Please visit our Product Page for Hollow Cathode Lamp to know more. Various benefits of Hollow Cathode Lamps makes it ideal for usage in AAS. Heraeus’ lamps are also compatible with all major Atomic Absorption Spectrophotometry including: Can be used for almost any AA instrument.Clear signals and low distortion due to special cathode technology.Variety of single- and multi-element coded / non-coded in low and high-current, 37 mm and 50 mm lamps.Low Noise & hence better spectral responseĪs we are into supply of Hollow Cathode Lamps manufactured by Heraeus, some of the benefits of choosing Heraeus made HCLs are,.Better Lifetime compared to other lamps.The excited atoms of the inert gas and cathode are used for detection and to measure the spectrum while testing. Due to creation of plasma from the inert gas, sputtering of atoms from the cathode takes place as inert gas ions get bombarded on the cathode. When Voltage gets passed through the anode, the inert gas gets ionized. Typical Hollow Cathode Lamp SetupĪn HCL is formed of a Glass Tube that contains an anode, a cathode and inert gas. Apart from HCLs, Hollow Cathode Effect gets used in neon signages as well. Basically Hollow Cathode Effect is electrical conduction at lower voltage. Hollow Cathode Effect was first observed in 1916 by Friedrich Paschen, a German physicist, known for his work on electrical discharges. Hollow Cathode Lamps working totally depends on the hollow cathode effect. Hollow Cathode Lamps are ideal source of spectral lines that are used for testing in laboratories. The power supply current range is 0 to 25mA and a 600V ignition followed with 300V sustained power.The idea of this blog post is to cover working aspect of Hollow Cathode Lamps followed by its various advantages that fulfills Hollow Cathode Lamps’ usage in AAS. This is often aided by use of a lock-in circuit. By looking for a resonance on a data plot of the voltage signal versus source tuning parameter, the light source can be tuned to the desired frequency. To tune the light source to a specific transition frequency, a tuning parameter (often the driving current) of the light source is varied. The newly created ions cause an increase in the current across the cathode/anode and a resulting change in the voltage, which can then be measured. Indirect photoionization can then occur when electron collisions with the excited atom eject an atomic electron. By shining the light source into the HCL, one can excite or even eject electrons (directly photoionize) from the atoms inside the lamp, so long as the light source includes frequencies corresponding to the right atomic transitions. Īn HCL can also be used to tune light sources to a specific atomic transition by making use of the optogalvanic effect, which is a result of direct or indirect photoionization. These photons will then excite the atoms in the sample, which will release their own photons and be used to generate data. As these excited atoms decay to lower states, they will emit photons. Holcombe, in Encyclopedia of Analytical Science (Second Edition), 2005 Radiation sources The most common radiation source used with AA is a HCL, which consists of a tubular-shaped cathode made of the metal of interest and a simple anode. Both the buffer gas and the sputtered cathode atoms will in turn be excited by collisions with other atoms/particles in the plasma. The buffer gas ions will then be accelerated into the cathode, sputtering off atoms from the cathode. A large voltage across the anode and cathode will cause the buffer gas to ionize, creating a plasma. Basic diagram of a hollow-cathode lamp Hollow-cathode lamps from an atomic absorption spectrometerĪn HCL usually consists of a glass tube containing a cathode, an anode, and a buffer gas (usually a noble gas). An HCL takes advantage of the hollow cathode effect, which causes conduction at a lower voltage and with more current than a cold cathode lamp that does not have a hollow cathode. for atomic absorption spectrometers) and as a frequency tuner for light sources such as lasers. A hollow-cathode lamp (HCL) is type of cold cathode lamp used in physics and chemistry as a spectral line source (e.g.

Hollow cathode lamp block diagram