Reflectance Calculator

Calculate reflectance due to thin-film interference by entering your films below. Reflectance at wavelengths from 200nm to 2000nm may be calculated. Up to 20 films may be entered. Our Reflectance Calculator uses the same calculation engine that our thin-film measurement systems do, which is based on the complex-matrix form of the Fresnel equations.

New! Bookmark this page to save your latest plotted film stack!

We're in the process of adding new features to our Reflectance Calculator, such as the ability to calculate at non-normal angle-of-incidence. If you'd like to be e-mailed when these go live, you can let us know by using the Contact Us Now form on the right side of this page.

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Plot Start: nm
Plot End: nm
Data Point Spacing: nm
Layer # Material Thickness

Frequently Asked Questions

  • The refractive index values used in the calculations are from our online database. Please note that not all materials have index values over the entire 200-2000nm range.
  • Features that may be added to the Reflectance Calculator (depending upon demand) include graded layers, graded interfaces, roughness, superlattices, the ability to add custom materials, the ability to designate angle of incidence and polarization, and the ability to save film stacks.
  • Your feedback on the relative priority of the above listed features would be welcomed (use our standard enquiry form).

Enter the refractive index of your material at 632.8nm. The Calculator will add dispersion that approximates the average dispersion of materials with that refractive index.

Refractive Index @ 632.8nm: