Method and apparatus for determining the quantity ratio of two components of a multi-substance mixture

Abstract

Abstract A method for determining the quantity ratio of two components of a multi-substance mixture whose absorption bands are adjacent to each other and overlap comprises using an interference filter which is rotated in a uniform rotation about a first axis through the filter plane which forms with a perpendicular erected on the filter plane a fixed angle β which is not equal to zero. The filter is rotatably arranged about a second axis through the filter plane and the method is characterized by adjusting the angle α which the axis of rotation forms with the ray in the range of β is less than α so that a signal corresponding to the first derivative of the spectral intensity distribution of the radiation transmitted by the substance mixture just passes through zero and a quantity correlated with this angle is used as a measure of the quantity ratio. The radiation modulator for determining the quantity ratio includes a housing having an opening for the passage of the light ray therethrough and a filter in the housing in the path of the beam. The filter is mounted for rotation about a first axis comprising the axis of the filter and is mounted for pivoting about a second axis also going through the filter. The first axis is such that the area normal thereof forms with the first axis a fixed angle β and the first axis is rotatable about the second axis and an angle α is formed between the first axis in the ray direction which may be read and indicated and the filter is adjustable to vary the angle.

Inventors

• 👤 Thaddaus Kraus

Bibliographic Details