Nernst glower
From Wikipedia, the free encyclopedia
The Nernst glower is an obsolete device for providing a continuous source of (near) infrared radiation for use in spectroscopy. Typically it was in the form of a cylindrical rod or tube composed of a mixture of certain oxides such as zirconium oxide (ZrO2), yttrium oxide (Y2O3) and erbium oxide (Er2O3) at a ratio of 90:7:3 by weight. They operated by being electrically heated to about 2000 °C. Initially they required external heating because the material is an insulator at room temperature.
It has been replaced by a similar device known as a globar made of silicon carbide (SiC) that operates at about 1100 °C. The globar does not require an external preheater as it is an electrical conductor at any temperature. It is also better suited for use in evacuated systems.
[edit] See also
Lighting and Lamps
|
||
---|---|---|
Incandescent: | Conventional - Halogen - Parabolic aluminized reflector (PAR) | |
Fluorescent: | Compact fluorescent (CFL) - Linear fluorescent - Induction lamp | |
Gas discharge: | High-intensity discharge (HID) - Mercury-vapor - Metal-halide - Neon - Sodium vapor | |
Electric arc: | Arc lamp - HMI - Xenon arc - Yablochkov candle | |
Combustion: | Acetylene/Carbide - Candle - Gas lighting - Kerosene lamp - Limelight - Oil lamp - Safety lamp | |
Other types: | Sulfur lamp - Light-emitting diode (LED) - Fiber optics - Plasma |