The photosensor is a simple cadmium sulfide cell, which measures the intensity of light bouncing back from an object as an Arduino drives the LED through all possible colors with PWM signals.

Cadmium selenide (CdSe) is an II-VI semiconductor material with a bandgap of around 1.7eV, which makes it ideal for building thin-film solar cells with ... oxide and cadmium sulfide (ZnO/CdS ...

It offers almost the same efficiency as kesterite cells based on toxic cadmium sulfide buffer layers, as the energy of the electrons between the kesterite absorber layer and ZTO buffer layer are ...