SPIE Proceedings [SPIE 7th International Symposium on Advanced Optical Manufacturing and Testing Technologies (AOMATT 2014) - Harbin, China (Saturday 26 April 2014)] 7th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronics Materials and Devices for Sensing and Imaging - Continuous-wave photoinduced absorption studies in long lived photoexcitation of π-conjugated polymer and fullerene blended films