Abstract
The background oriented schlieren (BOS) technique is one of the visualization techniques that enable the quantitative measurement of density information in the flow field with very simple experimental setup. The random dot pattern images are commonly used as background in BOS technique and local displacement of dot pattern is calculated by image analysis with validation between two images - without flow and with flow images. This displacement is caused by variation of the index of refraction related to density gradient. In this report the quantitative measurement by colored grid background oriented schlieren (CGBOS) technique. A measurement of supersonic flow field around an asymmetric body is tested at a JAXA-ISAS supersonic wind tunnel. Furthermore an improvement in resolution of BOS measurement by using telecentric optical system.