We demonstrate the fabrication of fiber-optic Fabry-Perot interferometer (FPI) temperature sensors by bonding a small silicon diaphragm to the tip of an optical fiber using low melting point glass powders heated by a 980 nm laser on an aerogel substrate. Among all the reported applications, optical waveguides have been widely exploited to. This article explores the structure, working principles, advantages, and disadvantages of Fiber Optic Temperature Sensors. Temperature measurement can be achieved through various methods, including: However, these traditional systems often suffer from limited immunity to electromagnetic. Therefore, this type of sensors is inept for gauging temperature in microfluidic or nano-sized devices, in extreme marine environments, and underground geological sites where long distance measurement with precision is required.