Optical temperature probe
Optical temperature measurement technique utilizing phosphors
Thermometer with birefringent sensing element in fiber optic coupling
Semiconductor temperature sensor
Birefringent crystal thermometer
ApplicationNo. 06/257825 filed on 04/27/1981
US Classes:250/458.1, LUMINOPHOR IRRADIATION250/461.1, With ultraviolet source356/43, OPTICAL PYROMETERS356/44, With sample engaging rod or tube356/46, With incandescent standard374/121, By thermally emitted radiation374/127, Having significant frequency limitation or relationship (e.g., peak, ratio)374/128, Having significant signal handling circuitry (e.g., linearizing, emissivity compensation)374/129, Comparison with radiation reference standard374/131, With radiation conducting element374/143, Pressure73/700FLUID PRESSURE GAUGE
ExaminersPrimary: Willis, Davis L.
Attorney, Agent or Firm
International ClassesG01K 11/00 (20060101)
G01K 11/32 (20060101)
G01L 11/00 (20060101)
G01L 11/02 (20060101)
AbstractA photoluminescent indicator apparatus having automatic feedback means to maintain the sensitivity of the indicator apparatus with respect to variations in environmental conditions. The apparatus includes a sample of photoluminescent material having a photoluminescent decay rate which varies as a function of environmental conditions. The sample is positioned in a remote location having some unknown aspect of the environment desired to be measured. The sample is optically excited with a modulating signal to generate an excitation output signal functionally dependent on the modulating signal and indicative of the unknown environmental condition. A phase detection means is provided for comparing difference in phase between a phase reference signal and the excitation output signal to generate a phase differential signal functionally related to the photoluminescent decay rate of the sample. The indicator apparatus includes an automatic feedback means for adjusting the phase reference signal in accordance with the phase differential signal.