Method and device for detection and/or measurement of impurities in droplets

Measurement device for the detection and/or measurement of particles in a fluid, the measurement device comprising:

• a fluid source configured to produce a flow of fluid along a fluid flow path,
• a laser source positioned for emitting a laser beam of laser light in a measurement volume of the fluid flow path;
• a first lens set configured to collect a first laser light scattered in the measurement volume by particles contained in the flow of fluid;
• a scattered light detecting means configured to detect a presence of a particle in the fluid flow path through detection and measurement of laser beam light scattered on different angles by said particle,
• characterized in that it further comprises
• a Raman and fluorescence detecting means configured to detect a Raman scattering signal emitted by the fluid and a Fluorescence signal emitted by said particle upon excitation by said laser beam,
• wherein said first lens set is configured for focusing the scattered light in a line at a focal distance of the lens set, said line being transverse to a flow direction of the flow of fluid in said measurement volume and wherein said first lens set is configured for focusing said scattered light in a line by focusing said scattered light in a direction parallel to said flow direction and for making the rays of scattered light parallel to each other in a plane perpendicular to said flow direction
• further comprising a second lens set for collecting the Raman signal emitted by the fluid molecule and fluorescence signal emitted by the particle upon excitation by said laser beam,
• wherein the Raman and fluorescence detecting means is a photo-detector positioned for the detection of laser light collected by the second lens set,
• wherein the photo-detector is a linear multipixel detector configured for capturing the laser light focused by the lens set, wherein said linear multipixel detector is positioned at a distance from the focal distance of the lens set and oriented with its longitudinal axis parallel to said line.