Optical Coatings

Laser-Line MAX-R Coatings
These multilayer coatings achieve the highest possible reflectances
at specific laser wavelengths and at particular angles of incidence. At
these wavelengths and angles, laser-line MAX-R coatings outperform
MAXBRIte . We offer coatings for angles of incidence at
0 degrees (see figure 5.48) and 45 degrees (see figure 5.49). Because
the layer thicknesses differ for these two angles, the coatings cannot
be used interchangeably. Laser-line MAX-R coatings are intended
for external beam-manipulation applications. Specified coating
reflectances apply to p-polarization (except at normal incidence,
where the p- and s-polarization states are indistinguishable).
Reflectances for s-polarization generally exceed those for p-
polarization. Other coatings can be supplied at any center wavelength
from 193 nm to 1.6 mm.
APPLICATION NOTE
LASER-INDUCED DAMAGE
The following laser damage threshold statistics do
not constitute a performance guarantee but should
be representative for MAX-R coatings.
/205 2.4 J/cm 2 810%,
10-nsec pulse (195 MW/cm 2 ) at 355 nm
/255 13.3 J/cm 2 810%,
12-nsec pulse (920 MW/cm 2 ) at 355 nm
/225 12.6 J/cm 2 810%,
10-nsec pulse (1008 MW/cm 2 ) at 532 nm
/275 13.6 J/cm 2 810%,
10-nsec pulse (1088 MW/cm 2 ) at 532 nm
/241 2.4 J/cm 2 810%,
20-nsec pulse (700 MW/cm 2 ) at 1064 nm
/291 17.7 J/cm 2 810%,
20-nsec pulse (800 MW/cm 2 ) at 1064 nm
PERCENT REFLECTANCE
100
80
60
40
20
Figure 5.48
PERCENT REFLECTANCE
100
Figure 5.49
normal incidence
typical reflectance curve
0.8 0.9 1.0 1.1 1.2
RELATIVE WAVELENGTH, g = l 0 /l
80
60
40
20
MAX-R coating, normal incidence
45° incidence
s-polarization
p-polarization
typical reflectance curves
0.8 0.9 1.0 1.1 1.2
RELATIVE WAVELENGTH, g = l 0 /l
MAX-R coating, 45-degree incidence
$ Highest possible reflectance achieved at specific laser
wavelengths and angles of incidence
$ Standard MAX-R coatings available for popular
laser wavelengths at both 0 degrees and 45 degrees
$ Custom designs easily produced
$ Coatings available from 193 nm to 1550 nm
PLEASE NOTE FOR THE ABOVE CURVES:
For g = l 0 /l, l 0 is the design wavelength and l is
arbitrary. For example, l = l 0 /g = 1064 nm/0.9 =
1182 nm, if one looks at g = 0.9 for the /291 coating.
For values of g below 0.8 and above 1.2, the
reflectance curves oscillate sinusoidally, in a manner
that varies from coating to coating and run to run.
Fundamental Optics Gaussian Beam Optics Optical Specifications Material Properties Optical Coatings
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