P505 – PGM SXUV BESSY PTB
Application
Plane grating monochromator (PGM) for soft X-ray synchrotron radiation
Year of delivery
2023
Installation site
SXUV beamline of National Metrology Institute of Germany (PTB) at BESSY HZB, Germany
Design Features
- Plane grating monochromator (PGM).
-
Negative beam offset design (downward deflecting mirror) for high stability when using long optical elements.
- Spectral range: 70 – 2000 eV.
- Optical elements: one plane mirror and two plane gratings.
- Temperature sensors at internal mechanics, mirror and gratings holders.
-
Active water cooling of all optical elements.
- Mechanically decoupled internal mechanics from the vacuum chamber.
- Internal mechanics directly connected to the adjustable support structure underneath.
-
EtherCAT based motion control system, synchronized encoder readout (suitable for on-the-fly measurements), software with server-client architecture, TCP-IP protocol, EPICS interface.
- Adjustable support structure.
- Permanently installed bakeout provisions.
Performance Features
- High positioning resolution.
- High pitch rotation stability and repeatability.
- Minimized mounting induced deformations.
Outer Dimensions
Technical specifications and performance values
General
Vacuum chamber
Chamber type
stadium shaped footprint
Main flanges
at the top
Material
1.4404 (C < 0.02%)
Base pressure
10-10 mbar range
Optical design parameters
Beam height (entrance)
1400 mm
Beam offset
-30 mm
Number of plane mirrors
1
Plane mirror dimensions
704 mm x 95 mm x 70 mm
Number of gratings
2
Gratings dimensions
152 mm x 40 mm x 50 mm
Support structure
Adjustment ranges
Vertical translation
± 10 mm
Lateral translation
± 5 mm
Longitudinal translation
± 5 mm
Tilt
± 1°
Yaw
± 1°
Plane mirror
Pitch rotation
Range
-0.62° to +14.60°
Resolution (design value)
0.0244 µrad /motor fine step
(1/256, recommended)
0.00146 µrad /encoder count
Resolution (measured value)
0.20 µrad
Repeatability
0.22 µrad (pitch)
0.63 µrad (roll)
Long-term stability (1.5 h)
0.028 µrad
Scanning speed
1 °/s
Translation
Range
-30.54 mm to +38.78 mm
Resolution (design value)
0.013 µm /motor fine step
(1/64, recommended)
0.05 µm /encoder count
Repeatability
0.38 µrad (pitch)
0.90 µrad (roll)
< 100 µm (translation)
Scanning speed
1 mm /s
Gratings
Pitch rotation
Range
-0.58° to +20°
Resolution (design value)
0.03125 µrad /motor fine step
(1/256, recommended)
0.00146 µrad /encoder count
Resolution (measured value)
0.20 µrad
Repeatability
0.13 µrad (pitch)
0.26 µrad (roll)
Long-term stability (1.5 h)
0.032 µrad
Scanning speed
1 °/s
Translation (grating exchange)
Range
-48.77 mm to +48.52 mm
Resolution (design value)
0.013 µm /motor fine step
(1/64, recommended)
0.05 µm /encoder count
Repeatability
0.12 µrad (pitch)
0.27 µrad (roll)
< 100 µm (translation)
Scanning speed
1 mm /s
Performance Test Results
Pitch deviation after pitch change (mirror)
Roll deviation after pitch change (mirror)
Pitch deviation after pitch change (grating)
Roll deviation after pitch change (grating)
Pitch deviation after mirror lateral translation
Roll deviation after mirror lateral translation
Pitch deviation after grating lateral translation
Roll deviation after grating lateral translation
Mirror pitch long-term stability
Grating pitch long-term stability
Mirror lateral position long-term stability
Grating lateral position long-term stability
Mirror pitch positioning resolution
Mirror pitch step width
Grating pitch positioning resolution
Grating pitch step width
Residual gas analysis
