VIRGO Mode Cleaner Concave Mirror Characterization Reference : C03004 + C03006

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VIRGO Mode Cleaner

Concave Mirror Characterization Reference : C03004 + C03006

VIR-SPE-LYO-4340-0024

Issue :1

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Concave Mode Cleaner Mirror Substrate Drawings

Signification of the ARROW etched on the edge of the substrate:

• It shows SIDE B Side A

Flat

Side B Concave

Arrow

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Serial Number: C03004 + C03006

VIRGO Requirements

SMA-VIRGO Measurements

Outside Diameter (mm) 80 +/- 0,5 80,0 +/- 0,1

Thickness (mm) 30 +/- 0,5 31,3 +/- 0,1

Side A x

Antireflective Coating @1064 nm Mirror @633 nm (R=70 %)

∅

∅75 mm Coating

Nature

Side B x High Reflectivity Coating

∅∅∅

∅75 mm

Side A x 8,3 nm ∅∅∅∅60 mm

5 nm ∅∅∅22 mm∅ Flatness

R.M.S.

Side B ≤≤≤≤ 25 nm ∅∅∅∅60 mm

≤≤≤≤ 2,5 nm ∅∅∅∅22 mm

8,8 nm ∅∅∅∅60 mm 3,4 nm ∅∅∅∅22 mm

Radius of Curvature (m)

Side B -178 < R < -187 m -180,7 +/- 2 m ∅∅∅∅60 mm -181,6 +/- 2 m ∅∅∅∅22 mm

Average Scattering (3° incidence)

Side B

< 50 ppm 65 ppm ∅∅∅ 60mm∅ 38 ppm ∅∅∅ 22mm∅

Absorption HR

Side B < 5 ppm 1,2 ppm

(center) Transmission

(1° incidence) T < 50 ppm 5,7 ppm ∅∅∅∅ 60mm

Comments:

• The scattering value comes from the poor quality of the substrate surface before coating (high roughness, some large defects).

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Wavefront Side B (∅∅∅∅60 mm)

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Transmission in ppm (∅∅∅∅60 mm)

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Average Scattering Side B (∅∅∅∅60 mm)

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Transmission Spectrum

0 10 20 30 40 50 60 70 80 90 100

400 600 800 1000 1200 1400 1600

Wavelength (nm)

Transmission (%)

R = 69% @ 633 nm