29 Apr 2012 Selecting the proper mirror for your application requires making a number of choices. A few of the many considerations include: Reflectivity, Laser Damage Resistance, Coating Durability, Thermal Expansion of the substrate, Wavefront Distortion, Scattered Light, and certainly Cost.
Mirror type in Rising EO:
● Dielectric Mirrors● Protected Aluminum● UV Enhanced Aluminum ● Protectied Silver● Protected Gold
Metallic Mirrorsrepresent a good mixture of performance and value. These broadband coatings are relatively insensitive to wavelength, angle of incidence, and polarization. However high-energy levels should be avoided.Protected Aluminum--For general broadband use, a protected aluminum coating offers the best option. A SiO2 coating is used to protect the delicate aluminum coating, making it suitable for laboratory and industrial use. This coating gives a reflectivity that most closely matches the reflection of a bare aluminum coating: Ravg>87% @400-1200nm.UV Enhanced Aluminum-- Aluminum coated mirrors are cost effective and offered in a variety of sizes. Bare aluminum is extremely delicate and susceptible to damage. A protective overcoat is layered over the aluminum to make it damage resistant. Our UV Enhanced coating is made by using an overcoat of MgF2 which is transparent in the UV allowing 200-230nm R>65%; 230-250nm R>80%; 251-1200nm R>85% (Ravg>93% @400-1200nm).Protective Silver and Protective Gold also are available upon request! Protected Silver: Ravg>95% @450-12000nm. Gold is the most efficient reflective coating throughout the entire IR range. Gold coatings provide a surface that may be easily cleaned while providing 98% average reflectance throughout the IR region. |
