IRsweep

IRis-F1 Dual-comb Spectrometer

🟡 Special Request

The IRsweep IRis-F1 spectrometer uses a dual frequency comb laser source to provide high signal-to-noise measurements with microsecond time resolution.

This spectrometer is an excellent complement to broadband FT-IR measurements where information about the dynamics of the system of interest is limited by the useful time resolution of rapid-scan measurements or by the reproducibility requirements of step-scan measurements.

Time-Resolved Measurement Modes

There are a number of different measurement modes with implications for time resolution.

Static Measurement

Closest to a traditional FT-IR rapid-scan measurement, but with faster measurement rates and times.

• Traditional background measurement

• Sample measurements can be repeated as needed

• Rapid multiple static acquisition limited by repetition rate / signal-to-noise requirements

  • Example: 1 ms acquisition has minimum 7 ms duty cycle for up to 3.4 s with good noise floor

  • Duty cycle can be specified

  • Measurement can continue indefinitely at reduced duty cycle (256 ms for above 1 ms example)

• Start of measurement can be triggered

Triggered Static

Same as Static Measurement, except each measurement is controlled externally.

• Single trigger to collect single measurement

• Duty cycle and repetition rate are determined by external trigger

Triggered Time-Resolved

Best time resolution, similar to FT-IR step-scan measurement.

• Background is collected as pre-trigger samples for each repetition

• Requires a sample system with a reproducible trigger (like step-scan)

• Finite time window

• Sample measurement repeated to build S/N (co-addition)

• Default time resolution is 4 µs, minimum is 1 µs

More Information

Thorlabs website has an introduction to the dual-comb laser technique and advantages: https://www.thorlabs.com/irsweep-dual-comb-spectrometers