ruby laser

https://doi.org/10.1351/goldbook.R05427
A pulsed source of coherent radiation emitting mainly at 694.3 \(\text{nm}\) from chromium ions (Cr3+) in aluminium oxide.
See: laser, solid state lasers
Source:
PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2272 (https://doi.org/10.1351/pac199668122223)