Vacuum UV Spectroscopy

Aberration Corrected Plane Holographic Gratings

Specifications and Control

- Ultimate Specification Standard Specification Control
Dimension Up to 250 mm length - -
Radius of Curvature Superior at few tens of km LTP Measurements  
Slope error Down to 0.1 arcsec rms 0.2 arcsec rms LTP measurement Interferometer
Microroughness Down to 2 Å rms 5 Å rms Micromap measurements
Substrate Silicon Zerodur Fused Silica SiC CVD - -
Coating Au Pt AlMgF Ni Cr binding layer Quartz monitoring
Groove Density Optimised with JY proprietary software Moiré Fringes (JY patent) Optical control using recording layout (JY patent)  
Efficiency Groove depth and duty cycle ratio optimised with JY proprietary software    
Groove Depth +/- 5% +/- 10% AFM measurements
c/d Ratio +/- 5% +/- 10% AFM measurements

Examples of Aberration Corrected Plane Holographic Gratings

Size mm Optical surface mm Radiuses of Curvature Slope Error arcsec rms Max Microroughness Å rms Coating Substrate
200x50x30 190x45 JY calibrated samples 0.2 arcsec rms 5 Au or Pt Silicon Zerodur Fused Silica
150x40x25 140x35 JY calibrated samples 0.2 arcsec rms 5 Au or Pt Silicon Zerodur Fused Silica
100x30x20 90x25 JY calibrated samples 0.1 arcsec rms 5 Au or Pt Silicon Zerodur Fused Silica

Note: Groove density is obtained by interference of two spherical wavefronts