Abstract: A reagent blood coagulation that causes an increase in turbidity changes when added to a plasma sample containing a substance activating coagulation factor activating such as tissue thromboplastin, phospholipid and thrombin, calcium ion, and molecular substance such as high molecular vinyl and a high molecular polysaccharide. By adding a molecular substance to the reagent, the turbidity change due to blood coagulation is increased, and hence the changing quantity of transmitted light or scattered light increases, thereby making it possible to achieve a more accurate detection. Besides, by adjusting the electric conductivity, pH and osmotic pressure to proper values, the turbidity change due to blood coagulation may be further amplified.

Abstract: A standard substance for optical calibration is produced by mixing a proportion of a scattering substance with a first silicone liquid. The optical properties of the first liquid are measured and a further amount of the first liquid is added to the original mixture to provide a desired optical property. Then, the mixture is further mixed with a second silicone liquid which initiates a curing process. The final mixture is poured into a transparent vessel for curing. The transparent vessel, with the cured final mixture inside, is useful as a standard substance for calibration of an optical equipment. A technique for calculating the proportions of the mixtures is disclosed.