Photoreceptor cell, a photosensitive cell in the retina of vertebrate eyesSimple eye in invertebrates (Ocellus), photoreceptor organ ("simple eye") of invertebrates often composed of a few sensory cells and a single lensEyespot apparatus (microbial photoreceptor), the photoreceptor organelle of a unicellular organism that allows for phototaxis
In biochemistry:
Photoreceptor protein, a chromoprotein that responds to being exposed to a certain wavelength of light by initiating a signal transduction cascadePhotopigment, an unstable pigment that undergoes a physical or chemical change upon absorbing a particular wavelength of light; also seePhotosynthetic pigment, molecules involved in transducing light into chemical energy
In technology:
Photodetector or photosensor, a device that detects light by capturing photons reference
