[The experiment of searching a biological origin traces with an expert light source].

The aim of the work is assessment of the efficiency of detection the biological traces by various sources of expert light. Hidden traces of blood, saliva, semen and urine were detecting on various types of carrier objects. Was described the biological appearance depended on both the nature of the material and the properties of the carrier object: color, the presence of luminescent substances in the composition, the nature of the surface (smooth, fleecy), thickness, ability to adsorb and conduct liquid.