The rapid development of lasers since their launch has given a new lease to traditional optical technology and immensely boosted the development of natural science. Benefiting from the salient light absorption and light emission traits, perovskite lasers show incalculable prospects in applications of optical storage, optical interconnects, high-quality displays, on-chip photonic communications, etc. For perovskite lasers, device structure and working principle rather than just material property are also profound, especially for the realization and assessment of electrically pumped lasers, which is the prerequisite for the ultimate practical application of perovskite lasers. With this in mind, the key characteristic parameters of possible future electrically pumped lasers are discussed herein, and a systematic review of perovskite lasers is presented in a sequential order of development. To begin, the components of lasers are introduced in detail, with an emphasis on optical microcavities and diverse proposed working mechanisms, followed by introductions of representative advances in pulsed optically pumped perovskite lasers with various lasing modes, as well as state-of-the-art developments in lasing phenomenon under continuous-wave optical pumping. Finally, the challenges and fruitful progress toward electrically pumped perovskite lasers are discussed emphatically. It is hoped that this review will promote the realization of perovskite electrically pumped lasers and commercialization of perovskite lasers.

In recent years, with the rapid development of military, optical communication, biological imaging, and other fields, practical engineering applications such as fiber‐optic gyroscope, wavelength division multiplexing, and optical coherence tomography have put forward higher requirements on light sources. Amplified spontaneous emission (ASE) light source has become an excellent candidate due to its advantages such as suitable bandwidth, low coherence, and high power. Although the ASE light source is developed to a certain extent, there is still great room for improvement in the choice of gain medium and device structure. In order to accelerate the development and practical engineering application of ASE optoelectronic devices, it is of great significance to grasp the basic characteristics of the gain materials and the design of the device structure. In this review, the principle of the ASE effect and its difference with the generation of lasing are analyzed. Then, the optical gain properties of various gain materials, together with different structural types of electrically pumped ASE devices and their practical engineering applications, are summarized. Finally, the new ASE light‐emitting devices integrated with high‐gain materials and low‐cost structures are prospected to provide more ideas for their development.