光学传感检测技术因具有精度高、低延时和可成像等优势而得到广泛应用。随着大数据和物联网等信息技术的迅速发展，对检测平台小型化和便携性的需求日益迫切。为了克服现有技术对大型专用设备的依赖，提高对现场快检、轻载荷平台等应用场景的适用性，近年来，基于微纳光学的片上集成光学传感检测技术受到了极大关注。通过集成光源、光学传感单元与光电探测单元、以及发展片上光色散等技术，可以有效地实现光学传感信号提取和光电信号转换的片上集成，从而实现系统的微型化和多功能集成。文中介绍了相关技术原理和技术发展现状，分析了现有技术的优缺点，讨论并总结了未来的发展方向和应用前景。

Gas identification and concentration measurements are important for both understanding and monitoring a variety of phenomena from industrial processes to environmental change. Here a novel mid-IR plasmonic gas sensor with on-chip direct readout is proposed based on unity integration of narrowband spectral response, localized field enhancement and thermal detection. A systematic investigation consisting of both optical and thermal simulations for gas sensing is presented for the first time in three sensing modes including refractive index sensing, absorption sensing and spectroscopy, respectively. It is found that a detection limit less than 100 ppm for CO₂ could be realized by a combination of surface plasmon resonance enhancement and metal-organic framework gas enrichment with an enhancement factor over 8000 in an ultracompact optical interaction length of only several microns. Moreover, on-chip spectroscopy is demonstrated with the compressive sensing algorithm via a narrowband plasmonic sensor array. An array of 80 such sensors with an average resonance linewidth of 10 nm reconstructs the CO₂ molecular absorption spectrum with the estimated resolution of approximately 0.01 nm far beyond the state-of-the-art spectrometer. The novel device design and analytical method are expected to provide a promising technique for extensive applications of distributed or portable mid-IR gas sensor.