Patent ID: 6155097
Filing Date: 2000-12-05
Classification: G01N

Abstract:
An improved inlet system for increasing the concentration ratio and the density of trace vapors diffusely dispersed in a carrier medium forming an input mixture, which input mixture is, in operation, provided to an input of said inlet system and where said trace vapors in said input mixture are at a first concentration ratio with respect to said carrier medium and at a first density value in said input mixture, the improvement comprising:a membrane apparatus having an input and an output, said membrane apparatus input for receiving said input mixture and for preferentially extracting a portion of said trace vapors from said carrier medium and for providing a second higher concentration ratio of said trace vapors with respect to said carrier medium at said membrane apparatus output than said first concentration ratio at said membrane apparatus input and;a compressor having an input and an output, said compressor being a turbomolecular pump;said membrane apparatus being fixedly disposed across said input of said turbomolecular pump whereby, in operation, said membrane apparatus provides at said output said second higher concentration ratio of trace vapors and said turbomolecular pump establishes and maintains a partial vacuum at said output of said membrane apparatus and thereby maintains a pressure driving gradient of said trace vapors across said membrane apparatus while simultaneously providing higher density of said trace vapors at said output of said turbomolecular pump compared to the density of said trace vapors at said input of said turbomolecular pump whereby the density of said trace vapors at said output of said turbomolecular pump is at a second density value which is higher than said first density value.