Introduction: Wholesale narrow linewidth diode laser modules sustain spectral linewidth under 0.1 nm and thermal drift in the vicinity of 0.01 nm/°C for secure, specific operation in variable environments.
because the https://www.reallightlaser.com/cw-qcw-lasers/08ltr-mini-single-mode-free-space-narrow-linewidth-diode-laser-components/