A method of improving the sensitivity of infrared to visible light conversion of temperature sensor based on Er3+ doped PLZT transparent ceramics

A high sensitivity temperature sensor based on the fluorescence intensity ratios, absorption cross section and the reflectivity of light has been investigated in Er3+ doped lead lanthanum zirconate titanate ceramics. The fluorescence intensity ratios (FIR) of two green upconversion emission peaks from different levels (H-2(11/2) and S-4(3/2)) to the ground state level were investigated for temperature performance from 313 K to 573 K when the sample was excited by a 980 nm diode laser with different incident light power, in which the sensitivity of the temperature sensor was also described as a function of temperature. Transmission spectra and absorption coefficient were measured in the same temperature range, which presented a good linear relationship with temperature and could be used as a temperature sensor. With the help of the helium-neon laser and power meter, the reflectivity and transmittance of the sample for a 632.8 nm light were measured, which showed a linear relationship with temperature in 3% Er3+ : PLZT, and could also be used in temperature sensing applications. This work provided a tool to determine the temperature using different ways (such as FIR, absorption coefficient, reflectivity, transmittance), it can greatly improve the sensitivity and credibility of temperature sensors.