DOUBLE-BEAM PHOTOMETER Russian patent published in 2001 - IPC

FIELD: measurement technology. SUBSTANCE: invention specifically falls into class of meters measuring attenuation of light by turbid medium, it can be used to examine and control surrounding aqueous medium. Double-beam photometer has leak-tight container housing radiator and collimator, beam splitter, radiation beam interrupter, illuminator, unit of optical paths of standard and measurement radiation beams ( placed in examined medium and manufactured in the form of two light-returning prisms ), light-converging device, objective and radiation detector placed in series in radiation path. Beam splitter and light converging device are made each in the form of two Lummer boxes, one of them having semitransparent surface and the other one having mirror surface. Each surface is arranged at angle of 45 degrees with optical axis that is perpendicular to principal optical axis. Surfaces are located in opposition to illuminator. Double-beam photometer is supplemented with two additional Lummer boxes with mirror surface arranged at angle of 45 degrees with principle optical axis passing through above-mentioned radiator, collimator, objective and radiation detector and at angle of 90 degrees relative one another. First additional Lummer box is placed between collimator and beam splitter and second additional Lummer box is positioned between objective and light converging device. Both additional Lummer boxes are located on principal optical axis. Disc of radiation beam interrupter is found between beam splitter and illuminator and is parallel to the latter. First light-returning prism is positioned in opposition to Lummer boxes with semitransparent surface and second light-returning prism is opposite to mirror surfaces of beam splitter and light-converging device correspondingly. EFFECT: increased accuracy of photometric measurements. 1 cl, 1 dwg