Calibrate channels using trusted spectral references. Review dispersion, offsets, and peak positions clearly. Improve wavelength mapping for accurate optical measurements today.
| Reference | Channel Position | Known Wavelength (nm) | Use |
|---|---|---|---|
| Line A | 125.0 | 435.833 | First anchor |
| Line B | 842.0 | 546.074 | Second anchor |
| Unknown Peak | 510.0 | Calculated | Target wavelength |
This calculator uses a linear wavelength calibration between two known spectral lines.
Slope: m = (λ2 − λ1) / (x2 − x1)
Intercept: b = λ1 − m × x1
Calibrated Wavelength: λ = m × x + b
Here, λ is wavelength in nanometers and x is the adjusted channel position after subtracting any zero offset.
If FWHM is supplied, the estimated spectral width is:
Estimated Width: Δλ = |m| × FWHM
Enter two reference channel positions from your detector.
Enter the known wavelengths for those reference peaks.
Add the unknown peak channel you want to identify.
Enter a zero offset if your instrument uses corrected indexing.
Add FWHM only when you want an estimated spectral width.
Press the calculate button to view the result above the form.
Use the CSV button to save tabular results.
Use the PDF button to export a clean summary.
Spectrometer wavelength calibration converts detector channels into meaningful wavelengths. Good calibration improves line identification, trend analysis, and repeatability. A simple two-point method works well when the instrument behaves nearly linearly across the working range.
Reference lines should be stable, sharp, and known accurately. Choose anchors that bracket the unknown peak whenever possible. This reduces interpolation error and makes the calculated dispersion more useful for later measurements and quick laboratory checks.
Zero offset can matter when a detector origin changes during setup or software indexing. Correcting that shift before calibration keeps the linear model cleaner. Optional FWHM input also helps estimate the spectral width represented by your measured peak on the detector.
This page is useful for optics labs, teaching setups, and routine emission analysis. It also supports simple result exports, so the calibration values can be archived, shared, or reviewed later without rebuilding the entire measurement session.
It converts an unknown detector channel into wavelength using two known reference lines. It also reports dispersion, intercept, and an optional spectral width estimate.
Two reference points define the straight calibration line. With only one point, you cannot determine both slope and intercept reliably.
It is suitable when the working detector region behaves nearly linearly. For wide ranges or curved response, a higher-order calibration may be better.
Dispersion is the wavelength change per detector channel. It shows how much wavelength shifts when the detected peak moves by one channel.
Zero offset corrects a constant channel shift caused by indexing or alignment. The calculator subtracts it before building the calibration equation.
FWHM helps estimate spectral width in wavelength units. The calculator multiplies channel width by the calibration slope magnitude.
Yes, that is usually best. Interpolation between anchors is generally more reliable than extrapolation beyond them.
Yes. The results section includes CSV and PDF export buttons after calculation, so you can save calibration values for later use.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.