The Vasoquant 1000 is a 1-channel-photoplethysmograph that is used for venous function diagnosis. Its medical applications include a muscle pump test or the quantification of the power of venous pump with or without using compression stockings and the control of the progression of a certain venous disease. It can be adapted to different skin topographies and pigmentations because of its automatic calibration. It also has quantitative registration of the power reduction of venous pump. It stores examinations, has a volume-optimized sensor with rechargeable battery, long operating time, low costs, thermal printer, and vasoview using the Windows software.