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LLNL-CONF-423982
Precision Engineering within theNational Ignition Campaign
J. S. Taylor, K. Carlisle, J. L. Klingmann, P.Geraghty, T. T. Saito, R. C. Montesanti
February 18, 2010
10th International Conference of the European Society forPrecision Engineering & NanotechnologyDelft, NetherlandsMay 31, 2010 through June 4, 2010
Disclaimer
This document was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor Lawrence Livermore National Security, LLC, nor any of their employees makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or Lawrence Livermore National Security, LLC. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or Lawrence Livermore National Security, LLC, and shall not be used for advertising or product endorsement purposes.
Precision Engineering within the National Ignition Campaignthe National Ignition Campaign
Co-authors:Keith Carlisle
John S. TaylorJohn S. TaylorChief Engineer, NIF/NIC Target Fabrication Chief Engineer, NIF/NIC Target Fabrication Group Leader, Precision Systems and ManufacturingGroup Leader, Precision Systems and ManufacturingLawrence Livermore National LaboratoryLawrence Livermore National Laboratory
Jeffrey KlingmannPaul GeraghtyTed SaitoRichard Montesanti
This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under ContrThis work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contractact DEDE--AC52AC52--07NA2734407NA27344
Lawrence Livermore National LaboratoryLawrence Livermore National LaboratoryThe 10The 10thth International Conference of the European Society for Precision Engineering and Nanotechnology International Conference of the European Society for Precision Engineering and Nanotechnology Delft, the NetherlandsDelft, the NetherlandsJune 1June 1--3, 20103, 2010 LLNL-CONF-433952
John S. Taylor—10th euspen, Delft, June 1–3, 2010 2
NIF concentrated all 192 laser beam energy in a football stadium-sized facility into a mm3football stadium-sized facility into a mm3
John S. Taylor—10th euspen, Delft, June 1–3, 2010 3John S. Taylor—10th euspen, Delft, June 1–3, 2010
NIF is by far the largest and most complex optical system ever builtNIF i th l i ti fNIF is the culmination of
40 years of laser fusion R&D at LLNL
John S. Taylor—10th EUSPEN, Delft, June 1–3, 2010 4John S. Taylor—10th euspen, Delft, June 1–3, 2010 John S. Taylor—10th euspen, Delft, June 1–3, 2010
NIF is by far the largest and most complex optical system ever builtNIF i th l i ti fNIF is the culmination of
40 years of laser fusion R&D at LLNL
John S. Taylor—10th EUSPEN, Delft, June 1–3, 2010 5John S. Taylor—10th euspen, Delft, June 1–3, 2010 John S. Taylor—10th euspen, Delft, June 1–3, 2010
Target Chamber Dedication June 1999Target ChamberTarget Chamber Dedication June 1999Target ChamberDedicationJune 1999
John S. Taylor—10th euspen, Delft, June 1–3, 2010 6John S. Taylor—10th euspen, Delft, June 1–3, 2010
NIF laser operationally qualified to 1MJ on March 10, 2000920009
John S. Taylor—10th euspen, Delft, June 1–3, 2010 7John S. Taylor—10th euspen, Delft, June 1–3, 2010
8John S. Taylor—10th euspen, Delft, June 1–3, 2010
Our ignition “point design”
9
Our ignition point design is based on indirect drive
John S. Taylor—10th euspen, Delft, June 1–3, 2010
Capsule implosions in cryogenic gas-filled hohlraums have shown good symmetry at 270 eVhohlraums have shown good symmetry at 270 eV
John S. Taylor—10th euspen, Delft, June 1–3, 2010 10John S. Taylor—10th euspen, Delft, June 1–3, 2010
Capsule implosions in cryogenic gas-filled hohlraums have shown good symmetry at 270 eVhohlraums have shown good symmetry at 270 eV
Precision Engineering is enabling landmark experiments…
… by enhancing determinism in laser performance diagnostics alignment andperformance, diagnostics, alignment, and
target fabrication
11John S. Taylor—10th euspen, Delft, June 1–3, 2010
In this very brief talk, we’ll discuss how precision engineering impacts 4 key areas of NIFengineering impacts 4 key areas of NIF
Di d t i f KDP t l• Diamond turning of KDP crystals
• Mitigation of laser damage on optics Mitigation of laser damage on optics
• Alignment of lasers, targets, diagnostics
• Target fabrication
12John S. Taylor—10th euspen, Delft, June 1–3, 2010
The Final Optics Assembly (FOA) combines a number of critical functions into a single compact packageof critical functions into a single compact package
KDP frequency q yconversion
crystals
John S. Taylor—10th euspen, Delft, June 1–3, 2010
KDP Semi Finishing Machine – Vertical Axis Fly-cutterKDP Semi Finishing Machine Vertical Axis Fly cutter
• KDP Optics are used for laser frequency conversionDiamond Fly-cutting to obtain
the required crystal angle • NIF operates by first doubling and then tripling• Crystal growth axis determines frequency
Tip and tilt platformKDP crystal in mounting fixture14John S. Taylor—10th euspen, Delft, June 1–3, 2010
Final figure and finish are achieved on theare achieved on the “Finishing Machine”
(CAD model)
Workslide motions sensitive direction:Straightness (horizontal) < 100nm/500mmRepeatability < 50nm
Fly-cutter (@ 1000rpm)Fly cutter (@ 1000rpm)Asynchronous error motion < 12nm Thermal growth < 10nm/hr
Fly-cutter carriage motion
1515
Fly cutter carriage motionSlide Pitch < 0.5 arcsecSlide Yaw < 0.2 arcsec
John S. Taylor—10th euspen, Delft, June 1–3, 2010
KDP Finishing Machine during the buildKDP Finishing Machine during the build
Granite base on air isolators
Ai b i i dl
X-axis way installation
Air bearing spindle Spindle integration
Completed system
16John S. Taylor—10th euspen, Delft, June 1–3, 2010
KDP Finishing Machine installed at vendor’sinstalled at vendor’s
facility
1717John S. Taylor—10th euspen, Delft, June 1–3, 2010
Figure and finish achieved by the final finishing machine meet NIF specificationsfinishing machine meet NIF specifications
Surface Finish Transmitted Wavefront
0.8 mm
0.01 – 0.12 mm band 0.8 nm rms
0 12 2 5 b d 1 0
0.31 nm p-v waves @ 633 nm
40 cm
John S. Taylor—10th euspen, Delft, June 1–3, 2010 18
0.12 – 2.5 mm band 1.0 nm rms
KDP frequency conversion crystals are about 1 cm thick with a 40 cm square aperturethick with a 40 cm square aperture
Laser-initiated Surface Damage
19John S. Taylor—10th euspen, Delft, June 1–3, 2010
The KDP crystal is positioned above the milling spindle and machining stagesspindle and machining stages
KDPCrystal
Milling at damage
sitesite R-θ-Z
CL
20John S. Taylor—10th euspen, Delft, June 1–3, 2010
Photo of mitigation development systemPhoto of mitigation development system
21John S. Taylor—10th euspen, Delft, June 1–3, 2010
Full-scale KDP mitigation toolFull-scale KDP mitigation tool
22John S. Taylor—10th euspen, Delft, June 1–3, 2010
Example of KDP damage site mitigated by diamond milling operationmilling operation
After MitigationBefore Mitigation After MitigationBefore Mitigation
Contoured Conical SurfaceLaser-initiated Surface Damage
23John S. Taylor—10th euspen, Delft, June 1–3, 2010
Miti ti dMitigating damage on fused silica wedged focus lenses uses a
CO2 laserCO2 laser
2424John S. Taylor—10th euspen, Delft, June 1–3, 2010
We have engineered machines and facilities to perform production mitigation on NIF opticsperform production mitigation on NIF optics
25John S. Taylor—10th euspen, Delft, June 1–3, 2010
J. Folta
A collimated CO2 laser beam is used to mitigate small damage sites on large optics instead of refinishing themdamage sites on large optics instead of refinishing them
Before mitigationBefore mitigation
After mitigationAfter mitigation
8080 µm
26John S. Taylor—10th euspen, Delft, June 1–3, 2010
J. Folta
A focused CO2 laser can be used to ablate conical pits to mitigate damage sites as large as 500 µm
Before mitigationBefore mitigation
pits to mitigate damage sites as large as 500 µm
Before mitigationBefore mitigation
After mitigationAfter mitigation500 um
Rapid scanning of tightlyRapid scanning of tightly--focused focused highhigh--power COpower CO22 laser pulses to laser pulses to
flfl
2 mm
remove flawsremove flaws
• Precise shape control• Fairly wide process margin
27
• Scalable• Damage robust
John S. Taylor—10th euspen, Delft, June 1–3, 2010
J. Folta
How do we go about aligning 192 laser beams, the target and diagnostics?the target and diagnostics?
John S. Taylor—10th euspen, Delft, June 1–3, 2010 2828John S. Taylor—10th euspen, Delft, June 1–3, 2010
Target Alignment Sensor (TAS)Target Alignment Sensor (TAS)
Target
Focus reference for each of 192 laser beams
TargetAlignment
Sensor( S)
Identify location of datums on target
(TAS)Provide siting datum fordiagnostic systemsg y
TAS links the coordinates of the key elements of a NIF experiment
29John S. Taylor—10th euspen, Delft, June 1–3, 2010
192 beams are aligned to the upper and lower cameras with an automated toolcameras with an automated tool
Beams are aligned to a setpoint on the upper and lower CCDs
Reflected laser alignment beams
CCDCCDTarget Alignment Sensor (TAS) g
are aligned on cameras
CCDCCD
TAS is supported at Target Chamber Center
30John S. Taylor—10th euspen, Delft, June 1–3, 2010
CCDCCD
Target is aligned to a setpoint on the upper and lower CCD camerasand lower CCD cameras
Platens open to focus and align target. • Upper and lower cameras set four degrees of freedom• Two side camera set target height
Top and bottom of target is imaged through a lensthrough a lens
The key is that the laser foci and t t i t d t th
31John S. Taylor—10th euspen, Delft, June 1–3, 2010
target are registered onto the same set of pixel coordinates
• Target alignment sensor has been successfully deployed on NIF shotsdeployed on NIF shots over one year— TAS is an intermediary
between beams and targets
— Calibrated accuracy of TAS is the central component of beam-to-target error budget
— Requalification is expensive so stability is important
32John S. Taylor—10th euspen, Delft, June 1–3, 2010
Alignment performanceg
T NIF di i i (1 l i i ’ )Target to NIF coordinate origin (1 mm zonal position req’t): 300 µm deviation at last survey300 µm deviation at last survey
Target-to-chamber shot-to-shot position repeatability:Target-to-chamber shot-to-shot position repeatability: <100 µm<100 µm
Position of 96 beam centroid at hohlraum: <25 µm <25 µm
Beam pointing to target (1-σ of 96 beams): 64 µm 64 µm rmsrms
Diagnostic line of sight alignment (2-σ): <500 µm<500 µm<500 µm<500 µm
33John S. Taylor—10th euspen, Delft, June 1–3, 2010
Fabricating and measuring targets is a fertile area for exercising precision engineering conceptsexercising precision engineering concepts
Capsule, HohlraumThermal-Mechanical
Package
~10 mmFull NIF cryo target
attached to base
Package
~10 mm
~200 mm
Component tolerances: 1-3 mAssembly tolerances: 1-20 m Dynamic Range: 1:104
34
Assembly tolerances: 1-20 mBond gap tolerances: 0.25 m
Dynamic Range: 1:10
John S. Taylor—10th euspen, Delft, June 1–3, 2010
Fabricating and measuring targets is a fertile area for exercising precision engineering conceptsexercising precision engineering concepts
Capsule, HohlraumThermal-Mechanical
PackageTh d i f 1 10Th d i f 1 1044 i h ll ii h ll i
~10 mmFull NIF cryo target
attached to base
PackageThe dynamic range of 1:10The dynamic range of 1:1044 is challenging:is challenging:
Agility Agility required for new target types, target design required for new target types, target design modifications and component variancesmodifications and component variances~10 mm modifications, and component variancesmodifications, and component variances
Human interface Human interface for integrating motion control, force, visiblefor integrating motion control, force, visible--light microscopy, bondinglight microscopy, bonding
Production rateProduction rate greater than prototyping, less than HVMgreater than prototyping, less than HVM
SizeSize precludes use of many traditional toolsprecludes use of many traditional tools~200 mmSize Size precludes use of many traditional tools precludes use of many traditional tools (indicators, fasteners, etc)(indicators, fasteners, etc)
Component tolerances: 1-3 mAssembly tolerances: 1-20 m Dynamic Range: 1:104
John S. Taylor—10th euspen, Delft, June 1–3, 2010 35
Assembly tolerances: 1-20 mBond gap tolerances: ~0.25 m
Dynamic Range: 1:10
Examples of Precision Engineering conceptsin target fabricationin target fabrication
Precision ConceptPrecision Concept ExampleExample
• Rigorous tolerance analysis Hohlraum length – Monte Carlo analysis– Monte Carlo analysis
• Controlled degrees of freedom Final Assembly Machine• Precision with agility Flex FAM• Precision with agility Flex-FAM
Rick Montesanti willRick Montesanti will discuss precision assembly in his talk
C Castro
• Design for measurability Base metrology features
C. Castro
36John S. Taylor—10th euspen, Delft, June 1–3, 2010
Design for MeasurabilityDesign for Measurability
How to relate the base-gripperBase
CoordinateSystemHow to relate the base-gripper
coordinate system to the Hohlraum coordinate system?
System
• Contact planes defineHohlraum
CoordinateSystem
• Contact planes define normal axis
• Pins define centering
But reference features are not easily observed in a coordinate measuring machine
37
machine
John S. Taylor—10th euspen, Delft, June 1–3, 2010
The design of metrology features onto the base enabled datums to be defined to register the Hohlraumenabled datums to be defined to register the Hohlraum
Edges are visible in Edges are visible in Planes can bePlanes can be ggCMM to define CMM to define x,yx,y axes & yawaxes & yaw
Planes can be Planes can be trammedtrammed to define to define
pitch & rollpitch & roll
Datum plane contacting
PlanesPlanes andand Edges Edges define a define a coordcoord g
Gripper
Centering
system for system for registering the registering the
Hohlraum Hohlraum Centering Pin(s)
Small changes in the visibility of planes and edges greatly improves
38
measurability
John S. Taylor—10th euspen, Delft, June 1–3, 2010E. Alger, S. Edson
John S. Taylor—10th EUSPEN, Delft, June 1–3, 2010 39John S. Taylor—10th euspen, Delft, June 1–3, 2010
The long-sought goal of achieving fusion ignition and burn is close to realization
The long-sought goal of achieving fusion ignition and burn is close to realizationignition and burn is close to realizationignition and burn is close to realization
John S. Taylor—10th EUSPEN, Delft, June 1–3, 2010 40John S. Taylor—10th euspen, Delft, June 1–3, 2010
41John S. Taylor—10th euspen, Delft, June 1–3, 2010