摘要 |
This invention relates to a supersonic nozzle (2) for injecting a gas into an infrared spectrometer, said nozzle having an aperture (24) that produces a one-dimensional expansion of said gas. The nozzle has an entrance (4) and exit (6) and between the aperture (24) and the exit (6) is a region for one-dimensional expansion of the gas. The region has two windows (14) that extend on either side of said aperture (24) towards said exit, said windows having an interior surface (30) that is set back slightly from said aperture (24). The windows (14) are made of an appropriate material such as zinc selenide to pass infrared rays and allow the gas to expand in one dimension only.
|