Filter‐Less Polychromatic Recognition in One Photosensitive Oscillator via Dual‐Perception Feature Decoupling

Filter-less polychromatic photodetectors play a critical role in miniaturized optoelectronic integration for spectral recognition, color imaging, and biometrics. However, parallel integration of several absorption-selective semiconductors in one polychromatic pixel is indispensable, while polychromatic perception via a single semiconductor without optical components assistance seems difficult to achieve. Here, a filter-less photosensitive ring oscillator (PSRO) based on a single amorphous semiconductor is demonstrated for polychromatic recognition. The distinguishable resolving ability for both wavelength and intensity in PSRO originates from decoupling oscillation frequency and relaxation character. The intrinsic localized defective states of amorphous IGZO contribute to relaxation character and fifth-order oscillation architecture constructs frequency feature. The response oscillation frequency of PSRO up to ≈160 Hz and has recognizable detection in primary color waveband (450, 532, and 635 nm) range from 50 to 1500 µW cm^-2. An integration system based on PSRO with a response processing circuit has been demonstrated for application feasibility in polychromatic recognition. This work offers a kind of new methodology for polychromatic preceptors and advanced spectrometers.