Optical and electrical hybrid flexible printed circuit boards with unique photo-defined polymer waveguide layers have
been investigated. The photo-defined waveguides are made by simple pattering process, known as "Photo-addressing". In
the process, only ultraviolet irradiation through a photo mask over photosensitive dry film is carried out to form entire
waveguide patterns, and any additional steps like etching or developing are not required.
We are now giving high priority to further process development how to integrate them with conventional flexible printed
circuit boards, and gathering data of basic characteristics, properties and reliabilities of those kinds of hybrid product.