Fiber-optic dielectric multilayer temperature sensor: in situ measurement in vitreous during Er : YAG laser irradiation

A fiber-optic instrument for temperature measurement is presented. The sens ing element consists of an optical dielectric multilayer system acting as a micro-interferometer which is deposited on a single-mode fiber tip. The se nsitivity of the implemented system is theoretically derived and experiment ally determined by a calibration measurement. The small size of the probe m akes the system well-suited, for instance, for endoscopic in vitro and in v ivo measurements in medical applications, especially in small samples. The sensor is used for the investigation of the transient thermal behavior of v itreous during Er:YAG laser irradiation in order to study the local thermal effects that are important to minimize the potential for unintentional inj ury in laser vitrectomy and laser vitreoretinal surgery. (C) 2000 Elsevier Science Ltd. All rights reserved.