Electrodeless lamps advantages

A variety of gas fills covering a fairly large range of UV and visible spectrums are available. The lamps can be changed with little difficulty, so it is easy to use the proper lamp for a specific job. The advantages of the electrodeless lamp systems are ... 

Q. What are the advantages of radiofrequency-excited electrodeless discharge lamps ... 

It has been shown that a high frequency of modulation of the electrodeless discharge lamp (e g. 10 kHz) is advantageous. This frequency is well away from the low frequency of flame noise. If the amplifier is locked-in to this high frequency via a reference signal, an optimum signal-to-noise ratio is achieved. 

Q. What advantages are offered to AFS by (i) electrodeless discharge lamps and (ii) lasers ... 

As primary sources, continuous sources such as a tungsten halogenide or a deuterium lamp can be used. They have the advantage that multielement determinations are possible. However, because of the low radiant densities saturation is not obtained and the power of detection is not fully exploited. With line sources such as hollow cathode sources and electrodeless discharge lamps much higher radiances can be obtained. Even ICPs into which a concentrated solution is introduced can be used as a primary source, through which multielement determinations become possible. 

Very many of the advantages of AAS can be directly or indirectly traced to the narrow half-intensity width of the resonance lines, i.e., the absorption of an element takes place within a very limited spectral range of about O.OOl-O.OOS nm. This advantage becomes very noticeable if the radiation sources used for excitation emit the spectrum of the analyte element in spectral lines that are narrower than the absorption lines. Hollow cathode lamps (HCLs) and electrodeless discharge lamps (EDLs) are particularly suitable as radiation sources. The latter typically provide a higher radiation intensity which results in a better signal-to-noise (S/N) ratio, particularly in the far-ultraviolet (UV) range of the spectrum. Radiation sources that emit a continuous spectrum are... 

---