Photoluminescent temperature measurement system

Abstract

To solve the problem of a conventional temperature measurement device that a larger, expensive and complicated system is required for using separate detectors for temperature measurements and observation to identify a failure location.SOLUTION: Examples of a system and method for measuring a temperature and identifying a location of a failure in a temperature measurement system are disclosed. The system includes a light source and a detector mounted on a single substrate. When the system is in a temperature measurement mode, a driving circuit is providing a drive current pulse to the light source and a receiving circuit is receiving emitted light from a sensor. When an amplitude of the emitted light is within a predetermined threshold, a failure in the sensor or an optical path is identified. When the system is in an observation mode, a continuous drive current is provided to the light source so that the receiving circuit receives return light, and when the amplitude of the return light subtracted by the amplitude of the emitted light is within a predetermined threshold, a failure of the light source is identified.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates generally to photoluminescent thermometry systems, and more particularly to photoluminescent thermometry systems for temperature measurement and monitoring system efficiency for identifying fault locations. [Background technology]

[0002] Unless otherwise indicated herein, the material described in this section is not prior art to the claims in this application and is not admitted to be prior art by inclusion in this section.

[0003] A known photoluminescent temperature measurement system is a fiber optic temperature measurement system that uses the luminescence emitted from a sensing material (e.g., a phosphor) to determine the temperature of an object in contact with the sensing material. Typically, a thermographic phosphor emits light in a different wavelength range when excited by light in a particular wavelength range. Certain characteristics of the emitted light, including brightness, color, and duration of afterglow, vary with temperature. The response of the emitted light to temperature is observed by various methods, such as analyzing the change in emission intensity in a single wavelength range or the change in the intensity ratio of two or more wavelength ranges, lifetime decay, or shift in emission wavelength peak. The phosphor used to measure the temperature of an object is either directly coated on the surface of the object or placed in a probe in contact with the surface, which is then illuminated by a light source, and the temperature of the object is determined based on the response of the emitted light.

[0004] A typical fiber optic temperature measurement system known in the prior art includes a fiber optic probe with an active sensing material at its tip, which can be coupled with optoelectronics to process the detected signal. Particularly in the semiconductor industry, failure of the optoelectronics of a fiber optic temperature sensor is often associated with major downtime and costs of production. The most common failures of the optoelectronic transducer are failure of the excitation light source (failure of an LED (light emitting diode)), failure in the sensor, or failure in the optical path (i.e. damage to the fiber optic probe). When a failure occurs, the manufacturing process needs to be interrupted to replace the failed optoelectronic transducer.

[0005] A separate observation system is used to identify the location of the fault, for example, US Patent Application Publication No. 20090296770 discloses a temperature measurement device that uses separate detectors for temperature measurement and observation to identify the fault location, making the system larger, more expensive and cumbersome. [Brief description of the drawings]

[0006] Throughout the drawings, reference numbers may be reused to indicate correspondence between referenced elements. The drawings are provided to illustrate example embodiments described herein and are not intended to limit the scope of the present disclosure. The sizes and relative positions of components in the drawings are not necessarily drawn to scale. For example, the shapes and angles of various components are not drawn to scale, and some of these components are arbitrarily enlarged and positioned to improve the visibility of the drawings.

[0007] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of a photoluminescent temperature measurement system of the present invention. [Diagram 2]FIG. 2 is a schematic partial diagram illustrating an example of a photoluminescent temperature measurement system showing a substrate with two light sources and two detectors. [Diagram 3] FIG. 1 is a schematic partial view of an example of a photoluminescent temperature measurement system showing a substrate with a light source and detector connected to a fiber optic probe. [Figure 4] 1 is a flow chart illustrating a method for temperature measurement and observation of system efficiency to identify fault locations. Summary of the Invention [Means for solving the problem]

[0008] In one embodiment, a photoluminescent temperature measurement system for temperature measurement and observation to identify system faults is provided. The photoluminescent temperature measurement system includes a fiber optic probe having a fiber bundle for transmitting excitation light to the active material of the sensor and transmitting return light from the sensor. The system further includes an optoelectronic module coupled to a first end of the fiber optic probe. The optoelectronic module includes a light source mounted on a substrate to provide excitation light to the sensor, a detector mounted on the substrate proximate to the light source to detect light returning from the sensor, a drive circuit having a switch for providing a drive current to the light source, a receiver circuit coupled to the detector, and a processor coupled to the drive circuit and the receiver circuit. The drive circuit provides drive current pulses to the light source when the system is in a temperature measurement mode and provides a continuous direct current to the light source when the system is in an observation mode. The receiver circuit receives the emitted light emitted from the active material of the sensor after the light source is turned off when the system is in a temperature measurement mode and receives the light reflected back to the detector when the light source is driven by a continuous direct current during the observation mode. The processor is preprogrammed to calculate an amplitude value of the light emitted from the active material of the sensor after the light source is turned off during a temperature measurement mode to determine the temperature in the environment based on a change in radiation intensity in a single wavelength range of the emitted light or a change in the intensity ratio of two or more wavelength ranges, a lifetime decay, or a shift in the emission wavelength peak, and to calculate an amplitude value of the reflected light during an observation mode and determine the efficiency of the light source by subtracting the calculated amplitude of the emitted light, thereby identifying a failure of the active material / fiber probe if the calculated amplitude value of the emitted light is within a predetermined emission light amplitude threshold range and identifying a failure of the light source if the calculated efficiency of the light source is within a predetermined light source efficiency threshold range.

[0009] In another aspect, a method is provided for determining the temperature of an environment and locating a fault in a temperature measurement system. The method includes providing a drive current pulse to a light source coupled to a substrate to provide excitation light to a sensor having an active material, detecting the emitted light emitted from the sensor after the light source is turned off with a detector coupled to the substrate proximate the light source, and calculating the amplitude of the emitted light to determine the amplitude of the signal power of the emitted light, thereby identifying a fault in the sensor or fiber optic probe if the amplitude of the emitted light from the sensor is within a predetermined threshold range. The method further includes providing a continuous DC drive current to the light source while the light source is turned on to detect the returned light, calculating the amplitude of the returned light and determining the efficiency of the light source by subtracting the amplitude of the emitted light from the amplitude of the returned light, thereby identifying a fault in the light source if the efficiency of the light source is within a predetermined threshold range. If no fault is identified, the temperature of the environment adjacent to the sensor is determined based on a change in the radiant intensity in a single wavelength range or a change in the intensity ratio of two or more wavelength ranges of the emitted light during the temperature measurement mode, a lifetime decay, or a shift in the emission wavelength peak.

[0010] In addition to the aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following detailed descriptions. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Typically, photoluminescent temperature measurement systems have temperature measurement and fault monitoring systems that are separated from each other, which may require separate detectors and optical paths, and in some implementations may require collimating lenses, focusing lenses, mirrors, or filters, which increase the size and complexity / cost of the measurement device. The present invention discloses a temperature measurement system that allows for a smaller and more economical version of the sensing module by eliminating optical lenses, filters, or mirrors, while also monitoring the "health" of the system to identify any system degradation or system failure, the location of such degradation / failure, and thus warn the user in advance if preventive maintenance is required.

[0012] 1 illustrates an example of a photoluminescent temperature measurement system 10 that includes a fiber optic probe 12 having a fiber bundle 14 for transmitting excitation light to an active material of a sensor 16 and transmitting light back from the sensor 16. The fiber optic probe 12 has a first end 11 and a second end 13. The sensor 16 may be coupled to the second end 13 such that light excites an active material in the sensor 16 as the light is transmitted through the fiber bundle 14 to make a temperature measurement in an environment / object 18 proximate to the sensor 16. In one embodiment, the sensor 16 may be coupled to the object / environment in which the temperature measurement is to be made such that the second end 13 of the fiber optic probe 12 is proximate to the sensor during the measurement.

[0013] An optoelectronic module 20 is connected to the first end 11 of the fiber probe 12. The optoelectronic module 20 includes a light source 22 mounted on a substrate 23 to provide excitation light to the sensor 16, and a detector 24 also mounted on the substrate 23 proximate to the light source 22 to detect light returning from the sensor 16. The light source 22 is aligned with the fiber bundle 14 such that the excitation light is received and transmitted to the active material of the sensor 16. The detector 24 is also aligned with the fiber bundle 14 such that light emitted from the active material of the sensor 16 is transmitted to the detector 24. The fiber bundle 14 may transmit both excitation light and emission light. The fiber bundle 14 may include multiple optical fibers arranged in a parallel configuration within the fiber bundle 14, or may be a single fiber bundle core. The fiber bundle core may be a glass or polymer (plastic) optical fiber(s). In one implementation, a fiber bundle splitter may be provided to split a single fiber bundle 14 into an excitation light guide and an emission light guide, allowing a portion of the fiber bundle 14 to be used as a path to deliver excitation light to the sensor 16 and the remaining portion of the fiber bundle 14 to direct emission light back to the detector 24. The integration of a fiber bundle splitter may replace the free space optical splitter used in prior devices, thus significantly reducing the size of the optoelectronics. In addition, placing the light source 22 and the detector 24 close to each other on a single substrate 23 further minimizes the size of the system 10. In one embodiment, the fiber bundle 14 may include a separate excitation light guide aligned with the light source 22 and an emission light guide aligned with the detector 24.

[0014] The light source 22 may be a laser or LED configured to provide excitation light in the blue to green wavelength range (e.g., 350-550 nm). In one embodiment, the light source 22 may provide excitation light in the UV wavelength range between 200-400 nm. A driver circuit 26 having a switch 25 is coupled to the light source 22 to activate the light source. The driver circuit 26 may have a first temperature measurement mode and a second system monitoring mode. During the temperature measurement mode, the driver circuit 26 provides a drive current pulse to the light source 22 to provide excitation light to the sensor 16 to excite the active material. For example, the drive current pulse during the temperature measurement mode may be 1 ms to 100 ms. During the monitoring mode, the driver circuit 26 provides a continuous direct current to the light source 22 such that the light source 22 is turned on during the monitoring mode. The drive current may be in the range of 1 μA to 100 mA.

[0015] The detector 24 is configured to receive light emitted from the sensor 16 when the light source (e.g., LED) is turned off during the temperature measurement mode, and to receive the returning (reflected) light detected when the light source 22 is still on and illuminating the sensor 16 during the observation mode. In one implementation, the detector 24 can be a photodiode. The photodiode 24 can convert the light signal (emitted / reflected light) into an analog electrical signal. Photons absorbed by the photodetector 24 (e.g., photodiode) generate an electrical current. In one implementation, an amplifier (not shown) can be used to enhance the electrical signal, and then an A / D converter (not shown) can be used to digitize the analog electrical signal. In an alternative embodiment, the detector 24 can include multiple LEDs for detecting emitted light. That is, these multiple LEDs are semiconductor PN junctions (positive and negative doped semiconductors, such as silicon) that can detect incident light by generating a photocurrent, similar to a photodiode.

[0016] The receiver circuit 28 is coupled to the detector 24. When the system is in a temperature measurement mode, the receiver circuit 28 receives the emitted light emitted from the active material of the sensor 16 after the light source 22 is turned off. During an observation mode, the receiver circuit 28 receives light reflected from the sensor 16 towards the detector 24 while the light source 22 is still turned on.

[0017] The optoelectronic module 20 further includes a processor 29 coupled to the driver circuit 26 and the receiver circuit 28. The processor 29 is preprogrammed to calculate an amplitude value of the light emitted from the active material of the sensor 16 after the drive current pulse is completed and the light source 22 is turned off. Based on the amplitude value of the emitted light, the processor 29 determines whether there is a failure of the sensor 16 (e.g., degradation of the active material) or a failure / damage of the optical path of the fiber probe 12 (e.g., damage to the fiber bundle 14). If the amplitude of the emitted light is within a predefined range of the amplitude threshold of the emitted light, a fault in the sensor 16 or the optical path (fiber probe 12) is identified and a warning signal is sent to the user. The predefined amplitude threshold of the emitted light can be set within a range of 0-100 μW, and a fault is identified if the amplitude of the emitted light is within this range. If the amplitude of the emitted light is greater than the 100 μW threshold, a fault in the sensor / optical path is not identified. The processor 29 further determines the efficiency of the light source 22 by calculating the amplitude value of the reflected light when the light source 22 is driven by a continuous drive current during the observation mode, and subtracting the calculated amplitude of the emitted light from the amplitude of the reflected light. When the calculated efficiency of the light source 22 is within a predetermined illuminance efficiency threshold range, a fault of the light source 22 is identified and a warning signal is sent to the user. The predetermined illuminance efficiency threshold can be set, for example, within a range of 0 to 1 mW.

[0018] If no fault in the system 10 is identified, the temperature in the environment is determined by the processor 29 based on a change in the radiation intensity in a single wavelength range of the emitted light or a change in the intensity ratio of two or more wavelength ranges, lifetime decay, or a shift in the emission wavelength peak during the temperature measurement mode.

[0019] The processor 29 may further include a non-volatile memory having configuration and calibration data for the fiber optic probe 12 and the active sensing material 16. The optoelectronics module 20 may further include communication circuitry (not shown) that may communicate with a power source and any other additional external data processing units.

[0020] The photoluminescent temperature measurement system 10 may further include a user interface 30 for informing a user of the measured temperature and / or identified fault location. The user interface 30 may be a digital user interface in communication with the processor 29, such as a human-machine interface (HMI) for connecting a user interface or dashboard with the system 10 for visually displaying the measured temperature data and / or fault location or for tracking trends in system degradation. The user interface 30 may further communicate with a proportional integral derivative (PID) controller, an industrial controller, a sensing network distributor, or the like, may be part of a distributed sensing network around the semiconductor tool, or may be integrated into a data aggregator for monitoring purposes. The user interface 30 may include a display for displaying the measured temperature and / or identified fault location, and may further include an audio component for providing an audio massage of the measured temperature and / or identified fault location.

[0021] In one embodiment shown in FIG. 2, the light source 22 can be multiple light sources, such as multiple LEDs as a cluster. For example, the light source 22 can include two or more light sources (LEDs) that can be redundant excitation sources in case the main LED fails. In the example shown in FIG. 2, there can be two LEDs 22 and two photodiodes 24. The close cluster arrangement of multiple light sources 22 and / or detectors 24 allows for a splitterless design of the system 10. Multiple light sources 22 (e.g., LEDs) allow the system 10 to provide excitation light at different wavelengths to address different active materials for a particular temperature range and photoluminescent material. In one embodiment, multiple light sources 22 can be used to have multiple redundant excitation sources, so that if a light source 22 fails, the processor 29 of the system 10 can detect the failure of the light source and deploy a backup light source. Before deploying redundant light sources, the light source efficiency is monitored and the user is alerted if the degradation level reaches a predefined threshold. In one embodiment, the light source 22 can be a flip chip LED with multiple LEDs in close proximity forming a tight cluster that can be coupled into the optical fiber core port / path using the same optics as when a single LED is used. In another embodiment, redundant active components (LEDs) are free space optically coupled in the same optical path using cold mirrors and lenses and focused at the same optical port, e.g., the same fiber core, e.g., 1 μA to 500 mA. Figure 2 shows a 1.5 mm diameter polymer optical fiber (POF) optical fiber core 32 coupled to two LEDs 22 and two photodiodes 24.

[0022] 3 partially illustrates a photoluminescent temperature measurement system 10 having a fiber optic probe 12 coupled to a substrate 23 having a light source 22 and a detector 24. The system may include a single LED 22 and / or a cluster of two or more LEDs, and the detector 24 may include a single photodiode or a cluster of two or more photodiodes. A connector 34 is configured to connect an optoelectronic module 20 (which aligns the light source 22 and detector 24 with the fiber bundle 14) with the fiber optic probe 12.

[0023] FIG. 4 shows a flow chart of a method for temperature measurement and observation of system efficiency to identify fault location. The method includes switching on the drive circuit 26 to drive the light source 22 for a current pulse of 1 ms to 100 ms. The drive current can be in the range of 1 μA to 100 mA. When the drive current pulse ends and the light source 22 is turned off, the detector 24 collects the raw attenuation signal (emitted light) from the sensor 16 over a period of 1 ms to 100 ms (e.g., four integral windows over a period of 1 ms to 100 ms), calculates (with the processor 29) Tou (the attenuation of the signal coming from the sensor 16) and the amplitude A0 of the emitted light at time 0 after the light source 22 is turned off, and determines the amplitude of the emitted light signal power returning from the active material of the sensor 16. The light source 22 is then driven by a drive current of 1 μA to 100 mA by switching on the drive circuit 26 using the switch 25. While keeping the light source 22 on, the raw signal of the returned light (reflected light) is detected by the photodiode 24 and the amplitude of the power of the returned light is calculated by the processor 29. The calculated amplitude of the returned light power determines the combination of the optical power output of the light source 22 and the output of the active material, so that the efficiency of the light source 22 is determined by subtracting the calculated amplitude of the emitted light after the drive current pulse from the calculated amplitude when the light source is on. If the efficiency of the light source 22 is within a threshold range, for example, 0 to 1 mW, a light source failure is identified and a warning signal is sent to the user using the user interface 30. If the efficiency of the light source 22 is higher than a threshold, for example, 1 mW, no LED failure is identified. Based on the amplitude of the emitted light signal power, the efficiency of the sensor 16 and the optical path (for example, the efficiency of the fiber probe 12) is determined. For example, if the amplitude of the emitted light signal power is within a threshold range, for example, 0 to 100 μW, a failure in the sensor 16 or the fiber probe 12 is identified.If the amplitude of the emitted light signal power is greater than 100 μW, there is no failure of the sensor 16 or fiber probe 12, and the temperature of the environment can be determined based on the change in radiation intensity in a single wavelength range or the change in the intensity ratio of two or more wavelength ranges of the emitted light from the active material during the temperature measurement mode, the lifetime decay, or the shift in the emission wavelength peak.

[0024] In one implementation, the active material may be a thermographic phosphor, which when illuminated with an excitation light, emits light at a different wavelength than the excitation light. For example, the excitation light may be UV light having a wavelength of 200-400 nm, or light in the blue to green wavelength range (e.g., 350-550 nm). When the active material is illuminated with such an excitation light, it will emit fluorescence in the red wavelength range of 600-800 nm. The response of the emitted light to temperature is observed by various methods, such as by analyzing the change in emission intensity in a single wavelength range or the change in the intensity ratio of two or more wavelength ranges, lifetime decay, or shift in emission wavelength peak.

[0025] Although specific components, embodiments, and applications of the present disclosure have been shown and described, it will be understood that the scope of the present disclosure is not limited thereto. Because modifications may be made by those skilled in the art without departing from the scope of the present disclosure, especially in light of the foregoing teachings. Thus, for example, in any method or process disclosed herein, the activities or operations making up the method / process may be performed in any suitable order, and are not necessarily limited to any particular order disclosed. In various embodiments, the elements and components may be configured or arranged in different ways, combined, and / or removed. The various features and processes described above may be used independently of each other or combined in various ways. All possible combinations and subcombinations are intended to be within the scope of this disclosure. References to "some embodiments" or "embodiments" and the like throughout this disclosure mean that a particular feature, structure, step, process, or characteristic described in connection with that embodiment is included in at least one embodiment. Thus, the appearance of phrases such as "in some embodiments" or "in embodiments" throughout this disclosure do not necessarily all refer to the same embodiment, but may refer to one or more of the same or different embodiments.

[0026] Various aspects and advantages of the embodiments are described where appropriate. It should be understood that not all such aspects or advantages may be achieved by any particular embodiment. Thus, for example, it should be recognized that various embodiments may be implemented in a manner that achieves or optimizes one advantage or group of advantages taught herein, while not necessarily achieving other aspects or advantages that may be taught or suggested herein.

[0027] Conditional language used herein, such as, inter alia, "can, could," "might, may," "eg," and the like, is generally intended to convey that a particular embodiment includes certain features, components, and / or steps, whereas other embodiments do not, unless otherwise specifically stated or understood in the context of use. Thus, such conditional language is generally not intended to imply that the features, components, and / or steps are required in any manner for one or more embodiments, or that one or more embodiments necessarily include logic for determining whether those features, components, and / or steps are included or performed in any particular embodiment, with or without operator input or direction. No single feature or group of features is required or essential to any particular embodiment. Terms such as "comprising," "having," and the like are synonymous and used inclusively in an open-ended manner and do not exclude additional components, features, activities, operations, and the like. Also, the term "or" is used in an inclusive sense (and not an exclusive sense), so that, for example, when used to connect a list of components, the term "or" means one, some, or all of the components in that list.

[0028] The example calculations, simulations, results, graphs, values, and parameters of the embodiments described herein are intended to illustrate, but not limit, the disclosed embodiments. Other embodiments may be configured and / or operate differently than the illustrative examples described herein.

Claims

1. 1. A photoluminescent temperature measurement system, comprising: a. a fiber optic probe having a fiber bundle having a first end and a second end; b) a sensor having an active material coupled to the second end of the fiber optic probe, the fiber bundle configured to transmit excitation light to the active material of the sensor and transmit light back from the sensor, the active material emitting light of a different wavelength than the excitation light when illuminated by the excitation light; c. an optoelectronics module coupled to the first end of the fiber optic probe, the optoelectronics module comprising: i. a light source mounted on the substrate to provide the excitation light to the sensor; ii. a detector mounted on the substrate proximate to the light source for detecting the returning light from the sensor; iii. A drive circuit coupled to the light source and having a switch for providing a drive current to the light source, the drive circuit comprising:

1. providing a drive current pulse to the light source when the system is in a temperature measurement mode; 2. A driver circuit that provides continuous direct current to the light source when the system is in an observation mode; iv. a receiver circuit coupled to the detector for receiving radiated light emitted from the active material of the sensor after the light source is turned off when the system is in the temperature measurement mode and light reflected towards the detector when the light source is driven by the continuous direct current when the system is in the observation mode; v. a processor coupled to the driver circuit and the receiver circuit, the processor being preprogrammed to: calculate an amplitude value of light emitted from the active material of the sensor after the light source is turned off; and determine an efficiency of the light source by calculating an amplitude value of the reflected light during the observation mode and subtracting the calculated amplitude of the emitted light; A photoluminescent temperature measurement system, wherein an active material / fiber probe failure is identified if the calculated emitted light amplitude value is within a predetermined emitted light amplitude threshold range, a light source failure is identified if the calculated efficiency of the light source is within a predetermined light source efficiency threshold range, and if no failure is identified, the processor determines a temperature of the environment based on a change in radiant intensity in a single wavelength range of the emitted light or a change in the intensity ratio of two or more wavelength ranges, a lifetime decay, or a shift in the emission wavelength peak during the temperature measurement mode.

2. The photoluminescent temperature measurement system of claim 1 , wherein the predetermined luminous efficacy threshold is settable within a range of 0 to 1 mW.

3. 2. The photoluminescent temperature measurement system of claim 1, wherein the predetermined emitted light amplitude threshold is settable within a range of 0 to 100 μW.

4. The photoluminescent temperature measurement system of claim 1 , wherein the fiber bundle comprises one or more glass fibers or one or more polymer optical fibers.

5. The photoluminescent temperature measurement system of claim 1 , further comprising a connector for connecting said optoelectronic module to said fiber optic probe.

6. 2. The photoluminescent temperature measurement system of claim 1, wherein the drive current pulse during the temperature measurement mode has a duration of 1 ms to 100 ms.

7. The photoluminescent temperature measurement system of claim 1 , wherein the light source is a laser diode.

8. The photoluminescent temperature measurement system of claim 1 , wherein the light source is a light emitting diode (LED).

9. The photoluminescent temperature measurement system of claim 1 , wherein the light source comprises two or more redundant light sources.

10. The photoluminescent temperature measurement system of claim 9 , wherein the light source is a cluster of LEDs.

11. The photoluminescent thermometry system of claim 10 , wherein when a failure of an excitation light source is detected, the processor switches to one of the redundant light sources.

12. The photoluminescent temperature measurement system of claim 1 , wherein the light source provides excitation light in the wavelength range of 350 to 550 nm.

13. The photoluminescent temperature measurement system of claim 10 , wherein the detector is a cluster of multiple detectors.

14. 2. The photoluminescent temperature measurement system of claim 1, wherein the fiber bundle includes a light guide operatively coupled to the light source and the detector for delivering the excitation light to the active material and transmitting emitted light and reflected light to the detector.

15. 2. The photoluminescent temperature measurement system of claim 1, wherein the drive current is in the range of 1 μA to 100 mA.

16. 13. The photoluminescent temperature measurement system of claim 1, further comprising a user interface, the user interface being a digital human-machine interface (HMI) that communicates with the processor to visually display measured temperature data and / or fault locations or track trends in system degradation.

17. The photoluminescent temperature measurement system of claim 16 , wherein the user interface includes a display for displaying the measured temperature and / or the identified fault location.

18. 20. The photoluminescent temperature measurement system of claim 17, wherein the user interface is in communication with a proportional-integral-derivative (PID) controller, an industrial controller, or a sensing network distributor, is part of a distributed sensing network around a semiconductor tool, or is integrated into a data aggregator for observation purposes.

19. 1. A method for determining the temperature of an environment and locating a fault in a temperature measurement system, the method comprising: a. In temperature measurement mode: i. providing a drive current pulse to a light source coupled to the substrate to provide excitation light to a sensor having an active material coupled to a second end of a fiber optic probe; ii. detecting radiation emitted from the sensor after the light source is turned off using a detector coupled to the substrate proximate to the light source; iii. calculating an amplitude of the emitted light to determine an amplitude of a signal power of the emitted light, wherein a fault in the sensor or the fiber optic probe is identified when the amplitude of the emitted light from the sensor is within a predetermined threshold range; b. In the observation mode, i. providing a continuous DC drive current to said light source and detecting returning light while said light source is provided with said continuous drive current; ii. determining the efficiency of the light source by calculating the amplitude of the returning light and subtracting the amplitude of the emitted light from the returning light, wherein a fault in the light source is identified if the efficiency of the light source is within a predetermined threshold range; and c) if no fault is identified, determining a temperature of an environment adjacent to said sensor based on a change in radiation intensity in a single wavelength range or a change in the intensity ratio of two or more wavelength ranges of said emitted light, a lifetime decay, or a shift in emission wavelength peak during said temperature measurement mode.

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