Contactless medium analysis for chocolate, dough mfr. and ophthalmic diagnoses - comprises exposing medium to low pressure compressed airjet rising to high pressure for short time to create crater, reflecting IR off base, etc

Simultaneous non-contact measurement and mathematical modelling of material contents and parameters, e.g. moisture, fat and protein contents and viscosity (internal pressure), esp. of highly viscous to fluid media for ophthalmic diagnostics using compressed air and IR radiation of various wavelengths comprises (a) exposing the medium (eye) to a compressed air jet initially at low pressure and then at high pressure for a few multisecs. to produce a 'crater' of depth dependent on viscosity (internal pressure) and to produce a variable restoration pressure and (b) converting the IR radiation, reflected from the crater base, by sensors into electronic signals supplied to a measurement computer which processes the material contents and parameters to produce a mathematical model and which displays the material content values resulting from variable intensity IR absorption at special reference and measurement wavelengths. The process pref. employs oil-free compressed air at 1-500 Pa and 501-5000 Pa pressure levels and IR radiation with reference and measurement wavelengths of 1.82 microns and 1.94 microns for moisture, 1.65 microns and 1.725 microns for fat and 1.65 microns and 1.82 or 2.18 microns for protein. The compressed air is fed to the medium (eye) through an opaque longitudinally divided polycarbonate light-guiding tube (4). USE/ADVANTAGE - The process may be used to control mfr. of dough, chocolate, synthetic fibres or the like, but is esp. useful in ophthalmic diagnostics. It provides inexpensive, rapid (milliseconds) and high precision measurement and mathematical modelling.