Low GDD mirrors
After having managed to produce short laser pulses, it is necessary to propagate these pulses without disturbing the temporal beam profile. This is the moment where low dispersive beam steering mirrors enter the game.
Often metal mirrors like gold or special enhanced silver mirrors are the most economical solution while having low dispersion.
The major drawbacks of these mirrors are limited reflectivity and higher absorption losses, which may cause problems in applications with high average power.
Alternatively dielectric mirrors can be optimized for low GDD. They offer very low losses avoiding thermal problems but normally have a near-zero GDD only for a limited spectral bandwidth. To overcome this, it is possible to make use of the concept of chirped mirror pairs.
All low GDD coatings can be designed on customer request, see examples:
970-982 nm: R < 5%; 1035-1055 nm: R ± 1% (IBS-coating)
990-1090 nm: T ± 0.15%; | GDD (R) | < 10 fs² (IBS-coating)
Every coating type can be optimized
• substrate material
• reflection / transmis-
• angle of incidence
• GDD value
Alternatively we can create
a totally new design for you.