| Ultimate Specifications |
Standard Specifications |
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
Measurements Interferometer |
| Microroughness |
Down
to 2 Å rms |
5 Å rms |
Micromap
measurements |
| Substrate |
Silicon Fused Silica SiC CVD |
||
| Coating |
Au Pt AlMgF Ni |
Cr
binding layer |
Quartz
monitoring |
| Groove Density |
Follows
a polynomial law Recording layout using JY proprietry software Optical ray tracing of the monochromator |
Moiré Fringes
(JY patent) LTP measurement |
|
| Efficiency |
Groove
depth and duty cycle ratio optimised with JY proprietry
software |
||
| Groove Depth |
+/-
5% |
+/-
10% |
AFM
measurements |
| c/d Ratio |
+/-
5% |
+/-
10% |
AFM
measurements |
Examples of Variable Line Space Plane Holographic Gratings
| Size mm |
Optical surface mm |
Slope Error arcsec rms |
Max Microroughness Å rms |
Coating |
Substrate |
| 200x50x30 |
190x45 |
0.2
arcsec rms |
5 |
Au
or Pt |
Silicon Fused Silica |
| 150x40x25 |
140x35 |
0.2
arcsec rms |
5 |
Au
or Pt |
Silicon Fused Silica |
| 100x30x20 |
90x25 |
0.1
arcsec rms |
5 |
Au
or Pt |
Silicon Fused Silica |
Note: Recording wavefronts are either two spherical, one spherical and one aspherical or both aspherical depending on the required polynomial.
