Excimer Cavity Rear Mirrors (XRM)

- Rear mirrors (intra-cavity) for ArF (193nm), KrF (248nm),
- or XeCl (308nm) excimer lasers
- Calcium Fluoride or Magnesium Fluoride substrates
There are 193nm, 248nm, and 308nm excimer lasers. These wavelengths are found in applications such as micro-lithography, micro-manufacturing, and medical devices. At these wavelengths, it is recommended to use Calcium Fluoride or Magnesium Fluoride substrates for intra-cavity transmissive optical elements. Rear cavity mirrors provide at least 99.5% reflectance at the laser wavelength. Note that Lambda’s high quality excimer laser cavity coatings are designed for Acid/Fluorine resistance.
Material: |
UV grade MgF₂
UV grade CaF₂ |
Surface Quality: |
< 20 / 10 |
Surface Flatness: |
< λ / 10 @ 633 nm |
Diameter Tolerance: |
< + 0.00 / – 0.20 mm |
Thickness Tolerance: |
< ± 0.25 mm |
Clear Aperture: |
> 85% of diameter |
Damage Threshold: |
>1.2 J /cm², 10 ns |
Durability: |
Meet adhesion and abrasion per MIL-C-675 |
Excimer Cavity Rear Mirrors (XRM)