Particle monitoring apparatus and vacuum processing apparatus

Abstract

A particle monitoring apparatus comprises: a light source configured to emit a light having a given intensity; a projecting optical system configured to converting the light emitted from the light source into a band-shaped light flux and to lead the light flux onto a flow passage of a given gas stream so that the given gas stream may pass the band-shaped light flux; a light detector configured to detect the intensity of the light: a detecting optical system configured to lead the light scattered by particles contained in the gas stream and passing the light flux to the light detector, and a particle detector configured to determine sizes of the particles passing the light flux based on intensities of the scattered lights detected by the light detector and to count the number of the particles passing the light flux for a given period, wherein the light intensity of the band-shaped light flux is set to have an almost uniform distribution in a horizontal direction.

Dependencies are inferred from the claim text.