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High Precision Single Crystal Germanium Windows With AR And DLC Coatings

Basic Information
Place of Origin: Wuhan,China
Brand Name: Wuhan Siwer Optics
Minimum Order Quantity: 5 pieces
Price: 25-98USD/piece
Packaging Details: 1.Tissue paper. 2.Plastic foam packaging film. 3.Hard carton box with quakeproof filler
Delivery Time: 3-4 weeks
Payment Terms: T/T, Western Union
Supply Ability: 3000 pieces/month
Detail Information
Material: Single Crystal Germanium Size Tolerance: +/-0.1mm
Chamfer: 0.2-0.5mm Surface Quality: 40/20
Surface Flatness: Lambda/4 In 25.4mm Parallelism: 0.01mm
Standard Coating: AR/AR@8-14um Size Range: 5-300mm
Usage: Infared System
High Light:

optical window

,

infrared system protectd window


Product Description

Infrared Germanium window

The transmittance range of the optical germanium material is 2-14 um, and the refractive index is as high as 4. Germanium lens and germanium window are widely used in thermal imaging system.
Germanium window is a common protective window in infrared imaging system. Its material quality, surface smoothness, parallelism, surface quality and coating quality will directly affect the imaging effect.
The resistivity of optical grade single crystal germanium material we choose is usually 5-40 Ohms. If the customer requests, we can also choose germanium material with specified resistivity.
Due to the high refractive index and high surface reflectivity of germanium (r > 30%), optical germanium windows usually need AR coating on its surface.
If the equipment is used in a bad environment, the outer side of the germanium protection window needs to be coated with DLC Coating.DLC Coating has excellent wear resistance, acid resistance and corrosion resistance.
 


Optical Properties of Germanium Window

MaterialSingle Crystal Germanium
AR Coating Range3-5um,8-12um,3-11um
Reflectance over
AR Coating Range @ 0° AOI

Ravg < 2%,3-5um or 8-12um

Ravg<5%,3-11um

Transmission over
AR Coating Range @ 0° AOI
Tavg > 94%,3-5um or 8-12um
Diameter Tolerance+0.0/-0.1 mm
Thickness Tolerance±0.1 mm
Parallelism3 arc min
Surface Quality60-40 Scratch-Dig
Surface Flatness
(Plano Side)
λ/2 at 633nm
Surface Irregularity
(Peak to Valley)
λ/2 at 633nm
Clear Aperture>Ø10.16 mm (Ø1/2" Lenses)
>Ø20.32 mm (Ø1" Lenses)
Design Wavelength10.6 μm

 
 


Transmittance of Antireflection coatings:

High Precision Single Crystal Germanium Windows With AR And DLC Coatings 0High Precision Single Crystal Germanium Windows With AR And DLC Coatings 1

High Precision Single Crystal Germanium Windows With AR And DLC Coatings 2High Precision Single Crystal Germanium Windows With AR And DLC Coatings 3


Germanium properties:

Chemical FormulaGe
Crystal FormPoly or Single Crystal
Crystal ClassCubic
Resistivity, Ohm*cm0.01-40
Lattice Constant, Å5.66
Molecular Weight72.6
Density, g/cm3 at 300 K5.33
Dielectric Constant for 9.37 x 109 Hz at 300 K16.6
Melting Temperature, K1210
Thermal Conductivity, W/(m K) at 293 K59
Thermal Expansion, 1/K at 298 K6.1 x 10-6
Specific Heat, cal/(g K) at 273-373 K0.074
Debye Temperature, K370
Bandgap, eV0.67
Solubility in waterNone
Knoop Hardness, kg/mm2800
Mohs Hardness6.3
Young's Modulus, GPa102.66
Shear Modulus, GPa67.04
Bulk Modulus, GPa77.86
Poisson's Ratio0.278

 

 


Infrared Elements Selection Guide

High Precision Single Crystal Germanium Windows With AR And DLC Coatings 4

Production process

High Precision Single Crystal Germanium Windows With AR And DLC Coatings 5
 

Contact Details
Jason