(Invited) Detection of Wavelength Information by Filter-Free Wavelength Sensor and Its Applications

This paper introduces the wavelength and light intensity detection method using the filter-free wavelength sensor without optical components. Using a modified CMOS process, we developed a filter-free wavelength sensor with a photogate structure. The sensor can detect light intensity and wavelength without optical filters based on the dependence of the light absorption depth in silicon. Using a developed sensor, we demonstrated a wavelength, spectral shift, and light absorption detection method to apply various fields. In the future, we will continue research to realize an optical sensor system that is more compact, sensitive, and selective.