The goal of this study is to specify the ability of polychromatic light source (PAC), providing effective wavelengths in the range of 600-1200 nm (near-infrared region, NIR), to activate human platelets in platelet-rich plasma (PRP) and to achieve sustained and controlled release of growth factors from photoactivated platelets. PRP was isolated from human blood and treated with PAC in different time intervals during 1,5 and 10 min from 10 cm distance to the platelets. ATP secretion and then, calcium release from platelets significantly increased after light application. Photostimulation of platelets triggered lamellipodia extension, numerous filopodia formation, and platelet agglomeration as activation indicators. P-selectin expression was significantly increased after the application of PAC. In conclusion, PRP was successfully activated with PAC for 10 min and realized activation-dependent sustained growth factor release during 28 days. We proved that PAC which has a great potential of activation of PRP enables sustained growth factor release from PRP with a periodic use for therapeutic applications of PRP.