Broadband mirrors

Applications of broadband mirrors

• Laser systems where one optical element must reflect two or more wavelengths;
• Scientific experiments;
• As universal mirror to substitute several laser line (narrowband) mirrors.

Material

Substrates used for 3photon standard broadband mirrors (BBHR) are made of ultra-violet grade fused silica (UVFS, usually Corning 7980) material. This material has perfect properties to allow engineers to polish it smoothly to 10-5 Scratch-Dig. During the polishing reflected wave-front distortion (irregularity, flatness) values of <λ/10 @ 632.8 nm are usually reached. For precise and ultra-violet (UV) applications even better quality can be manufactured. 3photon also provide other materials such as Schott N-BK7, germanium, calcium fluoride, laser crystals and other materials.

Shape, size and curvature

Standard 3photon broadband mirrors (BBHR) are round either Ø25.4 mm or Ø12.7 mm in diameter and 6 mm or 3 mm thickness.

Nevertheless, complex figures, e.g. spherical, cylindrical convex or concave, aspherical are also available upon request.

3photon engineers are experienced to work with various sizes from micro-optics to large optics of  up to 400 mm in diameter.

Reflection value

Depending on your wavelength range, the reflection values may vary. 3photon can offer:

• Standard reflection of >99.8 % at 0° angle of incidence, using electron beam evaporation (EBE) or ion assisted deposition (IAD) technologies;
• High reflection >99.99% employing ion beam sputtering (IBS) technology;
• Please note, that the broader the range is, the more difficult is to ensure high reflection values.

Spectral range

3photon optical coating engineers can design broad band mirrors starting from ultra-violet (UV) 193 nm to visible light ranges 400-700 nm to near and far infrared, in some cases up to 6 µm.

Angle of incidence

Broad band mirrors can also be manufactured to perform well in different angle of incidence ranges 0-22°; 0-45°, 54-56°, 0-7° or optimized for single angle of incidence e.g. normal angle of incidence (0°), 22.5°, 45°, 56°, or others.