FIELD: physics.
SUBSTANCE: system includes a sample accommodating area, a light source, a collimating lens, a first lens, a second lens and a sensor. The sample accommodating area is made from optically transparent material with possibility of placing an analysed sample in the said area. The collimating lens receives light from the light source and directs the light to the sample accommodating area. The first lens receives conventional and scattered light passing through the sample with a first divergence angle. Light with a first acceptance angle falls on the first lens. Light with a second divergence angle which is less than the first comes from the first lens. The second lens receives light from the first lens and an essentially collimated beam comes from the second lens.
EFFECT: invention increases accuracy of measuring concentration of analysed substance.
45 cl, 14 dwg
