定义：电子器件与光相互作用的技术。

光电子学是与光相互作用的电子学器件技术，光可能处于可见光，红外光或者紫外光光谱区域。一些光电子学器件的例子如下： 

• 半导体激光器和发光二极管（LED），将电能转化为光 
• 光电探测器（例如，光电二极管），将光信号转化成电流 
• 电光调制器，采用电控制的信号来调控光的功率，相位或者偏振态 
• 电吸收调制器和声光调制器 
• 光子集成回路，在芯片上集成电子学和光学器件 

光电子学器件可用在很多应用领域，例如光纤通信，激光技术，和各种光学测量。 

Definition: the technology of electronic devices that interact with light

Alternative term: optronics

Optoelectronics (also called optronics) is the technology of electronic devices that interact with light, which may be in the visible, the infrared or ultraviolet spectral region. Examples of optoelectronic devices are:

• laser diodes, superluminescent diodes and light-emitting diodes (LEDs), converting electrical energy to light
• photodetectors (e.g. photodiodes and phototransistors), converting optical signals into electrical currents
• imaging detectors, based on electronic image sensors
• electro-optic modulators, used for manipulating the power, phase or polarization of light with an electrical control signal
• electroabsorption modulators
• opto-isolators for transmitting analog or digital signals while maintaining electric isolation
• photonic integrated circuits, hosting electrical and optical components on some kind of chip (see also: silicon photonics)
• photoemissive detectors such as phototubes and photomultipliers, also image intensifiers

Optoelectronic devices are used in a wide variety of application areas, such as optical fiber communications, laser technology, and all kinds of optical metrology.

Optoelectronics is largely based on semiconductor materials. These exhibit suitable bandgap energies for absorbing e.g. near-infrared and visible light, and their electric conductivity (albeit not perfect) is also essential for such applications. In both aspects, dielectrics would be hard to use, while metals serve mostly as conductors, apart from the exploitation of the external photoelectric effect in some photodetectors.

Indirect band gap materials such as silicon and germanium are often sufficient for exploiting absorption processes, for example in photodetectors, but are generally less suited for emitting light. This is a substantial challenge for silicon photonics, where however various kinds of solutions has been found. Still, emitting devices such as laser diodes are largely based on direct band gap materials, particularly of III–V type – for example, gallium arsenide and indium phosphide.