![Spectral lamps, explained by RP Photonics Encyclopedia; calibration lamps, low pressure gas discharge, wavelengths, helium, neon, sodium, cesium, mercury, cadmium Spectral lamps, explained by RP Photonics Encyclopedia; calibration lamps, low pressure gas discharge, wavelengths, helium, neon, sodium, cesium, mercury, cadmium](https://www.rp-photonics.com/previews/spectral_lamps.png)
Spectral lamps, explained by RP Photonics Encyclopedia; calibration lamps, low pressure gas discharge, wavelengths, helium, neon, sodium, cesium, mercury, cadmium
Lighting-Gallery.net - Lamps - Low Pressure Sodium/GE NA-1 Lab-Arc low pressure sodium spectral lamp
![Na Low-Pressure Spectral Lamp (230 V, 50/60 Hz) - 1003163 - OSRAM - U21833-230 - Spectrum Tubes and Spectrum Lamps - 3B Scientific Na Low-Pressure Spectral Lamp (230 V, 50/60 Hz) - 1003163 - OSRAM - U21833-230 - Spectrum Tubes and Spectrum Lamps - 3B Scientific](https://www.3bscientific.com/imagelibrary/U21833-230/U21833-230_01_Na-Low-Pressure-Spectral-Lamp-230-V-5060-Hz.jpg)