Patent attributes
A torch for producing an inductively coupled or microwave induced plasma for use in spectrochemical analysis. The torch includes a central tube (25) for conveying a flow of a gas carrying sample aerosol to a plasma (17) produced in the torch. The tube (25) has an inlet (31) and an outlet (39) of smaller size than the inlet and is shaped to deliver a substantially laminar flow of the gas at the outlet (39). The tube (25) is tapered along at least a substantial portion of its length such that its cross-section area gradually and smoothly reduces towards its outlet (39) along at least a substantial portion of its length. It has been found that such a tapered tube is resistant to obstruction by salts deposited from samples containing high levels of dissolved solids.
