Photoelectric elements

Photoelectric cells

Photocell

Photoelectric cells are a type of electronic semiconductor components for converting light into electrical energy. Their actions are based on the photovoltaic effect, most often on a p-n junction. They are of three main types: photodiode, photoresistor, phototransistor and have solder terminals for SMD or THT mounting.

Types of photovoltaic components

• photodiode
• photoresistor
• phototransistor

photodiode

The photodiode is a semiconductor highly sensitive, low-inertia converter of light signals into electric current through the photoelectric effect of the PN junction. Unlike the phototransistor, the photodiode has a smaller small output power.

phototransistor

The phototransistor is a highly sensitive semiconductor low-inertia converter of light signals into electrical signals. Phototransistors can amplify the electric current generated by light. Phototransistors are preferred over photodiodes when high output power is required. The incident light beam is used as an emitter.

photoresistor

A photoresistor is a semiconductor element whose resistance depends on the degree of illumination. The principle of operation of the photoresistor is the phenomenon of photoconductivity of semiconductors. Photoconductivity is an increase in the electrical conductivity of semiconductors under the action of light. The reason for photoconductivity is an increase in the concentration of charge carriers - electrons in the conduction band and holes in the valence band. The light-sensitive layer of semiconductor material is located between the two current-conducting electrodes. Under the influence of the light flux, the electrical resistance of the layer changes several times (for some types of photoresistors, it decreases by two or three orders of magnitude).

Mounting

• SMD
• THT