14.10 : 原子発光分光法: 機器

The atomic emission spectrometer comprises a sample nebulizer, a plasma source, a wavelength-isolating device, transducers, and a microprocessor controller.

The sample is drawn using a peristaltic pump and transported to a nebulizer, which converts the sample solution into fine droplets.

Larger droplets are directed to a drain, while the fine droplets are carried by argon gas to the plasma—commonly, direct current plasma or inductively coupled plasma.

In the plasma, the samples are atomized to gas-phase atoms and ions and, on further collision, get excited.

The atomic or ionic emission from the plasma is then separated by a monochromator, polychromator, or spectrograph.

Monochromators separate individual wavelengths sequentially through a single exit slit, whereas polychromators with several exit slits isolate multiple wavelengths concurrently.

Alternatively, a spectrograph enables a range of wavelengths to be monitored simultaneously.

The isolated radiation is converted into electrical signals by single or multiple photomultiplier transducers or array detectors and is further analyzed.