covert security - examples (cont.)
Hidden Geometric Variations altering the geometry or shape of dots in a dot matrix can be discovered with microscope but not easily copied
Luminescent overlays dyes that glow under UV color-tuning film overlay
Categories of Security Features of holograms:
1. Tamper Evident - examples
Exists within the structure of the material
Does not show in the hologram, covert
Revealed when tampering occurs, becoming overt
The essence of any security feature is incumbent in:
Difficulty of reproducing by unauthorised user
Simplicity of decoding by genuine user
Cost and ease of implementation of the feature
Most Present methods satisfy criteria independently
Some may be mutually exclusive – Most of the time the more complex the feature, the more complex is the implementation
More complexity typically means that it is more costly to design, build and implement.
Possible Applications for Multispectral Holographic Security
Banknotes
Credit Cards
Material Goods - as per ISO 12931
Pharmaceuticals
Printed Store or Manufacturers’ Coupons
Document Security
Multispectral Approach - The Concept
1. Multiple diffraction gratings are recorded in the same volume in a patch configuration.
All gratings are recorded with same laser.Each grating is tuned so that a specific incoming angle/wavelengthcombination is reflected in a known geometry. Planar or spherical.
2. The number of gratings recorded is variable depending on the level of security required. Furthermore gratings can be spherical to focus at some given distance. This is just another level of security.
3. The gratings are read-out and verified using a set of LED’s (not laser) at specific wavelengths. The reflected light is detected by a set of PIN or similar diodes at very specific angles and distances (for spherical gratings).
4. A set of very simple electronics (voltage comparators. AND/OR gates) would then determine automatically if the proper signals were incident on the proper detectors
A Multi-Spectral Approach - Implementation
Multispectral Approach - The Concept Illustrated
Multi-Spectral Approach – Not Authenticated
Multi-Spectral Approach – Not Authenticated
Multi-Spectral Approach - Variations
-
A Multi-Spectral Approach – Not easily copyable
A Multi-Spectral Approach – Not easily copyable
A Multi-Spectral Approach
Satisfies all three criteria above
Difficult for unauthorised duplication# of source / detector combinations goes up factoriallyCombinations can be exclusive, or changed easily
Decoded using a simple, inexpensive reader that would provide a YES/NO answer with no additional skills or training required of the operator.
Can be mass-produced with equipment already available and present levels of training.
Advantages of a Multi-Spectral Approach
Conclusion
We believe we have developed a method of recording a security feature on holograms that is simple and cheap to implement, simple to use in the detection of fraudulent product, and highly flexible so that the security aspect can be easily customized.
THANK YOU
Triple Take Holographics
would like to thank our partner
R. L. Associates, Inc
for their support in this project