Error reduction techniques for measuring long synchrotron mirrors

Conference · Wed Jul 01 04:00:00 EDT 1998

OSTI ID:666054

Irick, S

Many instruments and techniques are used for measuring long mirror surfaces. A Fizeau interferometer may be used to measure mirrors much longer than the interferometer aperture size by using grazing incidence at the mirror surface and analyzing the light reflected from a flat end mirror. Advantages of this technique are data acquisition speed and use of a common instrument. Disadvantages are reduced sampling interval, uncertainty of tangential position, and sagittal/tangential aspect ratio other than unity. Also, deep aspheric surfaces cannot be measured on a Fizeau interferometer without a specially made fringe nulling holographic plate. Other scanning instruments have been developed for measuring height, slope, or curvature profiles of the surface, but lack accuracy for very long scans required for X-ray synchrotron mirrors. The Long Trace Profiler (LTP) was developed specifically for long x-ray mirror measurement, and still outperforms other instruments, especially for aspheres. Thus, this paper focuses on error reduction techniques for the LTP.

• Research Organization: Lawrence Berkeley National Lab., Advanced Light Source Div., Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Energy Research, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 666054
• Report Number(s): LBNL--42097; LSBL--479; CONF-980731--; ON: DE98059382
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCELERATOR FACILITIES
CALIBRATION
DATA PROCESSING
ERRORS
MEASURING INSTRUMENTS
MEASURING METHODS
MIRRORS
SYNCHROTRON RADIATION SOURCES
X RADIATION