A microfiber coupler tip thermometer

Abstract

A compact thermometer based on a broadband microfiber coupler tip is demonstrated. This sensor can measure a broad temperature interval ranging from room temperature to 1283 ºC with sub-200 µm spatial resolution. An average sensitivity of 11.96 pm/ºC was achieved for a coupler tip with ~2.5 µm diameter. This is the highest temperature measured with a silica optical fiber device.

High Sensitivity Fiber Refractometer Based on an Optical Microfiber Coupler

“…This microfiber coupler has many potential applications, for example in high performance fiber lasers, fiber sensors and optical coherence tomography systems. Furthermore MFC based thermometers [9], [10] and ultra-broadband 3 dB coupler [11] have also been demonstrated recently. Earlier research on the dependence of the coupling coefficient of traditional fused bi-conical tapered couplers on the external RI has been presented and it has been shown that it is possible to use such a structure to develop a fiber based refractometer [12], [13].…”

A fast-response microfiber coupler tip high temperature sensor

“…The sensor resolution R is defined as the minimum temperature change that the sensor can distinguish. Since the power resolution of the OSA (and commonly of many powermeters) is 10 -3 dB, an average R~0.66 ºC was achieved in the temperature range ~85.3 ºC to ~1511 ºC; this is higher than that obtained measuring the peak shift [11]. Better resolutions can be potentially achieved with smaller size MFCTs and signal processing.…”

“…In ref. [11], a compact thermometer based on a MFCT was reported: by measuring wavelength shifts, it measured a broad temperature interval ranging from room temperature to 1283 ºC with ~2.5 µm diameter tip. In this paper, a MFCT with minimum diameter of ~12.56 µm was chosen to ensure an adequate rigidity for the thermometer head and a wide temperature measurement range, even if this potentially resulted in multimode guidance.…”

“…In this paper, a MFCT with minimum diameter of ~12.56 µm was chosen to ensure an adequate rigidity for the thermometer head and a wide temperature measurement range, even if this potentially resulted in multimode guidance. The thermometer working principle was different from that used in ref [11]: instead of measuring a wavelength shift, the intensity change is recorded at a specific wavelength. Since the MFCT is made of silica, which softens at 1680 °C, it can potentially reach very high temperatures.…”

An investigation of the polarization dependence of a temperature sensor based on an optical microfiber coupler

“…Recently highly sensitive temperature sensors based on a full or half microfiber coupler (MFC) have been presented [6,7]. The maximum sensitivity of such sensors can reach circa 36.6 pm/°C, which is comparable to that achievable with the conventional optical fiber temperature sensors.…”