FIBER OPTIC & FIBER LASER HISTORY & AMERICAN OPTICAL Jeff Hecht Author, City of Light: The story of fiber optics Contributing Editor, Laser Focus World

Hecht fiber history 1

1841 Colladon's Fountain Total internal reflection

Water-air interface

Guides along parabola Scattering in water Sparkling at turbulence Dark at smooth areas

Hecht fiber history 2

Paris fountains at night 1889

Hecht fiber history 3

Origins of imaging fiber bundles Patented 1930, Clarence W. Hansell

Demonstrated 1930, Heinrich Lamm

Reinvented after World War II

Hecht fiber history 4

Postwar fiber optics

Holger Mller Hansen Harold H. Hopkins

Hecht fiber history 5

The Road to AO

A.C.S. Van Heel Brian O'Brien

Hecht fiber history 6

A full agenda at AO

Van Heel's bundle Todd-AO Oklahoma

O'Brien Jr, Todd, Fred Zinnermann, O'Brien Sr, Hammerstein

Hecht fiber history 7

Brian O'Brien and Will Hicks

Brian O'Brien

Told CIA that fiber bundles could scramble images

Did nothing for months Busy with Todd-AO Briefed Hicks

September 1954 gave him 2 plastic-clad fibers

Went back to Todd-AO

Will Hicks

Physicist Furman U, UC Berkeley

Working on fibers for Milliken Research Trust Textiles, not glass

CIA hired him for AO Assignment

Make and clad fibers Assemble into image

scrambler

Hecht fiber history 8

The O'Brien fiber patent Voided because it was filed Nov. 19, 1954. Van Heel paper was published in Holland on 12/6/53 European style

Hecht fiber history 9

Will Hicks at AO

Validated need for cladding 'Cover story' medical imaging Real job image scrambler Crucible drawn fiber

Plastic coated Poor transmission Double crucible glass clad

Visits OSA Lake Placid meeting October 1956 Meets the competition

BOSSES Steve MacNeille Walt Siegmund

Hecht fiber history 10

University of Michigan

Basil Hirschowitz Larry Curtiss

Hecht fiber history 11

The Cladding Problem

Mller Hansen margarine Van Heel Beeswax Hicks/O'Brien plastic Michigan lacquer, plastic Hicks double crucible glass Curtiss rod-in-tube glass

Picked fire-polished rods Excellent quality Dec 1956 Needed 40 km of 40-m fiber to make 40,000-fiber flexible bundle

Cladding essential to prevent crosstalk Needed low-index transparent material But what would work?

Hecht fiber history 12

Hicks and the AO approach Progress stalled Lee Upton-AO glass

Collapsing glass tubes onto electrical components

Frederick Norton, MIT Millifiore glass

Stacking fiber, then drawing down

Rigid bundles Equipment delays

Hecht fiber history 13

Wikipedia art

Image scrambler demonstration Problems

Mechanical polishing Contaminants

Demonstration Looped fiber around drum Glued one region Sawed in half Scrambled fibers in middle Sawed in half again

Encoder/decoder pair Shipped to CIA

Vacation at last! Myrtle Beach Hicks realizes codes can

wear out Tells CIA only 18 uses

End of project Switches to faceplates

Bill Gardner Image intensifiers AO fails to develop

Hicks launches Mosaic

Hecht fiber history 14

Mosaic Fabrications Fiber-optic faceplates Image intensifiers Fiber tapers Fiber-optic Christmas tree

Hecht fiber history 15

Elias Snitzer joins AO Former professor at Lowell Tech

Shown bundle photo Identifies patterns as transverse modes

First single mode fiber With Hicks, Harold

Osterberg, Michael Polanyi

Develops mode theory

Hecht fiber history 16

Snitzer and glass lasers Began work in 1960 Neodymium-doped glass laser: 1961

Clad glass rods First fiber laser First fiber amplifier Later

Dual-clad fiber 1480-nm pumping

Hecht fiber history 17

Pioneering research

Dielectric waveguide modes First glass laser, in clad rod (thick fiber)

Hecht fiber history 18

Fiber amplifier

Hecht fiber history 19

Eli at AO Sep 1964 with big glass laser

Hecht fiber history 20

Trends in fiber communications Charles Kao proposed in 1966 Corning first low-loss fiber 1970

Fiber was single-mode

Bell Labs wanted multimode early 1970s Naval Research Lab used SM for sensing early 1970s Single-mode 'rediscovered' circa 1980

British Telecom Research Labs Japanese telecommunications companies Bell Labs submarine cable group

Global networks spread 1980s Interest in wavelength-division multiplexing Optical amplifiers to simplify design

Hecht fiber history 21

First revival of fiber laser End pumping Nd-doped fiber with laser

First with dye laser End pump with diode laser

Prompted by interest in fiber communications

Hecht fiber history 22

Doped fiber sensors Demonstrated 1983

Hecht fiber history 23

Doped fiber lasers to amplifiers David Payne at University of Southampton mid-1980s

Experiments with doped fibers Demonstrates laser action by end pumping with lasers Tests many rare earths in lasers Demonstrates erbium-fiber laser in 1.55-m band Demonstrates erbium-fiber amplifier in 1.55-m band

Importance of fiber amplifiers Optical amplification sought for fiber communications Semiconductor optical amplifiers were noisy Single-mode fiber zero dispersion wavelength 1.3 m Single-mode fiber minimum loss 1.55 m

Needed to be made practical for systems

Hecht fiber history 24

Snitzer OFC 88 postdeadline

Hecht fiber history 25

Diode pumping at 1480 nm

The importance of fiber amplifiers Can amplify many wavelengths simultaneously Allowing wavelength division multiplexing Multiplying fiber capacity by ~100-fold Vital for long-distance transmission

Submarine cables, continental backbone networks Developed in early 1990s

Just as Internet growth takes off Fueled growth of Internet and telecommunications Crucial element of global telecommunications network Fiber system capacity still growing

Spatial division multiplexing, multiple core, multiple modes 100s of terabits per second per fiber

Hecht fiber history 26

Snitzer OFC 89 postdeadline

Hecht fiber history 27

Double-clad or dual-core fiber

Evolution of Fiber Lasers Diode pumping Dual-core pumping Erbium fiber lasers

Communications Short pulse research Frequency combs

Ytterbium fiber lasers Industrial lasers Materials working lasers High-efficiency lasers

Advantages High efficiency High power Compact Reliable

Applications Industrial Instrumentation Research Medical

Hecht fiber history 28

Fiber laser efficiency Diode pumping

Converts electric power into pump light efficiently ~ 50% electrical to optical efficiency

Diode matched to absorption line Optical to optical energy conversion

Small photon deficit between pump and output High excitation and extraction efficiency

~ 60-70% optical to optical conversion efficiency

~25-35% wall-plug efficiency attainable Reduces energy requirements Reduces cooling requirements Reduces size and weight of laser

Hecht fiber history 29

NAVY LaWS (Laser Weapon System)

Hecht fiber history 30

Naval Sea Systems Command test integrated with Raytheon PHALANX for ship defense 6 5.5-kW fiber lasers combined to generate 30 kW Shot down UAV in marine environment, reported June 2010

Output beam quality BPP~10 M^2~33 DC EOE ~ 33% Output fiber core diameter 200um Output NA ~ 0.09 Output fiber length 15m Raman level at full power expected to

be ~ -35dB Linewidth (FWHM) ~5nm Weight ~ 2,500kg Size (HxWxD): 1.8m x 2.7m x 0.8m Delivered August, 2008 Has achieved 50kW in five states and

traveled > 10,000 highway miles

Hecht fiber history

50-kW multimode fiber laser

IPG photo

31

Precision cutting

Hecht fiber history 32

IPG Photonics

Femtosecond fiber laser - Calmar Passively modelocked Erbium 1530-1565 nm

100-500 fs 1-1000 mW avg 10-100 MHz

Er doubled 780 nm 100 fs, 10-50 MHz 10-50 mW avg

Yb 1030-1060 100-800 fs, 10-50 MHz 0.5 mW-5W avg Picosecond pulses

compressible

Hecht fiber history 33

PolarOnyx single-frequency fiber laser

Linewidth < 1 kHz 10-30 dBm output 1530-1565 nm Instrument or module Applications

Fiber gyros Metrology Coherent communications Sensing Spectroscopy

Hecht fiber history 34

Glass lasers

National Ignition Facility, Lawrence Livermore National Laboratory

Hecht fiber history 35

LEGACIES Ideas Inventions Enterprises

Hecht fiber history 36

Enterprises Will Hicks

Mosaic Fabrications Galileo Electro-Optics

1984 Inc. Set up in old industrial left Goal was huge

transmission capacity Sold to Polaroid 1982 Hicks hired Snitzer to run

company

Many more

American Optical Spun off glass lasers Continued fiber bundles Later sold to Schott

Fiber amplifiers Fiber lasers

IPG Photonics in Oxford Many other companies

Hecht fiber history 37

Thanks to Dick Whitney IEEE IEEE Photonics Society Richard Linke Gordon Day Optical History Museum