连续域束缚态（bound state in the continuum, BIC）是具有特殊性质的本征模式，其处于辐射连续域的频率范围内却具有完全局域性，具有无穷大的品质因子和特殊的动量空间的偏振特性，对集成光学、拓扑光学、信息光学等领域的发展起着重要作用。目前，支持BIC的平面介质结构由于其相比于金属结构具有更低的损耗和更高的损伤阈值等优点，被人们广泛研究，然而，涉及该方面的综述，英文版的较多，但是内容较旧，而中文综述较少。本文对平面介质结构中的BIC的研究进展进行综述，旨在系统地总结其研究现状，并展望其发展前景。本文首先介绍了BIC的概念、分类、基本性质和重要的理论分析方法，然后着重对平面介质结构中的BIC的研究进展和其在激光、高灵敏度传感器、光波导等领域的应用进行了总结，最后对其研究现状和未来图景进行了讨论。

Bound states in the continuum (BICs) are eigenmodes with special properties, which are in the frequency range of the radiative continuous domain but fully localized, with an infinite quality factor and special polarization properties in momentum space, and which play an important role in the development of integrated optics, topological optics, and informational optics. Currently, planar dielectric structures supporting BICs are widely studied due to their advantages such as lower loss and higher damage threshold compared to metallic structures. There are more reviews in this field in English, but the contents are older, while there are fewer reviews in Chinese. In this paper, we review the research progress about BICs in planar dielectric structure, aiming to systematically summarize the current status of its research and give an analysis of its future development. This paper firstly introduces the concepts, classifications, basic properties and important theoretical methods of BICs, and then focuses on the research progress of BICs in planar dielectric structures and their applications in fields of lasers, optical waveguides and so on, and finally discusses the current situations and the future prospects of the researches related to BICs in planar dielectric structures.