An up-conversion Ba3In(PO4)3:Er3+/Yb3+ phosphor that enables multi-mode temperature measurements and wide-gamut ‘temperature mapping’

Four modes of fluorescence temperature measurement were achieved by using a sample of Ba 3 In(PO 4 ) 3 :0.02Er 3+ /0.05Yb 3+ . As the temperature increased, the emission color of the sample changed from red to green, and highest S r value is 0.977% K −1 .