fotoelektronik

Fotoelektronik, or photoelectronics, is the branch of electronics that studies and uses the interaction between light and electronic systems to generate, detect, or modulate electrical signals. It encompasses devices and materials that convert light to electrical signals and vice versa, or that control light with electronic means.

The foundation is the interaction of photons with semiconductors. Absorption of photons with energy above a material’s band gap creates electron–hole pairs, enabling photoconductive and photovoltaic effects. The concept traces to the photoelectric effect explained by Einstein in 1905, establishing quantum mechanics principles and the energy relation of photons to emitted electrons. In detectors, light-induced charge carriers produce current or voltage; in emitters, electrical energy drives light emission.

Common devices include photodiodes, phototransistors, and photomultipliers for detecting light; solar cells and photodetectors for energy conversion; and image sensors such as CCD and CMOS arrays. Integrated optoelectronic components combine light sources (LEDs, lasers) with detectors and signal-processing circuitry on a single platform. Materials of interest include silicon for mainstream detectors, III–V semiconductors like GaAs and InP for high-speed and infrared applications, and emerging materials such as perovskites and two-dimensional materials.

Applications span optical communications, where photoelectronics enable high-speed receivers; imaging and vision systems; solar power conversion; industrial sensing, environmental monitoring, and medical imaging. Performance metrics include responsivity, quantum efficiency, response time, noise, and spectral range.

The field has evolved from the early understanding of light–matter interaction to sophisticated optoelectronic integrated circuits. Ongoing research focuses on higher efficiency, faster detectors, broader spectral coverage, and the integration of light sources and sensors into compact, low-power systems.