Proposal for a Universal Test Mirror for Characterization of SlopeMeasuring Instruments

Conference · Tue Jul 31 04:00:00 EDT 2007

OSTI ID:932789

Yashchuk, Valeriy V; McKinney, Wayne R; Warwick, Tony; Noll, Tino; Siewert, Frank; Zeschke, Thomas; Geckeler, Ralf D

The development of third generation light sources like theAdvanced Light Source (ALS) or BESSY II brought to a focus the need forhigh performance synchrotron optics with unprecedented tolerances forslope error and micro roughness. Proposed beam lines at Free ElectronLasers (FEL) require optical elements up to a length of one meter,characterized by a residual slope error in the range of 0.1murad (rms),and rms values of 0.1 nm for micro roughness. These optical elements mustbe inspected by highly accurate measuring instruments, providing ameasurement uncertainty lower than the specified accuracy of the surfaceunder test. It is essential that metrology devices in use at synchrotronlaboratories be precisely characterized and calibrated to achieve thistarget. In this paper we discuss a proposal for a Universal Test Mirror(UTM) as a realization of a high performance calibration instrument. Theinstrument would provide an ideal calibration surface to replicate aredundant surface under test of redundant figure. The application of asophisticated calibration instrument will allow the elimination of themajority of the systematic error from the error budget of an individualmeasurement of a particular optical element. We present the limitationsof existing methods, initial UTM design considerations, possiblecalibration algorithms, and an estimation of the expectedaccuracy.

• Research Organization: Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US); Advanced Light Source(ALS)
• Sponsoring Organization: USDOE Director. Office of Science. Basic EnergySciences
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 932789
• Report Number(s): LBNL--62509; BnR: KC0204016
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
47 OTHER INSTRUMENTATION
ACCURACY
ADVANCED LIGHT SOURCE
ALGORITHMS
CALIBRATION
DESIGN
FREE ELECTRON LASERS
LIGHT SOURCES
MEASURING INSTRUMENTS
MIRRORS
OPTICS
PERFORMANCE
ROUGHNESS
SYNCHROTRONS
slope measuring instrument long trace profiler LTP calibrationsystematic error reduction test mirror