Refractive Index Correction Calculator

How to Use This Calculator

1. Enter the original refractive index (n₀) of your material.
2. Input the current temperature of the material in °C.
3. Specify the wavelength of light used for measurement in nanometers (nm).
4. Click the "Calculate" button to obtain the corrected refractive index.

Understanding the Formula

The calculator uses the following formula to correct the refractive index:

n_t = n_₀ - (α × ΔT) + (β × λ^-1)

Where:

• n_t is the corrected refractive index at the specified temperature and wavelength.
• n_₀ is the original refractive index at a reference temperature (typically 20°C).
• α is the thermal coefficient of the material (how much the refractive index changes per °C).
• ΔT is the temperature difference from the reference temperature (T_ref - T_meas).
• β is the wavelength dependence coefficient (how much the refractive index changes per nanometer).
• λ is the wavelength of light in nanometers.

Example

If a material has an original refractive index of 1.5 at 20°C, and you measure it at 25°C with a wavelength of 589 nm, the corrected index would be calculated as follows:

n_t = 1.5 - (0.00025 × (20 - 25)) + (0.0001 × (1 / 589))

n_t = 1.5 - (-0.00125) + (0.000000169)

n_t = 1.5014