Refractive Index of TiO2 - Amorphous, Titanium Dioxide

Titanium dioxide (TiO2) is well-known for having a very high index of refraction, and this has led to its common use in thin-film optics. Typically, TiO2 is one component of alternating layers of high and low refractive index materials that by the principle of optical interference tailor the thin-film optic's spectral reflectance profile. This technique can be used to make optical filters, reflectors, and antireflection (AR) coatings for eyeglasses and other lenses. It is common to find titanium dioxide paired with silicon dioxide (SiO2) as the low refractive index material.

TiO2's index can vary due to density variations caused by different deposition processes. These conditions can produce different forms of titania (rutile, amorphous, anatase). In its particulate form titanium dioxide is bright white, highly scattering, and ideal for use as a pigment. It is present in many paints along with most sunscreens and toothpastes.

For a typical sample of TiO2 - Amorphous the refractive index and extinction coefficient at 632.8 nm are 2.493 and 0.000. Below are files of complete refractive index and extinction coefficients. If the file is not available for download, you can request our proprietary file by clicking "Request".

  • Proprietary encrypted file for use with Filmetrics systems
Wavelength (nm)

Refractive Index Reference - Various sources

No guarantee of accuracy - use at your own risk.