Plane parallels, etalons

Stock substrates

Plane-parallels, wedge < 10’’

Diameter
Ø mm
Thickness
t mm
Wedge
Parallelism
Flatness
λ (633 nm)
Surface
imp.tol.
UV-FS
Article-No.
price
in €
25 6.35 <10″ λ/10 5/3 x 0.040 S-01015 90
50 9.5 <10″ λ/10 5/3 x 0.040 S-01016 160

All components with an € price are available from stock.

Etalons, wedge < 0.2’’

Fabry-Perot etalons are extremely narrow line width filters with a series of sharp transmission peaks, separated by the free spectral range (FSR). FSR depends only on the optical thickness of the etalons, whereas the finesse (F) is determined not only by the reflectivity of the coatings, but mainly by surface quality, parallelism, homogeneity of the substrate material and defect-free coatings. Solid etalons can be tuned by tilting and by temperature change.

If a minimum resolvable resolution Δλ is nee­ded, the reflectivity finesse FR can be calcula­ted with



The final finesse of the etalon is in most cases limited by the flatness finesse FF (flatness of λ/20 gives FF = 20) for beam diameter 20 mm. With thinner beams FF can grow to > 200. Pairs of etalons in series may be used to obtain ultra high resolution combined with a very long FSR. The resulting finesse of such a combination can be one order of magnitude higher.

Besides lower costs, solid etalons offer the following advantages over air spaced etalons for intracavity use:
higher transmission
 lower size
 harder coatings with
 higher damage threshold

Diam.
Ø mm
Thickn.
t mm
Wedge
Parallelism
Flatness in T
λ (633 nm)
Surface
imp.tol.
Suprasil 311
Article-No.
price
in €
FSR
nm @ 633 nm
FSR
GHz
25 0.1 <0.2″ λ/20 5/3 x 0.040 S-00209 210 1.38 1000
25 0.2 <0.2″ λ/20 5/3 x 0.040 S-00185 200 0.69 500
25 0.3 <0.2″ λ/20 5/3 x 0.040 S-00740 200 0.46 330
25 0.5 <0.2″ λ/20 5/3 x 0.040 S-00353 190 0.28 200
25 1 <0.2″ λ/20 5/3 x 0.040 S-01001 180 0.14 100
25 2 <0.2″ λ/20 5/3 x 0.040 S-00932 170 0.069 50
25 3 <0.2″ λ/20 5/3 x 0.040 S-00933 170 0.046 33
25 4 <0.2″ λ/20 5/3 x 0.040 S-00029 170 0.034 25
25 5 <0.2″ λ/20 5/3 x 0.040 S-00206 180 0.028 20
25 6.35 <0.2″ λ/20 5/3 x 0.040 S-00934 190 0.022 16
25 10 <0.2″ λ/20 5/3 x 0.040 S-00754 200 0.014 10
25 20 <0.2″ λ/20 5/3 x 0.040 S-00495 300 0.007 5

All components with an € price are available from stock.