An apparatus for determining the concentration of a first component in a mixture of at least two components, which have different absorption properties in the IR range, comprises image recording means which are adapted to image the mixture by means of IR radiation to produce at least one image. The apparatus further comprises image processing means which, with the aid of intensity values for pixels in the image which represent the mixture, determine the concentration of the first component in the mixture.
The invention relates to methods of assessing one or more geometric properties of a particle of a substance using an infrared spectroscopic property of the substance. The method is useful, for example, for assessing particle sizes and size distributions in mixtures containing both particles of the substance and other materials.
The invention relates to apparatus and methods for assessing occurrence of a hazardous agent in a sample by performing multipoint spectral analysis of the sample. Methods of employing Raman spectroscopy and other spectrophotometric methods are disclosed. Devices and systems suitable for performing such multipoint methods are also disclosed.