The 18E20DM.6 Laser Line Dielectric Elliptical Mirror is a highly efficient reflector optimized for the 441.6 nm wavelength. This 1.30 inch (33.02 mm) minor axis, 1.838 inch (46.70 mm) major axis, eliptical mirror is made from a 9.37 mm thick Borofloat® 33 substrate. Borofloat has low thermal expansion and is an excellent substrate for most applications. The DM.6 coating is designed for use with HeCd lasers and has a center wavelength of 441.6 nm. The coating achieves greater than 99% reflectance, from 0–45° angle of incidence, for any polarization. This multilayer dielectric coating is extremely durable, making it resistant to damage from repeated cleaning. This mirror has a λ/10 surface flatness and a 15-5 surface quality.
| Model | 18E20DM.6 |
|---|---|
| Mirror Shape | Elliptical |
| Wavelength Range | 441.6 nm |
| Dimensions | 2.6 x 1.8 in. (66.0 x 46.7 mm) |
| Thickness | 0.49 in. (12.5 mm) |
| Material | Borofloat 33 or equivalent |
| Coating Type | Laser Line Dielectric |
| Surface Quality | 15-5 scratch-dig |
| Coating Code | DM.6 |
| Clear Aperture | ≥central 80% of diameter |
| Reflectivity | Rs, Rp>99% @ 441.6 nm |
| Angle of Incidence | 0-45° |
| Surface Flatness | λ/10 |
| Chamfers | 0.38–1.14 mm face width |
| Chamfers Angle/Tolerance | 45° ±15° |
| Thickness Tolerance | ±0.25 mm |
| S2 Surface | Ground |
| Major Axis | 2.600 in. |
| Minor Axes | 1.838 in. |
| Cleaning | Non-abrasive method, acetone or isopropyl alcohol on lens tissue recommended |
