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