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Spectralon® Optical-Grade Reflectance Material


  • >99% Diffuse Reflectance
  • Extremely Lambertian
  • Chemically Inert
  • Thermally Stable
  • Environmentally Stable
  • NIST Traceable Calibration


  • Optical Components
  • Densitometer Standards
  • Remote Sensing Targets

Labsphere's Spectralon® Reflectance Material can be machined into a wide variety of shapes for the construction of optical components. The material has hardness roughly equal to that of high-density polyethylene and is thermally stable to >400°C.

Spectralon® Reflectance Material gives the highest diffuse reflectance of any known material or coating over the UV-VIS-NIR region of the spectrum.

In-house machining allows samples to be created quickly and easily, and modified throughout the design, prototyping and testing process. This manufacturing flexibility means low or high volume quantities can be ordered. Labsphere's engineering staff has an established industry-wide reputation for its knowledge and experience in laser pump chamber design and often collaborates with customers to develop custom Spectralon® designs.

The surface and immediate subsurface of Labsphere's Spectralon® exhibits highly Lambertian behavior. The porous network produces multiple reflections in the first few tenths of a millimeter of Spectralon®.

The use of Labsphere's Spectralon® should be limited to the UV-VIS-NIR. Spectralon® exhibits absorbencies at 2800 nm, then absorbs strongly (>20% reflectance) from 5.4 to 8 μm.

Spectralon® exhibits relatively flat spectral distribution over most of the UV-VIS-NIR from 250 to 2000 nm. These spectral properties exceed those of most paints, which show strong absorbencies in the UV due to absorbencies by TiO2 or similar pigments. The hydrophobic nature of Spectralon® also leads to exclusion of water overtone bands in the NIR, which may occur in barium-sulfate-based materials. The open structure of Spectralon® causes both reflectance and transmittance, but not absorbance of light.


Thermal Stability: Decomposes at > 400OC
Laser Damage Threshold: 4 Joule/cm2

Physical, Thermo-Optical and Electronic Properties of Spectralon

Value Test Method  
Substance: n/a Polytetrafluoroethylene
Vacuum Compatibility: n/a to 10-6 Torr
Flammability: n/a Non flammable (UL rating V-O)
Water Permeability: ASTM D-570 <0.001% Hydrophobic
Volume Resistivity: IEC 60093 >1018 ohm/cm
Dielectric Strength: ASTM D-149

18 V/μm

Yield Stress: ASTM D638

208 psi

Ultimate Stress: ASTM D638

891 psi

Absorbance: (as) n/a 0.07
Emittance: (e) n/a



Download A Datasheet for Optical-Grade Spectralon

Download Spectralon Design Guidelines

Technical Library

Download A Guide To Reflectance Materials and Coatings

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