wavelengths
 

Low GDD mirrors

Dispersive Coatings

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:

Examples

If not mentioned otherwise, all values and diagrams are given

... for the standard substrate material used in the described wavelength area (mostly Fused Silica or CaF2).

... without consideration of the rear surface.

... with EBE coating technique for a good cost-performance ratio.

Customized coatings are available for all types.

 

–––– dashed lines show the zoomed curve with the stated magnification

HR 1020-1040 nm / 0-10° low GDD
[B-11072]HR 1020-1040 nm / 0-10° low GDD

1020-1040 nm: R > 99.9%; | GDD (R) | < 20 fs² (IBS-coating)

HT 970-982 nm T 7.5% 1035-1055 nm / 0° low GDD
[B-11872]HT 970-982 nm T 7.5% 1035-1055 nm / 0° low GDD

970-982 nm: R < 5%; 1035-1055 nm: R ±1% (IBS-coating)

R 99.5% 990-1090 nm / 0° low GDD
[B-12042]]R 99.5% 990-1090 nm / 0° low GDD

990-1090 nm: T ±0.15%; | GDD (R) | < 10 fs² (IBS-coating)

HR 760-910 nm / 45°p low GDD
[B-12162]]HR 760-910 nm / 45°p low GDD

760-910 nm: Rp > 99.8%; | GDD (Rp) | < 50 fs² (IBS-coating)

Ag enhanced 450-1000 nm
[B-11437]]Ag enhanced 450-1000 nm

450-1000 nm: R > 90%; Ravg > 97%

 
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