A technique for making holograms easily and for measuring simultaneously the behaviour of particles of different sizes and/or shapes

Abstract

A new technique for rapidly discriminating shapes and/or sizes of micrometre size particles which are spatially distributed on a large scale has been developed. The technique is based on multiplexed matched spatial filtering, which is a kind of Fourier holographic filtering technique. Using the technique, large view visualization of the spatial distribution and the spatial behaviour of specific particles (e.g. aerosols, allergen particles, red blood cells, etc) can be realized. To make the multiplexed matched spatial filter (MMSF), a new material for hologram recording has been applied. The material is a photoconductor plastic which is processed by a solvent vapour and a corona discharge. The method of hologram recording is a dry process, which processes the material in several minutes at the initial settings of the device. Therefore, the MMSF can be made very easily in a short time. In the research, the discrimination of spatial behaviour of moving particles of different shape and/or size has been carried out by the MMSF made by the photoconductor plastic material.