Introduction
This document provides a detailed characterization of pulsed lasers using the MIDWAVE Spectrometer, focusing on its application for mid-infrared laser sources.

Spectroscopy for Pulsed Laser Sources
The MIDWAVE Spectrometer is designed for inspecting the emission spectra of pulsed mid-infrared lasers. Unlike traditional FTIR or monochromator spectrometers, it captures the entire pulse simultaneously, eliminating issues related to pulse timing. It supports a bandwidth of 2.0 - 5.0 µm and a resolution down to 2.5 cm^-1, making it a reliable tool for laser characterization.

Ultra-Fast Characterization of Lasers
The spectrometer can capture spectra at rates up to 130 kHz, suitable for ultra-fast spectral characterization. Examples include:

• A 3330 nm laser with a drive current modulated at 1 kHz, measured at 80 kHz, showing increased output and wavelength changes.
• Single-pulse measurements from a mid-infrared supercontinuum source at 40 kHz, measured at 80 kHz, demonstrating consecutive pulse spectra.

The spectrometer's high sensitivity and fast readout rate make it versatile for various fast laser characterization applications.

Data Analysis
The document includes graphical data:

• Left: Spectra of a 3330 nm laser under 1 kHz modulation, showing amplitude increase and wavelength shift.
• Top Right: Consecutive single-pulse spectra of a pulsed mid-infrared supercontinuum laser at 40 kHz.
• Bottom Right: Calculated relative intensity noise (RIN) from the data.

This data aids in calculating the spectral density of relative intensity noise, enhancing the understanding of laser performance.