An electronic device using a novel optical module is provided.The optical module includes a first light-emitting element, an optical conversion element, and a first light-receiving element. The first light-emitting element includes a plurality of fluorescent substances and a light-emitting diode. The optical conversion element includes a first optical filter. The light-emitting diode emits first light, and the fluorescent substances can emit second light by being excited by the first light. The first optical filter can form third light having a wavelength range longer than 680 nm from the second light. The first light-receiving element has the function of detecting the third light, and the first light-receiving element functions as a sensor detecting the existence of a shielding object on a light path connecting the first light-emitting element and the first light-receiving element. Furthermore, the second light formed by the optical module can function as a light source of the display device.