19 ~ 25 August 2012 (Week 3)

(Research) 

Title of  Activity

-Project research -photoplethysmography (ppg)

Objective

-To know what is ppg ?
-Make it as a literature review.

Content /procedure

search about information from internet 

photoplethysmography (ppg)

        

                The photoplethysmograph is a sensor that uses an emitter-receiver pair to determine blood flow.  A light emitting diode is used to transmit light through the skin.  The receiver picks up the transmitted signal, which is then analyzed with signal processing techniques.  The pulse wave is produced by the changes in blood volume in the arteries and capillaries.  Changes in blood volume produce changes in the optical absorption of the transmitted signal.  

                 The light transmitted through the tissue can be highly scattered or absorbed depending on the tissue.  The detector, which is positioned on the surface of the skin, can detect the reflection or transmission of waves from various depths and from highly absorbing or weakly absorbing tissues .  Regardless of the absorbency of the tissues and skin, it is assumed that the amount of light absorbed and/or reflected by these tissues will remain constant .

Result & Analysis

- Got some knowledge about ppg .