A Bioinspired Retinomorphic Device for Spontaneous Chromatic Adaptation

Chromatic adaptation refers to the sensing and preprocessing of the spectral composition of incident light on the retina, and it is important for color-image recognition. It is challenging to apply sensing, memory, and processing functions to color images via the same physical process using the complementary metal-oxide-semiconductor technology because of redundant data detection, complicated signal conversion processes, and the requirement for additional memory modules. Inspired by the highly efficient chromatic adaptation of the human retina, a 2D oxygen-mediated platinum diselenide (PtSe₂ ) device is presented to simultaneously apply sensing, memory, and processing functions to color images. The device exhibits a wavelength-dependent bipolar photoresponse and the linear pulse-number dependence of photoconductivity, which is dominated by the photon-mediated physical adsorption and desorption of oxygen molecules on bilayer PtSe₂ . The proposed retinomorphic device shows superior image classification accuracy (over 90%) compared to an independent pseudocolor channel (less than 75%). Hence, it is promising for developing artificial vision perception systems with reduced architectural complexity.