Optical spectroscopy, AJOE

Absorption spectroscopy

Absorption spectroscopy
Infrared spectroscopy, good for measuring [CO₂] in air
- Fourier transform infrared spectroscopy uses a Michelson interferometer and Fourier transformation (FT) of the data to obtain a spectrum
- Resolution up to 0.5 cm⁻¹
- IR source: metal, metal oxide or silicon carbide rod or wire, heated to >1200 K
Ultraviolet-visible spectroscopy
- Modern UV-vis spectrometers measure the full spectrum simultaneously with a diode array detector (no moving parts, multiplexing advantage)
- Wavelength range is typically 200–1100 nm
- Resolution can be as good as 0.02 nm
- Xe lamp is the UV-visible light source