Multi-characteristic optical temperature sensor

Abstract

This application discloses an embodiment of a temperature sensor system for determining the temperature of an object using multiple characteristics of an optical emission signal. The temperature sensor system includes a light source configured to emit an optical excitation signal that propagates to a temperature probe having a phosphorescent sensing element that emits an optical excitation response signal having the characteristics of phosphorescent emission proportional to the temperature of the object. The temperature probe emits an optical excitation-independent signal having the characteristics of blackbody emission emitted by the components of the temperature probe. The optical excitation response signal and the optical excitation-independent signal form a composite signal that propagates to a detector that provides a controller with a signal representing the composite signal. The controller is configured to separate the signal representing the composite signal into signals representing the optical excitation response signal and the optical excitation-independent signal, and to calculate the temperature of the object.

Description

[Technical Field]

[0001] Cross-references to related applications This application claims priority to U.S. Patent Application No. 18 / 341,395, titled "Multiple Characteristic Optical Sensor," filed on 26 June 2023, the contents of which are incorporated herein by reference. [Background technology]

[0002] background Optical sensors, particularly fiber optic sensors, are used in a variety of semiconductor manufacturing applications, including measuring the temperature, strain, and position of wafers, electrostatic chucks, showerheads, and other components in radio frequency environments with highly irritating chemicals inside and around wafer processing chambers, other radio frequency high-energy environments, and nuclear magnetic resonance imaging. Optical sensors have the advantage of being unaffected by radio frequency energy and high magnetic fields. Another advantage is the opportunity to physically isolate the sensing element from other elements of the temperature measurement system, for example, to enable the characterization of extremely hot objects or moving / rotating objects such as turbine blades, or to reduce the influence of the measurement system on the object or system to be measured, such as thermal effects.

[0003] One type of optical temperature sensor system is a thermographic phosphorescent temperature sensor that determines temperature by measuring one or more temperature-dependent characteristics of a phosphorescent material or emission from a phosphorescent material, such as a temperature-dependent variation in the decay time constant of the phosphorescent emission (also referred to herein as the “time constant”), or a temperature-dependent variation in the intensity of the temperature-dependent variation, or other temperature-dependent parameters for determining the temperature. These thermographic sensor systems typically use an optical pump, such as an LED, laser, or other light source, to excite a phosphorescent sensing element, and the resulting phosphorescent emission is measured by a photodetector. The optical path (e.g., optical fiber or optical waveguide) is positioned to be thermally connected to a target surface, target object, or optically connected to a phosphorescent material that is immersed in the measurement location where temperature measurement is required. The resulting phosphorescent emission is coupled back into the waveguide, guided within the waveguide to a photodetector, and analyzed to determine the temperature of the target surface, target object, etc.

[0004] Conventional thermographic phosphorescent temperature sensors and sensor systems have been considered useful, but several drawbacks have also been pointed out. For example, blackbody radiation emitted from the surface of the components of these sensors can couple with the phosphorescent radiation signal in the optical waveguide, potentially interfering with or affecting the phosphorescent radiation signal, the measurement signal, or the result. What is needed is a measurement system that can distinguish between phosphorescent radiation and blackbody radiation and use both signals to accurately measure temperature over a wider temperature range, especially at temperatures where the blackbody radiation signal is significantly greater than the phosphorescent radiation signal. [Overview of the project]

[0005] overview This application discloses various embodiments of a temperature sensor system for determining the temperature of an object using multiple characteristics of an optical emission signal. In one embodiment, the temperature sensor system comprises at least one light source configured to emit at least one photoexcitation signal, and at least one temperature sensing device including at least one sensing element thermally connected to at least one object to be measured, wherein the sensing element is configured to emit at least one photoexcitation response signal, and the temperature sensing device is configured to emit at least one first composite signal including at least a portion of the photoexcitation response signal and at least one photoexcitation-independent signal. The temperature sensor system further comprises at least one first detector configured to receive at least a portion of the at least one first composite signal, and at least one optical path configured to allow the photoexcitation signal to propagate to the sensing element and at least a portion of the first composite signal to propagate from the temperature sensing device to the first detector. At least one controller is provided, and the first detector is configured to provide the controller with at least one signal representing the first composite signal, and the controller is configured to separate the signal representing the first composite signal into at least one signal representing the photoexcitation response signal and at least one signal representing the photoexcitation-independent signal. The controller is configured to calculate the object temperature based on at least one of the signal representing the photoexcitation response signal and the signal representing the photoexcitation-independent signal. The signal representing the photoexcitation-independent signal includes at least one first characteristic of the signal representing the photoexcitation-independent signal, and the signal representing the photoexcitation response signal includes at least one second characteristic of the signal representing the photoexcitation response signal. In various embodiments, at least one of the first characteristic or the second characteristic includes at least one of intensity or amplitude, change in intensity or amplitude over a period of time, intensity decay rate, optical power spectrum, or one or more portions of the optical power spectrum. The controller described above is configured to calculate the object temperature based on at least one of the first characteristics of the signal representing the photo-excitation-independent signal and the second characteristics of the signal representing the photo-excitation response signal.In various embodiments, the first characteristic of the signal representing the photo-excitation-independent signal may include the intensity of blackbody radiation or the intensity of blackbody radiation at at least one wavelength. In various embodiments, the second characteristic of the signal representing the photo-excitation response signal may include the intensity decay rate of the photo-excitation response signal or the intensity of the photo-excitation response signal at at least one wavelength. In one embodiment, the temperature sensor system further comprises a temperature transition range, and the controller is configured to determine the object temperature when the object temperature is below the temperature transition range using the photo-excitation response signal, and to determine the object temperature when the object temperature is above the temperature transition range using the photo-excitation-independent signal. The object temperature from the photo-excitation-independent signal may be used to determine whether the object temperature is above or below the temperature transition range. In one embodiment, the controller is configured to use the photo-excitation response signal to determine the object temperature when the object temperature is lower than the minimum value of the temperature transition range, and to use the photo-excitation-independent signal to determine the object temperature when the object temperature is higher than the maximum value of the temperature transition range, and to use a combination of the photo-excitation response signal and the photo-excitation-independent signal when the object temperature is within the temperature transition range. In one embodiment, the temperature sensor system may further include at least one second detector configured to receive at least a portion of the first composite signal, the optical path configured so that the first portion of the composite signal can propagate to the first detector and the second portion of the composite signal can propagate to the second detector, at least a portion of the first portion of the composite signal includes the photo-excitation response signal and at least a portion of the second portion of the composite signal includes the photo-excitation-independent signal.

[0006] In other embodiments, the temperature sensor system comprises at least one light source configured to emit at least one photoexcitation signal, and at least one temperature sensing device including at least one sensing element thermally connected to at least one object to be measured. The sensing element is configured to emit at least one photoexcitation response signal, and the temperature sensing device is configured to emit at least one first composite signal including at least a portion of the photoexcitation response signal and at least one photoexcitation-independent signal. The temperature sensor system further comprises an optical analysis module configured to receive at least a portion of the first composite signal. The temperature sensing system may further comprise at least one optical path configured to allow the photoexcitation signal to propagate to the sensing element and at least a portion of the first composite signal to propagate from the temperature sensing device to the optical analysis module. The optical analysis module receives the composite signal from the temperature sensing device and is configured to separate the composite signal into a plurality of distinct wavelength components that propagate to at least one measuring module including a plurality of detectors. Each of the above-mentioned detectors corresponds to each of the above-mentioned distinct wavelength components and is configured to provide the controller with at least one signal representing each of the above-mentioned distinct wavelength components. The controller is configured to separate the signal representing each of the above-mentioned distinct wavelength components into at least one signal representing the photoexcitation response signal and at least one signal representing the photoexcitation-independent signal.

[0007] In other embodiments, the temperature sensor system includes at least one light source configured to emit at least one photoexcitation signal, and at least one temperature sensing device having at least one sensing element thermally connected to the object being measured. The sensing element is configured to emit at least one photoexcitation response signal. The temperature sensing device may be configured to emit at least one first composite signal comprising at least a portion of the photoexcitation response signal and at least one photoexcitation-independent signal. The temperature sensor system further includes at least one first detector configured to receive at least a portion of the first composite signal, and at least one optical path configured to allow the photoexcitation signal to propagate to the sensing element and at least a portion of the first composite signal to propagate from the temperature sensing device to the first detector. The temperature sensor system described above is configured to determine at least one signal representing the photo-excitation-independent signal at a first time, determine at least one signal representing the photo-excitation response signal at a second time different from the first time, and calculate the object temperature based on at least one of the signal representing the photo-excitation-independent signal determined at the first time and the signal representing the photo-excitation response signal determined at the second time. The signal representing the photo-excitation-independent signal at the first time includes at least one first characteristic of the signal representing the photo-excitation-independent signal at the first time, and the signal representing the photo-excitation response signal at the second time includes at least one second characteristic of the signal representing the photo-excitation response signal at the second time. In various embodiments, the first characteristic of the signal representing the photo-excitation-independent signal at the first time may include the intensity of blackbody radiation or the intensity of blackbody radiation at at least one wavelength. The temperature sensor system may further include a first temperature measuring device configured to measure the temperature of the detector. The temperature of the detector is used at least partially to determine the dark current of the detector, and the object temperature is determined at least partially by making a correction to the dark current of the detector. [Brief explanation of the drawing]

[0008] Brief explanation of the drawing Various embodiments of an improved temperature measurement system are described in more detail by the accompanying drawings.

[0009] [Figure 1] FIG. 1 shows a graph of the optical power spectrum of blackbody radiation as a function of temperature, according to Planck's law.

[0010] [Figure 2] FIG. 2 shows a schematic cross-sectional view of an exemplary embodiment of a portion of an optical fiber temperature probe for measuring the temperature of an object using a thermographic phosphor and / or blackbody radiation.

[0011] [Figure 3] FIG. 3 shows a schematic cross-sectional view of an exemplary embodiment of a portion of an optical fiber temperature probe for measuring the temperature of an object using a sensing material having a temperature-sensitive bandgap and blackbody radiation.

[0012] [Figure 4] FIG. 4 shows the optical power spectra of a thermographic phosphor and a blackbody at various temperatures.

[0013] [Figure 5] FIG. 5 shows a schematic diagram of an exemplary embodiment of a temperature sensor system.

[0014] [Figure 6] FIG. 6 shows a schematic diagram of another embodiment of a temperature sensor system.

[0015] [Figure 7] FIG. 7 shows a schematic diagram of another embodiment of a temperature sensor system.

[0016] [Figure 8] FIG. 8 shows a timing diagram of an operational embodiment of a temperature sensor system.

[0017] [Figure 9] Figure 9 shows a timing diagram of another operational embodiment of the temperature sensor system.

[0018] [Figure 10] Figure 10 shows a flowchart of an exemplary embodiment of a measurement method that operates to measure an object temperature using an exemplary embodiment of the temperature sensor system.

[0019] [Figure 11] Figure 11 shows a graph of an exemplary embodiment of a weight function over a temperature transition range.

BEST MODE FOR CARRYING OUT THE INVENTION

[0020] Detailed explanation Examples of embodiments will be described below with reference to the accompanying drawings. Unless explicitly stated, in the drawings, the sizes, positions, and distances between components, features, elements, etc. are not necessarily to scale and may be exaggerated for ease of understanding. Similarly, the values and periods shown in the figures (e.g., graphs of signal strength over time) are not necessarily to scale. In the drawings, the same numerals mean the same elements. For this reason, even if the same or similar numerals are not referred to or described in the corresponding drawings, they may be described by referring to other drawings. Also, elements without reference numerals may be described by referring to other drawings.

[0021] The terms used in this specification are for illustrative purposes only and are not intended to limit any particular embodiment. Unless otherwise specifically defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art. Where used herein, singular nouns are intended to include plural nouns unless the context explicitly indicates otherwise. The terms “at least one,” “at least,” and “one or more” are intended to include both singular and plural nouns, depending on the context. Furthermore, the terms “equipped with” and / or “equipped with” identify the presence of a described feature, integer, step, action, element, and / or component, but should be understood not to exclude the presence or addition of one or more other features, integers, steps, actions, elements, components, and / or groups thereof. Unless otherwise specifically indicated, terms such as “first” and “second” are used solely to distinguish elements from one another. For example, one fitting may be called the “first fitting,” and another fitting may be called the “second fitting,” and vice versa.

[0022] Unless otherwise specified, spatially relative terms such as “downward,” “below,” “underside,” “upward,” and “opposite side” may be used herein to facilitate explanation when describing the relationship between one element or feature and another, as shown in the figures. It should be understood that spatially relative terms are intended to include orientations other than those shown in the figures. For example, an element described as being “downward” or “below” another element or feature would face “upward” of the other element or feature if the object in the figure were inverted. Thus, the term “downward” may include both upward and downward orientations. Objects may also be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein may be interpreted accordingly. A set of reference axes (e.g., X, Y, Z), directions, or coordinates, and rotations around them (e.g., θX, θY, θZ) may be included in the figures to facilitate the reader's understanding of the figures and the specification, but this does not necessarily indicate that a particular feature or element is aligned with or orthogonal to other features or elements.

[0023] Paragraph numbers used herein are for organizational purposes only, unless otherwise specified, and should not be construed as limiting the subject matter discussed. It will be understood that many different forms, embodiments, and combinations are conceivable without departing from the spirit and teachings of this disclosure, and that this disclosure should not be construed as limiting to the examples of embodiments described herein. Rather, these examples and embodiments are provided to fully convey the scope of this disclosure to those skilled in the art, as it is complete and all-encompassing.

[0024] Figure 1 shows a graph of the optical power spectrum (also referred to herein as the "spectral radiance spectrum") of blackbody radiation as a function of temperature, following Planck's law. As the temperature increases, the intensity of blackbody radiation increases, and the peak of its optical power spectrum shifts to shorter wavelengths. For example, as shown in Figure 1, a blackbody at 3,000°C has a luminance of approximately 15,000 (in arbitrary units) at 1,000 nm, but a luminance of approximately 5,000 at approximately 500 nm. As is well known, blackbody radiation is the thermal electromagnetic radiation emitted by a blackbody (an idealized opaque, non-reflective body). Blackbody radiation has a continuous wavelength spectrum distributed according to Planck's law, and its total luminance power or intensity depends mainly on the temperature of the blackbody, according to the Stefan-Boltzmann law. For example, a blackbody at room temperature (approximately 23°C) emits mainly in the infrared region of the electromagnetic spectrum. When the temperature of a blackbody rises to, for example, about 600°C, the magnitude of its emission increases, the emission spectrum expands into the human visible spectrum, and the blackbody appears red. As the temperature of the blackbody rises further, it emits orange, yellow, green, and violet light (and eventually beyond violet to ultraviolet light). Although a blackbody is an idealized concept, this concept still applies to ordinary objects, as they also emit blackbody radiation with a luminance proportional to the fourth power of the temperature and a spectrum described by Planck's law. If an object is not a perfect blackbody, the spectrum of radiation emitted from the object's surface also depends on the emissivity of that surface.

[0025] To detect blackbody radiation emitted from a surface at a certain temperature, the optical system that transmits the blackbody radiation to the detector must be able to transmit at least a portion of the wavelength range emitted at that temperature, and the detector must respond to at least a portion of the wavelength range of the blackbody radiation transmitted by the optical system. To measure blackbody radiation emitted from a surface at temperatures below approximately 25°C, for example, if the blackbody radiation is mainly in the mid-infrared portion of the electromagnetic spectrum, optical systems with high transmittance in that wavelength range, such as zinc sulfide (ZnS) or germanium (Ge) optical systems, or hollow waveguides are typically used to transmit the blackbody radiation, and thermocouples are typically used to detect the blackbody radiation. The transmittance of ZnS and Ge is much higher than that of silica or quartz at their mid-IR wavelengths, and thermocouples can be used to measure radiation at wavelengths longer than 2,600 nm. To measure blackbody radiation emitted from a surface at temperatures above approximately 25°C, for example, silica optics (or glass optics) and InGaAs photodiodes can also transmit and detect blackbody radiation, respectively, and may be used in place of or in addition to mid-IR optics and thermocouple detectors. To measure blackbody radiation emitted from a surface at temperatures above approximately 200°C, for example, silicon photodiodes can also detect blackbody radiation, and may be used in place of or in addition to thermocouple detectors or InGaAs detectors. To measure blackbody radiation emitted from a surface at temperatures above approximately 400°C, for example, plastic optical fibers can also transmit visible and near-infrared blackbody radiation, and may be used in place of or in addition to ZnS optics, Ge optics, hollow optical guides, silica fibers, or fiberglass. Embodiments described herein relate to instruments and methods used to measure the temperature of objects, surfaces, volumes, or regions by measuring the electromagnetic radiation emitted from these objects. The measured temperature of these objects, surfaces, volumes, or regions may be referred to herein as “object temperature.”In some embodiments, these objects, surfaces, volumes, or areas whose temperature can be measured relate to equipment used in semiconductor manufacturing, such as silicon wafers, electrostatic chucks, pedestals, edge rings, showerheads, valves, piping, and components of vacuum chambers; however, this approach can be used without limitation to other applications. The emitted radiation may include phosphorescent radiation (e.g., emitted by a phosphorescent sensing element excited by an excitation signal). The emitted radiation may also include blackbody radiation (e.g., emitted by an object or sensing element during phosphorescent radiation from a phosphorescent sensing element, after phosphorescent radiation from a phosphorescent sensing element has decayed, or when phosphorescent radiation from a phosphorescent sensing element is absent). In addition, blackbody radiation may be emitted by components of the temperature probe itself (e.g., housing, ferrule, sensing tip, etc.). Above temperatures above approximately 600°C, the intensity of blackbody radiation may increase as a proportion of the total radiation received by the temperature sensing system; however, as described herein, the temperature at which blackbody radiation becomes significant for measurement is a function of several parameters of the system.

[0026] The following detailed description relates to various embodiments of novel temperature sensors, sensor systems, and measurement methods. In various embodiments, these improved sensor systems can improve accuracy over a wider temperature range by utilizing the characteristics of the emitted signal that changes as a result of photoexcitation, and by utilizing the characteristics of the emitted signal that does not change as a result of photoexcitation. In some embodiments, both signals may be used simultaneously, while in other embodiments, each signal may be used at different times.

[0027] In various embodiments, these improved sensors, sensor systems, and measurement methods can measure temperature more accurately and over a wider temperature range by detecting both an emission signal (emitted in response to a photoexcitation signal) and a blackbody signal (emitted independently of any photoexcitation signal), and then separating and analyzing these signals using various instruments and methods. In addition, these novel sensor systems can utilize many of the same optical and optoelectronic hardware (e.g., light sources, detectors, optical components (fibers, filters, gratings, lenses, mirrors, etc.)) to detect and process both types of signals. Furthermore, by utilizing two or more separate temperature-dependent signals, it may be possible to reduce the effects of optical path variations, such as attenuation through the optical path or changes in spectral variation over time, due to the characteristics of components including the optical path. Also, by utilizing two different signals, it may be possible to predetermine the effect of each signal on attenuation.

[0028] For example, at temperatures where the measured intensities of both the emission signal and the blackbody signal are relatively identical, the temperature calculated from the emission signal and the optical power of the blackbody signal may be used to calculate a parameter that can be saved and used to improve the accuracy of blackbody temperature calculations at other temperatures. This parameter may characterize the surface emissivity, the transmission spectrum of the optical path, or both. The surface emissivity has a linear relationship with the measured blackbody power and can affect the temperature measured from the blackbody signal. By characterizing the emissivity using the temperature calculated from the emission signal, variations in emissivity can be corrected, and this correction factor can be applied over a wider temperature range. Similarly, an increase in optical path length (or a change in the material used in the optical path) can change the blackbody radiant power transmitted along the optical path, potentially causing errors in the measured temperature.

[0029] The combined effect of emissivity and changes in optical path attenuation can be predicted by applying the temperature calculated from the emission signal and the power of the blackbody signal, and calculating a new coefficient or other parameter that can be used to compensate for these effects at the temperature calculated from the blackbody signal. The equation derived from the Stefan-Boltzmann law. P = AεσcT 4 This is an ideal equation for the relationship between the power and temperature of blackbody radiation. Here, P is the power of the entire spectrum of blackbody radiation, A is the surface area, ε is the surface emissivity, σ is the Stefan-Boltzmann constant, c is a constant factor related to the optical path geometry and attenuation and other factors of the sensor system, and T is the temperature. Since a photodiode detects only a portion of the entire spectrum of blackbody radiation, and this portion changes with the temperature of the blackbody, the relationship between power and temperature measured using a photodiode can be characterized in different ways by using, for example, a shifted temperature parameter, a polynomial, a lookup table, or a similar equation using a combination of the above. For example, the following equation approximates the relationship between power and blackbody temperature measured by a silicon photodiode. P = k(T-T0) 4 Here, k is a parameter that describes a combination of factors including emissivity, optical path geometry, and attenuation, and T0 is an additional parameter. At temperatures T low enough that the power from the blackbody signal P allows for accurate temperature measurements from both the emission signal and the blackbody signal, for example, between about 500°C and about 650°C in the exemplary embodiment, the parameter k can be calculated and stored. This parameter k can then be applied to calculate emissivity-corrected or attenuation-corrected blackbody temperatures in this temperature range and other temperatures, such as higher temperatures, for example, between about 650°C and about 900°C in the exemplary embodiment, according to the following formula. T = T0 + (P / k) 1 / 4 Further refinement of this parameter k is conceivable by determining its value at different temperatures. One or more values ​​of this parameter k may be calculated at different times, for example, during the manufacture of the temperature measurement system, or provided as a known parameter of a given configuration, or calculated while the temperature sensor is in use. Further refinement of the relationship between measured blackbody power and blackbody temperature and other factors, enabling the characterization of optical path and emissivity, is conceivable, including the use of polynomial approximations, lookup tables, or both.

[0030] This approach describes a method for calibrating a radiation temperature sensor, either automatically or manually, by characterizing the emissivity, optical path geometry, and optical path attenuation of the radiation temperature sensor using an independent temperature reference value, in this case, a temperature calculated from luminescence attenuation. This method overcomes the emissivity and optical path dependence typically present in conventional radiation temperature sensors. Similarly, in other embodiments, the characteristics of the photoresponse signal are parameterized using the characteristics of the photoexcitation-independent signal (or vice versa) to reduce the uncertainty of the resulting temperature measurement.

[0031] This disclosure uses various terms relating to optical emission signals and optical signals transmitted to and from various elements, components, systems, or subsystems. These signals are divided into six groups. First, optical emission that excites a certain atomic species or acts to excite the response of a sensing element (e.g., a thermographic phosphor) is referred to herein as “excitation” emission or signal. Second, optical emission that is reflected from, partially absorbed by, or transmitted by a sensing element (e.g., a bandgap sensing element) is referred to herein as “irradiation” emission or signal. Third, optical emission or signal emitted by a sensing element in response to excitation emission is referred to herein as “luminescence,” “phosphorescence,” or “photoexcitation response” emission or signal. Fourth, optical emission or signal that is not due to excitation or irradiation emission is referred to herein as “blackbody” or “photoexcitation-independent” emission or signal. Fifth, optical emission or signal reflected from a sensing element that has received “irradiation” emission is referred to as “reflected” emission or signal. Furthermore, sensors may be designed to transmit light instead of reflect it, and for such sensors, transmitted radiation or signals may be interpreted as a substitute for the term reflected radiation or signals. Lastly, light radiation or signals received by detectors of sensing systems or instruments described herein that include (or may include) more than one of the above-mentioned “irradiation,” “phosphorescence,” “photoexcitation response,” “blackbody,” “photoexcitation-independent,” or “reflected” radiation or signals are referred to as “composite” radiation or signals.

[0032] Figure 2 shows a partial cross-sectional view of an exemplary embodiment of a temperature sensing device 100 (also referred to herein as “optical fiber temperature probe 100”, “temperature probe 100” or “probe 100”) that operates to measure the surface 52 of an object 50 or other object to be measured. The measured object temperature is defined as the temperature or temperature reading (calculated temperature) of an object, surface, volume or area designed to be measured by the temperature probe and sensor system described herein. The temperature probe 100 may include a ferrule 102, a tip 110, a sensing element 118, a probe body 126, and a waveguide 128. The ferrule 102 may include at least one bore 104 sized to accept at least one tip 110. The tip 110 may include a tip body 112 in which at least one counterbore 114 may be formed internally. The counterbore 114 may be sized to accept at least one temperature sensing element 118 (also referred herein as “sensing element 118” or “element 118”). The tip 110 and the sensing element 118 are positioned to be thermally connected to the surface 52 or other object to be measured. In the illustrated embodiment, the sensing element 118 is provided as a thermographic phosphor configured to absorb at least a portion of the photoexcitation radiation 130 (also referred to herein as the “photoexcitation signal 130”) that originates from a light source (e.g., a light source 218 shown in Figure 5, 6, or 7), propagates through the optical path (e.g., an optical path 250 shown in Figure 5, 6, or 7) and enters the sensing element 118 via the waveguide 128. The wavelength or spectrum of the photoexcitation signal 130 may be selected based on the excitation spectrum of the phosphor used for the sensing element 118. In one embodiment, the photoexcitation signal 130 emitted by the light source 218 may have a wavelength of about 405 nm or a wavelength in the range of about 385 nm to about 410 nm. In other embodiments, the photoexcitation signal 130 emitted by the light source 218 may have a wavelength between approximately 370 nm and approximately 700 nm, depending on the selection of the phosphor. Those skilled in the art will understand that the photoexcitation signal 130 may have any wavelength or spectrum.

[0033] In the illustrated embodiment, the sensing element 118 absorbs at least a portion of the photoexcitation signal 130 and, after the photoexcitation signal 130 has disappeared, emits a phosphorescent light signal 120 (also referred to herein as the "photoexcitation response signal 120") which is at least partially dependent on the temperature of the sensing element 118 and thereby has an intensity decay rate related to the object temperature of the surface 52. In some embodiments, the sensing element 118 may reflect a portion of the photoexcitation response signal 120 as a reflected signal 125 which may have optical properties related to the object temperature. In various embodiments, the ferrule 102, the tip 112, and the inner surface of the sensing element 118 may emit blackbody radiation 124 which can be coupled into the waveguide 128 as a photoexcitation-independent response signal 124. The photoexcitation response signal 120, the reflected signal 125, and the photoexcitation-independent response 124 may form a composite signal 122 that propagates through the waveguide 128 and the optical path 250 to a sensor subsystem (a sensor subsystem 201 as shown in Figures 5-7). In various embodiments, the decay rate of the intensity of the photoexcitation response signal 120 and its associated time constant (measured in units of time, e.g., milliseconds) may be characteristics of the phosphorescent material of the sensing element 118 and its temperature. “Time constant” is defined herein as the time required for the emission of light from the sensing element 118 to decrease to 1 / e (about 36.8%) of the measured intensity immediately after the photoexcitation signal 130 has disappeared. In various embodiments, the range of the desired time constant value may be selected by the choice of phosphorescent material. In some embodiments, the time constant may be in the range of about 1 ms to about 5 ms, while in other embodiments, the time constant may be in the range of about 0.2 ms to about 12 ms. Those skilled in the art will understand that in other embodiments, light-emitting sensing materials with time constants ranging from less than nanoseconds to several seconds or more than tens of seconds may be used. In various embodiments, a composite signal 122, which includes at least a portion of at least one of the photoexcitation response signal 120, the reflection signal 125, and the photoexcitation-independent response signal 124, may be analyzed to evaluate one or more properties (e.g., a first property and a second property) used to determine the temperature of an object, such as intensity decay rate, time constant, initial intensity, average intensity, and wavelength.In various embodiments, for example, within a certain object temperature range, the intensity of the photo-excitation response signal 120 may be significantly greater than the intensity of the reflection signal 125 and / or the intensity of the photo-excitation-independent response signal 124, and the object temperature may be determined using only one or more characteristics of the photo-excitation response signal 120.

[0034] In various embodiments, the “attenuation sampling period” may be defined as the number of time constants required for the signal intensity to decrease to a functionally meaningless level. For example, in one embodiment, after five time constants, the intensity of the photoexcitation response signal 120 may be about 0.7% of its original intensity. In various embodiments, the photoexcitation response signal 120 may be considered to be completely attenuated. Those skilled in the art will understand that any time or any number of time constants may be selected to define a functionally attenuated or completely attenuated photoexcitation response signal 120. In some embodiments, the composite signal 122 may also be attenuated, at least in part, because a portion of the composite signal 122 may contain all or part of the photoexcitation response signal 120. For the purposes of this disclosure, “sampling” means obtaining a reading from a measuring device such as a detector at a specific point in time (e.g., by a controller, data acquisition device, or sensing subsystem). For example, in one embodiment, “sampling” the detector during a decay sampling period means recording data from the detector after the optical excitation signal 130 has disappeared, receiving an optical signal, such as an excitation response signal 120 or a composite signal 122, and then recording data from the detector at intervals while the optical excitation response signal 120 decays. Of course, the detector may be sampled at any time and for any reason, including when the optical excitation signal 130 is introduced. For example, the detector may be sampled when no optical signal is incident on it in order to perform a baseline measurement of the physical properties of the detector. The sampled data is transmitted to and stored in a processor or controller configured to process the sampled data and calculate an object temperature measurement result to be displayed on a display, or transmitted to another device. In one embodiment, the temperature probe 100 may have an operating temperature range of about -200°C to about 1,000°C. In other embodiments, the temperature probe 100 may have an operating temperature range of about -100°C to about 750°C. Those skilled in the art will understand that the operating temperature range may be any value.Furthermore, those skilled in the art will understand that the temperature range of a phosphorescent-only temperature sensor system is at least partially limited by the specific selection of materials constituting the phosphorescent material, temperature probe 100, or temperature measurement system, and the ability to distinguish the intensity of the photo-excitation response signal 120 from the intensity of the photo-excitation-independent signal 124 and the intensity of the reflected signal 125 at (one or more) emission wavelengths. In various embodiments, the emission radiation received by the detector after a decay sampling period (also referred to herein as the "post-decay signal") may still be measurable and may need to be taken into account (e.g., subtracted or compensated) when processing the sampled data and calculating the object temperature measurement result. Those skilled in the art will understand that, in addition to intensity, other characteristics may be used to distinguish between different signals, and one or more of these may be used alone or in combination with other characteristics. Examples of other characteristics include spectral characteristics, such as the intensity of the signal within a spectral band, the presence of the signal within a spectral band, and the proportion of different signals.

[0035] In various embodiments, the sensing element 118 may be, but is not limited to, manganese-doped phosphors Mg4FGeO6:Mn, europium-doped phosphors La2O2S:Eu, Y2O3:Eu, LuPO4:Eu, dysprosium-doped phosphors YVO4:Dy, Y2O3:Dy, Y3Al5O 12The thermographic phosphor material may be provided as one of a wide range of thermographic phosphor materials, including :Dy, LuPO4:Dy, YAG:Dy, chromium-doped phosphors GdAlO3:Cr, Al2O3:Cr, LaGaO3:Cr, YalO3:Cr, any stoichiometry of these, or any combination thereof. The phosphor material may be selected based on various properties such as its excitation spectrum, emission spectrum, luminescence decay rate as a function of temperature, emission intensity as a function of temperature, operating temperature range, or any combination thereof. In various embodiments, the sensing element 118 may have an emission spectrum in the range of about 575 nm to about 775 nm. In various embodiments, the sensing element 118 may have an emission spectrum in the range of about 640 nm to about 720 nm. Those skilled in the art will understand that the emission spectrum of the sensing element 118 may have different ranges.

[0036] In various embodiments, the components of the temperature probe 100 (e.g., the ferrule 102 or the tip 110) may have multiple inner surfaces (e.g., surfaces 106, 108, and 116) that can emit blackbody radiation at multiple wavelengths or wavelength bands depending on the temperature. In various embodiments, the sensing element 118 may emit blackbody radiation in addition to phosphorescent radiation. For illustrative purposes, Figure 2 shows only the portion of the blackbody radiation propagating in the general direction of the probe body 126 and waveguide 128, but in various embodiments, the blackbody radiation can propagate in any direction. The blackbody radiation from the sensing element 118, the surface of the ferrule 102, the surface of the tip 110, and other blackbody radiation-emitting surfaces together forms blackbody radiation 124. The intensity and wavelength spectrum of the blackbody radiation 124 emitted from the surfaces of the ferrule 102 and the tip 110 may be influenced by the emissivity of the surfaces, e.g., surfaces 106, 108, and 116. The emissivity of these surfaces depends on several factors, including, but not limited to, the surface material, the surface roughness of the material, and the surface treatment (e.g., coating, passivation, plating), or any combination thereof. Those skilled in the art will understand that any of the broad range of material and surface attributes affects their emissivity. In various embodiments, the materials of the components of the temperature probe 100 that emit blackbody radiation 124 (e.g., the ferrule 102 and tip 112) may be formed from materials having known emissivity so as to improve the calibration of a system used to measure object temperature based on blackbody radiation. In various embodiments, one or more materials emitting blackbody radiation may be identical, while in other embodiments, they may include different materials. In various embodiments, one or more materials emitting blackbody radiation may be configured to have the same or essentially identical emissivity so as to improve the calibration of temperature sensing that is at least partially based on blackbody radiation. In various embodiments, the effective emissivity value may be determined, for example, as a single value or as multiple values, as a function of temperature, in order to improve the calibration of temperature sensing that is at least partially based on blackbody radiation.

[0037] In various embodiments, the temperature sensing system may be configured to exclude or ignore all or part of the blackbody radiation from sides other than the sensing element 118, for example, by positioning and configuring the sensing element 118 and the waveguide 128. For example, in various embodiments, the sensing element 118 may be positioned relatively close to or directly adjacent to the waveguide 128 to limit the collection of blackbody radiation 124 by the waveguide 128, for example. In various embodiments, the distance between the sensing element 118 and one end of the waveguide 128 (or one end of the optical fiber or fiber bundle containing the waveguide 128) may be less than about 5 mm, less than about 3 mm, less than about 1 mm, or close to zero.

[0038] As described herein, the intensity of blackbody radiation is directly proportional to emissivity, which (theoretically) ranges from zero (0) to (1). In various embodiments, the material emitting blackbody radiation may be formed from a material having a relatively low emissivity value, coated with such a material, or configured to have a relatively low emissivity value. This can reduce the intensity or power level of blackbody radiation at a given temperature (for example, compared to an uncoated material). The following table shows examples of approximate emissivity values ​​for materials having a relatively low emissivity at a particular temperature (emissivity varies with temperature). In various embodiments, typical ceramic materials used in high-temperature probes, such as silicon carbide or aluminum nitride, may have emissivity values ​​ranging from about 0.8 to about 0.95. In various embodiments, coating these with a relatively low emissivity material can reduce the intensity of blackbody radiation by a relatively significant amount. For example, a material with an emissivity of approximately 0.8 coated with a material with an emissivity of approximately 0.26 (chromium) or a material with an emissivity of approximately 0.03 (gold) can reduce the intensity of blackbody radiation to approximately one-third or one-twenty-fifth, respectively. Those skilled in the art will understand that a wide range of material and coating combinations can result in a wide range of emissivity values. [Table 1]

[0039] In various embodiments, the coating may have more than one layer, and each layer may be formed from a different material. In various embodiments, the coating may have multiple alternating layers of, for example, metal and dielectric material to form a coating surface with a low emissivity value. In various embodiments, at least a portion of the inner surface of the components of the temperature probe 100 (e.g., the ferrule 102 and / or tip 110) may be formed from or coated with one or more materials having an emissivity value of less than about 0.7, less than about 0.6, less than about 0.3, or less than about 0.1. Alternatively, the inner surface of the components of the temperature probe 100 may be uncoated and have an emissivity value of less than about 0.7, less than about 0.6, less than about 0.3, or less than about 0.1.

[0040] The photo-excitation-independent signal 124 may include several characteristics, such as the intensity of the blackbody radiation, the wavelength or spectrum of the blackbody radiation, etc. Various characteristics of the photo-excitation-independent signal 124 can be used to provide information to the sensor system controller for calculating the object temperature. In various embodiments, the photo-excitation-independent signal 124 propagating through the waveguide 128 to the sensor subsystem 201 (e.g., as shown in Figures 5, 6, and 7) may be emitted independently of any photo-excitation response signal. In various embodiments, the intensity of the photo-excitation-independent signal 124 may depend particularly on the surface temperature and surface emissivity.

[0041] In various embodiments, at least a portion of at least one of the photo-excitation response signal 120, the photo-excitation-independent signal 124, and the reflected signal 125 may be coupled to the waveguide 128 to form a composite signal 122. In various embodiments, portions of the photo-excitation response signal 120, the photo-excitation-independent signal 124, and the reflected signal 125 that are not coupled to the waveguide 128 are reflected by the probe body 126 or the end face of the waveguide 128. In various embodiments, the amount of composite radiation incident on the end face of the waveguide 128 and not coupled to the waveguide 128 is due to various factors including the angle of incidence of the blackbody radiation and the properties of the waveguide (e.g., waveguide material, refractive index of coating applied to the end face, etc.). In various embodiments, depending on the material of the waveguide 128, a portion of the composite signal 122 may be absorbed before reaching the sensor system 200.

[0042] Figure 3 shows a partial cross-sectional view of an exemplary embodiment of a temperature sensing device 100 (also referred to herein as the “temperature probe 100” or “probe 100”) that operates to measure the object temperature of a surface 52 of an object 50. Similar to Figure 2, the temperature probe 100 may include a ferrule 102, a tip 110, a sensing element 118, a probe body 126, and a waveguide 128. The ferrule 102 may include at least one bore 104 sized to accommodate at least one tip 110. The tip 110 may include a tip body 112 in which at least one counterbore 114 may be formed internally. The counterbore 114 may be sized to accommodate at least one temperature sensing element 118. The tip 110 and the sensing element 118 are arranged to be thermally connected to the surface 52 or other object to be measured. In the illustrated embodiment, the sensing element 118 is provided as a bandgap sensor having a temperature-dependent bandgap measurable by the reflection of at least a portion of the light irradiation radiation 140 (also referred to herein as the “irradiation signal 140”) that originates from a light source (e.g., a light source 218 shown in Figures 5, 6, or 7) and propagates through an optical path (e.g., an optical path 250 shown in Figures 5, 6, or 7) and a waveguide 128. The wavelength or spectrum of the irradiation signal 140 is selected based on the reflection spectrum of the bandgap sensing material used in the sensing element 118. In various embodiments, the irradiation signal 140 may have a broad wavelength band spanning a portion of the visible spectrum from about 450 nm to about 700 nm. In some embodiments, the photoexcitation signal 140 may have a wavelength band between about 370 nm and about 900 nm, depending on the selection of the bandgap sensing element 118. Those skilled in the art will understand that the irradiation signal 140 may have any wavelength or spectrum. In various embodiments, the bandgap sensing element 118 may be coupled to the waveguide 128 and reflect the illumination signal 140 as a reflected signal 125 that propagates toward the sensor subsystem 201 shown in Figures 5, 6, and 7. The properties of the reflected signal 125 are related to the temperature of the bandgap sensing element 118, and thus to the temperatures of the tip 110 and the surface 52. Analysis of one or more properties of the reflected signal 125 may be used to determine the object temperature.

[0043] In various embodiments, the sensor system may be configured, for example, by positioning and configuring the sensing element 118 and the waveguide 128, to exclude or ignore all or part of the blackbody radiation or other radiation from surfaces other than the sensing element 118. For example, in various embodiments, the sensing element 118 may be positioned relatively close to or directly adjacent to the waveguide 128 to limit the collection of signals or radiation other than the reflected signal 125. In various embodiments, the distance between the sensing element 118 and the waveguide 128 may be less than about 5 mm, less than about 3 mm, less than about 1 mm, or substantially zero.

[0044] Figure 4 shows graphs of the optical power spectra (also referred to herein as “spectral power distributions”) of an exemplary phosphorescent sensor at different temperatures, and the optical power spectra (also referred to herein as “spectral power distributions”) of a blackbody at different temperatures. The dashed line shows the explanatory optical power spectrum of the exemplary phosphorescent sensor, and the solid line shows the explanatory optical power spectrum of blackbody radiation. One important point in this graph is that the optical power spectrum of blackbody radiation shifts to the shorter wavelength side above approximately 600°C or 700°C, becoming more dominant in the response spectrum of the silicon detector (approximately 400 nm to 1,050 nm). A second important point in this graph is that the amplitude of the optical power spectrum of the exemplary phosphorescent sensor can decrease significantly above a temperature of approximately 500°C. The intensity of phosphorescent radiation emitted by many thermographic phosphors decreases with temperature due to an effect known as “quenching.” Quenching contributes to the increased dominance of blackbody radiation as part of the total radiation received when the temperature of the phosphor (and the object temperature) rises. The amount of quenching generally depends on the specific selection of the phosphorescent material. In various embodiments, the photoexcitation response signal 120 emitted by the phosphorescent sensing element 118 has an optical power spectrum that can be characterized by at least one optical bandwidth having at least one short wavelength and at least one long wavelength, with all or substantially all of the photoexcitation response signal 120 contained between this short and long wavelength. For example, referring to Figure 4, the short wavelength of the optical bandwidth of the photoexcitation response signal 120 may be about 550 nm, the long wavelength of this optical bandwidth may be about 850 nm, and the optical bandwidth may be about 300 nm. In other embodiments, at least 75% of the power of the photoexcitation response signal 120 is within the optical bandwidth, or at least 85% or at least 95% of the power of the photoexcitation response signal 120 is within the optical bandwidth. Since the detector can detect radiation over a wider wavelength range than the optical power spectrum of the photoexcitation response signal 120, the intensity of the blackbody radiation may begin to contribute to the total detection signal (e.g., composite signal 122) even at temperatures where there is little or no spectral overlap between the phosphorescent radiation and the blackbody radiation.For example, since the example silicon detector can detect wavelengths up to approximately 1,050 nm, the total detector signal may include a portion of the blackbody radiation (i.e., the photo-excitation-independent signal 124) depending on the temperature of the object being measured.

[0045] Optical filters can be placed in the optical path to reduce the amount of blackbody radiation reaching the detector; however, considerable measurement errors can still exist, particularly if the peak of blackbody radiation is close to or overlaps with the peak of radiation emitted by the phosphor. At relatively low object temperatures, for example below about 400°C, there may be little interference between blackbody radiation and phosphorescence. However, as the object temperature rises, the power of phosphorescence is eventually overwhelmed by the power of blackbody radiation, preventing the use of phosphorescence characteristics alone to determine the object temperature. In various embodiments, at least a portion of the blackbody radiation emitted at wavelengths longer than the optical power spectrum or the long-wavelength edge of the optical bandwidth of the photoexcitation response signal 120 emitted by the phosphorescence sensing element 118 can be filtered using, for example, a dichroic mirror, a short-pass filter, or other means well known to those skilled in the art. In various embodiments, the short-pass filter may be configured to have a cutoff wavelength located within about 10% of the long wavelengths of the optical bandwidth of the photoexcitation response signal 120.

[0046] In various embodiments, a portion of the blackbody radiation emitted at wavelengths shorter than the short-wavelength edge of the spectral power distribution of the phosphorescent detection element 118 can be filtered using similar means. In various embodiments, the notch filter may consist of one or more filter elements to filter out radiation outside the optical power spectrum of the phosphorescent material.

[0047] Figure 5 shows a schematic diagram of an exemplary embodiment of a temperature sensor system 200, including a sensor subsystem 201, an optical path 250, and a temperature probe 100. The sensor subsystem 201 is configured to provide an optical excitation signal 130 or an irradiation signal 140 and to measure one or more physical properties or characteristics of a composite signal 122 (including one or more portions of an optical excitation response signal 120, an optical excitation-independent signal 124, and / or a reflected signal 125) received from the temperature probe 100. The sensor subsystem 201 is optically connected to the temperature probe 100 via an optical path 250, which is configured to allow the composite signal 122 (including one or more portions of an optical excitation response signal 120, an optical excitation-independent signal 124, and a reflected signal 125) to propagate to the sensor subsystem 201. In various embodiments, the waveguide 128 of the temperature probe 100 is considered to be part of the optical path 250. In the illustrated embodiment, the optical path 250 is provided as an optical fiber or optical fiber bundle having a first end and a second end opposite to the first end. Thus, the waveguide 128 may be provided as an optical fiber, optical fiber bundle, optical rod or other optical guide having a first end and a second end opposite to the first end. In other embodiments, the optical path 250 may include an optical array configured to allow signals 120, 124, 125, and 122 to propagate through free space or a combination of free space, optical fiber, waveguide, and various optical elements such as refractive or reflective optical elements. In yet another embodiment, the optical path 250 may also include any of a wide range of optical elements that act to allow the photoexcitation signal 130 and / or the irradiation signal 140 (not shown in Figure 5) to propagate to the temperature probe 100.

[0048] In various embodiments, the sensor subsystem 201 provides a photoexcitation signal 130 (or irradiation signal 140) to the temperature probe 100 and receives and measures the returning photoexcitation response signal 120 and photoexcitation-independent signal 124. In these embodiments, the reflected signal 125 may be present in the optical path 250 but may be filtered by an optical element 220 or other optical element such as a filter 210 (which may be provided as a dichroic mirror). In various embodiments, the photoexcitation response signal 120, the photoexcitation-independent signal 124, and the reflected signal 125 may overlap in space as they propagate through the waveguide 128 and optical path 250 as they return from the temperature probe 100, and these may be collectively referred to as a composite signal 122.

[0049] In various embodiments, the sensing element 118 is provided as a bandgap sensing material, and the sensor subsystem 201 provides an irradiation signal 140 to the temperature probe 100 and receives and measures the returning photo-excitation-independent signal 124 and reflected signal 125. In various embodiments, the photo-excitation-independent signal 124 and the reflected signal 125 may overlap in space as they propagate together in the waveguide 128 and optical path 250 as they propagate from the temperature probe 100, and as described elsewhere in this specification, they may comprehensively form a composite signal 122. In addition, the spectrum of the irradiation signal 140 may overlap with the spectrum of the reflected signal 125, and for this reason, the optical element 220 must be capable of transmitting and reflecting light of the same wavelength. For example, the optical element 220 may be a beam splitter that allows a portion of the reflected signal 125 to reach the detector 206.

[0050] In the illustrated embodiment, the sensor system 200 or sensor subsystem 201 includes an optional housing 202 having at least one light source 218, at least one detector 206, at least one first optical element 220, and an optional at least one optical element 214, the optional optical element 222 (shown as a lens) being located within the housing 202 so as to be optically connected to the optical path 250. In various embodiments, a power supply 226, a controller 228, and an optional display 230 are electrically connected to the light source 218 and the detector 206 by a communication link 224, although in some embodiments, the power supply 226, controller 228, and display 230 may be located within or on the housing 202. In various embodiments, the controller 228 and the optional display 230 may be wirelessly connected to the detector 206 and the light source 218. If necessary, although not shown in Figures 5 and 6, the controller 226 may be configured to provide wired or wireless signals to additional equipment. In various embodiments, the detector 206 and light source 218 may be mounted on the substrate 204 or in the housing 202, as necessary. In some embodiments, the controller 228 may include both control and processing functions as required for operation. For example, the controller 228 may be configured to drive the light source 218 to emit at least one photo-excitation signal 130 or at least one irradiation signal 140 to the temperature probe 100 at the wavelength, intensity, and duration required for a particular function of the sensor subsystem 201. The detector 206 is configured to receive at least one or more portions of the photo-excitation response signal 120, the photo-excitation-independent signal 124, the reflected signal 125, and the composite signal 122, and to provide the controller 228 with at least one signal representing the photo-excitation response signal 120, the photo-excitation-independent signal 124, the reflected signal 125, and the composite signal 122. In various embodiments, the controller 228 may be configured to collect measurement data by sampling the detector 206 and other detectors or devices (e.g., temperature measuring devices).Furthermore, the controller 228 may be configured to separate the signal representing the composite signal 122 into at least one signal representing the photoexcitation response signal 120 and at least one signal representing the photoexcitation-independent signal 124. For example, in one embodiment, the controller 228 samples the detector 206 that provides the controller 228 with the signal representing the composite signal 122. If the signal representing the composite signal 122 does not change over time, the controller 228 can separate that portion of the signal as the signal representing the photoexcitation-independent signal 124. If the signal representing the composite signal 122 has an intensity attenuation rate, the controller 228 can identify that portion of the composite signal 122 having an intensity attenuation rate as the photoexcitation response signal 120.

[0051] The controller 228 is configured to calculate the object temperature based on at least one of the signals representing the photoexcitation response signal 120 and the photoexcitation-independent signal 124. The signal representing the photoexcitation-independent signal 124 includes at least one first characteristic of the signal representing the photoexcitation-independent signal 124, and the signal representing the photoexcitation response signal 120 includes at least one second characteristic of the signal representing the photoexcitation response signal 120, the first characteristic being identical to or different from the second characteristic. The first or second characteristic may include intensity or amplitude, change in intensity or amplitude over a period of time, intensity decay rate, optical power spectrum, or one or more portions of the optical power spectrum of the photoexcitation response signal 120 or the photoexcitation-independent signal 124. The controller 228 can then calculate the object temperature based on at least one of the first characteristic of the signal representing the photoexcitation-independent signal 124 and the second toxicity of the signal representing the photoexcitation response signal 120. A first characteristic of the signal representing the photoexcitation-independent signal 124 may include the intensity of the blackbody radiation or the intensity of the blackbody radiation at at least one wavelength. A second characteristic of the signal representing the photoexcitation response signal 120 may include the intensity attenuation rate or the intensity of the photoexcitation response signal 120 at at least one wavelength.

[0052] In one embodiment, the controller 228 may determine at least one signal representing the photoexcitation-independent signal 124 at a first time point (e.g., before the photoexcitation signal 130 is introduced) and at least one signal representing the photoexcitation response signal 120 at a second time point (e.g., after the photoexcitation signal 130 is introduced, or after the photoexcitation signal 130 has disappeared and the photoexcitation response signal 120 has decayed). The controller 228 may then calculate the object temperature based on at least one of the signal representing the photoexcitation-independent signal 124 determined at the first time point and the signal representing the photoexcitation response signal 120 determined at the second time point. The signal representing the photoexcitation-independent signal 124 at the first time point includes at least one first characteristic of the signal representing the photoexcitation-independent signal 124 at the first time point. For example, in various embodiments, the first or second characteristic may include intensity or amplitude, change in intensity or amplitude over a period of time, intensity decay rate, optical power spectrum, or one or more portions of the optical power spectrum.

[0053] The signal representing the photoexcitation response signal 120 at a second time point includes at least one second characteristic of the signal representing the photoexcitation response signal 120 at a second time point. In some embodiments, the first characteristic may be identical to the second characteristic. In other embodiments, the first characteristic may be different from the second characteristic. For example, in various embodiments, the first or second characteristic may include intensity or amplitude, change in intensity or amplitude over a period of time, intensity decay rate, optical power spectrum, or one or more portions of the optical power spectrum. The controller 228 may be configured to calculate the object temperature based on at least one first characteristic of the signal representing the photoexcitation-independent signal 124 at a first time point and at least one second characteristic of the signal representing the photoexcitation response signal 120 at a second time point. In various embodiments, the first characteristic of the signal representing the photoexcitation-independent signal 124 at a first time point includes the intensity of blackbody radiation, the wavelength of blackbody radiation, or the intensity of blackbody radiation at a certain wavelength.

[0054] In various embodiments, a second characteristic of the signal representing the photoexcitation response signal 120 at a second time point includes an intensity attenuation rate of the photoexcitation response signal 120 at the intensity of at least one wavelength of the photoexcitation response signal 120.

[0055] In addition, the controller 228 may also be configured to perform necessary calibration or compensation of various devices (e.g., detectors 206 and 208, light source 218, etc.). In various embodiments, the controller 228 may be calibrated to process measurement data received from detectors and other measuring devices in the sensor subsystem 201 and to calculate compensation, correction, or other processing functions to calculate the final object temperature measurement result. In various embodiments, the controller 228 may be configured to transmit the measurement data or results to other devices (e.g., displays, processing equipment, etc.).

[0056] In the illustrated embodiment, the optical element 220 may be a dichroic filter or a dichroic mirror. In various embodiments, the light source 218 may be configured to emit an optical excitation signal 130 directed towards the optical path 250 by a dichroic mirror 220 and a lens 222. In various embodiments, the optical element 220 may be configured to reflect the optical excitation signal 130 and allow the optical excitation-independent signal 124 and the optical excitation response signal 120 to pass through and propagate. For example, in the illustrated embodiment, the optical element 220 may be a dichroic filter configured to reflect more than 95% of the excitation signal 130 from the light source 218 toward the optical path 250 and allow more than 95% of the optical excitation-independent signal 124 and the optical excitation response signal 120 to pass through and propagate toward a second mirror or optical element 214 configured to reflect the optical excitation-independent signal 124 and the optical excitation response signal 120 toward the detector 206. In various embodiments, the optical properties of the optical element 220 may be selected based on the luminescence properties of different phosphorescent materials used in the sensing element 118. Those skilled in the art will understand that the optical element 220 may be configured to reflect any portion of various proportions of the photoexcitation signal 130 from the light source 218 into the optical path 250, and to transmit any portion of various proportions of the photoexcitation-independent signal 124 and the photoexcitation response signal 120. In various embodiments, the positions of the light source 218 and the detector 206 may be swapped, for example, by using a hot mirror instead of a cold mirror, if an optical element 220 that transmits the excitation signal 130 and reflects the photoexcitation-independent signal 124 and the photoexcitation response signal 120 is selected. Those skilled in the art will understand that the light source 210, the detector 206, and various optical elements can be positioned relative to the housing 202 and the optical path 250 in a wide variety of ways.

[0057] In various embodiments, although not shown in Figure 5, the optical element 220 may be provided as an optical splitter (e.g., a bulk optical beam splitter, an optical fiber splitter, a branched optical fiber bundle, or an optical circulator) instead of a dichroic filter or dichroic mirror. Those skilled in the art will understand that a wide variety of optical configurations can be used to direct the photoexcitation signal 130 or the irradiation signal 140 towards the optical path 250 and to propagate the composite signal 122 (including a portion of at least one of the photoexcitation response signal 120, the photoexcitation-independent signal 124, and the reflected signal 125) towards the detector 206. In various embodiments, the wavelength of the photoexcitation signal 130 emitted from the light source 218 and the transmission and reflection bands of the optical element 220 and the filter 210 may be selected to match the excitation and emission spectra of the phosphorescent sensor element 118. In other embodiments, the wavelength of the photoexcitation signal 130 emitted by the light source 218 and the transmission and reflection bands of the optical element 220 and filter 210 can be selected to match the excitation and emission spectra of a wide variety of phosphorescent detection elements.

[0058] Although only a single detector 206 is shown in Figure 5, any number of different detectors or detector arrays may be used depending on the wavelengths of the signals 120, 124, and 125 to be measured. In various embodiments, the radiation reaching multiple detectors or different detectors may include the photo-excitation response signal 120, the photo-excitation-independent signal 124, or the reflected signal 125 propagating from the optical probe 100 as described above with respect to Figure 2 or Figure 3.

[0059] In embodiments where the sensing element 118 is provided as a bandgap sensing material, the reflected signal 125 may have a wavelength similar to, substantially identical to, or identical to, the irradiation signal 140 emitted by the light source 218, or an optical power spectrum that partially overlaps with the optical power spectrum of the irradiation signal 140. The optical element 220 may be a beam splitter capable of both transmitting and reflecting the irradiation signal 140 and the reflected signal 125. In various embodiments, the detector 206 may be configured to receive the reflected signal 125 returning to the light source 218, and may be located inside or adjacent to the package or housing of the light source 218. In various embodiments where the optical element 220 is a beam splitter, a portion of the reflected signal 125 may be transmitted through the optical element 220 and received by the detector 206, while the other portion of the reflected signal 125 may be reflected by the optical element 220 and received by a detector inside or adjacent to the package of the light source 218. In various embodiments, the light source 218 may be configured to function as a detector, for example, when it is functionally unable to emit light or radiation.

[0060] (Not shown in Figure 5) In various embodiments, at least one temperature sensor (such as a thermocouple, thermistor, or second photodiode) may be configured to be thermally connected to the detector 206 and to provide information about the temperature of the detector 206 (also referred to herein as the “system temperature”), which can be used to identify and compensate for temperature-based influences of the detector or its amplification and / or processing circuits. In other embodiments, this temperature sensor may be mounted on or integrated with the detector 206. In addition, in various embodiments, at least one temperature sensor (such as a thermocouple, thermistor, or second photodiode) may be thermally connected to the controller 228 and further / or located in an optional housing 202, which can be used to identify and compensate for temperature-based influences of the controller 228 or its amplification and / or processing circuits, and to provide information about the temperature of the controller 228 and / or the temperature within the optional housing 202.

[0061] In various embodiments, at least one filter 210 may be positioned, for example between the detector 206 and the sensing element 118, so as to be optically connected to the detector 206, in order to prevent stray light (or light with wavelengths not intended to be detected) from reaching the detector 206. In various embodiments, the filter 210 may be a long-pass filter configured to transmit approximately 95% or more of the light emitted by the phosphorescent sensing element (for example, from about 575 nm to about 800 nm for the phosphorescent material shown in Figure 4) to the detector 206. The filter 210 may be provided as a combination of a short-pass filter, a band-pass filter, a notch filter, or a neutral filter. Those skilled in the art will understand that a wide range of filters with a wide range of performance specifications may be used. In some cases, no filter may be used.

[0062] In various embodiments, the detector 206 (detector 208 shown in Figure 6) may be provided as one of a wide range of detectors or instruments selected for their spectral response or wavelength reactivity, such as a photodiode, CCD or CMOS sensor, thermocouple, or bolometer. For example, in various embodiments, the detector 206 may be a silicon (Si) detector having a wavelength response range (also referred to herein as “reaction spectrum”) of, for example, about 400 nm to about 1,050 nm. In various embodiments, detectors 206,208 may be selected from a wide range of detectors, including, but not limited to, germanium (Ge), indium gallium arsenide (InGaAs), gallium arsenide (GaAs), lead(II) sulfide (PbS), cadmium mercury telluride (HgCdTe), gallium nitride (GaN), zinc cadmium telluride (CdZnTe), gallium phosphide (GaP), and cadmium mercury telluride (HgCdTe). Similar detectors may be used. In various embodiments, detectors 206,208 may be provided as a plurality of detectors, a multi-junction detector, or a detector array selected from the above list. In various embodiments, detectors 206,208 may be stacked in a “sandwich” configuration or may include a plurality of detector layers formed on top of each. In various embodiments, multiple detectors having different or partially overlapping response spectra may be arranged in a "bounce" configuration, where an optical signal is incident on a first detector (e.g., a silicon detector with a response spectrum from about 400 nm to about 1,050 nm), and the portion of the optical signal not absorbed by the first detector is reflected by a second detector (e.g., a germanium detector with a response spectrum from about 900 nm to about 1,600 nm). In this configuration, the combined wavelength response curve may not contain large gaps in the response across the combined response spectra of the two detectors. The remaining signal not absorbed by either detector may be directed to a beam dump. In various embodiments, the detectors may also be provided as thermocouples for detecting wavelengths in the near-infrared, mid-infrared, and far-infrared spectra.In various embodiments, the detector may be replaced by various optical analytical instruments such as spectrometers, spectrophotographers, and monochromators (e.g., Czerny-Turner monochromators). Those skilled in the art will understand that any of the wide range of detectors or instruments may be used to measure the physical properties of the composite signal 122 or other signals received from the temperature probe 100 or the optical path 250.

[0063] In various embodiments, the sensing element 118 may include one or more bandgap-type sensors or sensing materials having a temperature-dependent bandgap (i.e., an energy gap between the highest valence band level and the lowest conduction band level). The temperature-dependent bandgap can be measured by measuring the spectrum of light reflected from the bandgap-type sensing material when irradiated with an irradiation signal 140 (i.e., the “reflection spectrum”). The reflection spectrum may be characterized by a cutoff wavelength (e.g., measured in nanometer units), at which the intensity of the reflected light increases from a low measurement intensity to a high measurement intensity. Bandgap-type sensing materials include, but are not limited to, elemental semiconductor materials such as silicon (Si) or germanium (Ge), or compound semiconductor materials such as gallium arsenide (GaAs), indium phosphide (InP), silicon carbide (SiC), aluminum nitride (AlN), zinc sulfide (ZnS), zinc selenide (ZnSe), and cadmium telluride (CdTe), as well as a wide range of other compound semiconductor material alloys known to those skilled in the art.

[0064] In various embodiments, if the sensing element 118 is provided as a bandgap sensing material (e.g., GaAs) positioned to be thermally connected to the object being measured, the light source 218 may be configured to emit a broadband irradiation signal 140 incident on the sensing element 118 (e.g., from a white light source or another broadband light source (such as a white light-emitting LED, laser, or halogen light bulb)), and the optical element 220 may be configured to reflect and transmit white light (e.g., a beam splitter). In various embodiments, the bandgap sensing element 118 may be configured to reflect the irradiation signal 140 as at least one reflected signal 125 having a reflected spectrum. This reflected spectrum depends on the bandgap of the bandgap sensing material 118 at a given temperature. Thus, in this embodiment, the temperature probe 100 emits a composite signal 122 including at least a portion of the photoexcitation-independent signal 124 and at least a portion of the reflected signal 125. The sensor system 200 includes at least one optical path 250 configured to allow the irradiation signal 140 to propagate to the sensing element 118 and at least a portion (or all) of the composite signal 122 to propagate to the detector 206. The detector 206 is configured to provide the controller 228 with at least one signal representing the composite signal 122, and the controller 228 is configured to separate the signal representing the composite signal 122 into at least one characteristic of the photo-excitation-independent signal 124 and at least one characteristic of the reflected signal 125. The controller 228 is configured to calculate the object temperature based on at least one of the signal representing the photo-excitation-independent signal 124 and the signal representing the reflected signal 125.

[0065] In one embodiment, the composite signal 122 may be measured using a spectrometer or other spectroscopic measuring sensor instead of detector 206. In another embodiment, the composite signal 122 may be received by a detector, for example, at least one of detectors 206 and 208 (as described with respect to Figure 6). Detectors 206 and 208 are configured to generate signals representing at least a portion of the light intensity or wavelength of the composite signal 122. In various embodiments, a photoexcitation-independent signal 124 (e.g., from the temperature probe 100 when there is no irradiation signal 140) may be subtracted from the composite signal 122 (e.g., when the irradiation signal 140 is introduced) to generate a reflected signal 125. In various embodiments, the cutoff wavelength of a bandgap signal may be measured for this reflected signal 125 (e.g., by a spectrometer). In various embodiments, the object temperature associated with the measured cutoff wavelength may be calculated (e.g., in a controller 228). In various embodiments, blackbody radiation emitted from the bandgap sensing element 118 or components of the temperature probe 100 can be measured using the signal returned from the bandgap sensing element 118 when there is no irradiation signal 140. Based on this, the object temperature associated with the blackbody radiation can be calculated. In one embodiment, the blackbody radiation in the wavelength range of the spectrometer can be summed and used to estimate or determine the object temperature. In other embodiments, the optical power spectrum of the measured blackbody radiation is compared to the spectral radiance spectrum according to Planck's law, and the object temperature that most likely produced this spectral radiance spectrum can be estimated or determined, for example, through the least-squares approximation of the spectral radiance spectrum to a function representing Planck's law. In other embodiments, other semiconductor materials having a temperature-dependent bandgap may be used. Those skilled in the art will understand that different bandgap sensing materials can be selected based on a desired object temperature range, for example, based on the temperature sensitivity of the bandgap, the thermal stability of the bandgap sensing material, and other factors known to those skilled in the art.

[0066] Figure 6 shows a diagram of another embodiment of the sensor system 200, similar to that described with reference to Figure 5, but including two “measurement channels”. In this embodiment, the sensor subsystem 201, the optical path 250, and the temperature probe 100 are provided as described above with reference to Figure 5, except that an optional housing 202 may include a second optical element 216 positioned and configured to reflect at least a portion of the composite signal 122 to a second detector 208 optionally installed in the housing 202 or on the substrate 204. The sensor subsystem 201 is optically connected to the temperature probe 100 and is configured to direct the photoexcitation signal 130 or irradiation signal 140 to the temperature probe 100 via the optical path 250. The optical path 250 is configured to allow the composite signal 122 (including one or more portions of the photoexcitation response signal 120, the photoexcitation-independent signal 124, and the reflected signal 125) to propagate to the sensor subsystem 201. The sensor subsystem 201 is configured to measure one or more physical properties or characteristics of the composite signal 122 propagated from the temperature probe 100 (including the physical properties of one or more portions of the photo-excitation response signal 120, the photo-excitation-independent signal 124, and / or the reflected signal 125).

[0067] In various embodiments, the addition of an optical element 216, a detector 208, and a filter 212 adds a second “channel” to the sensor subsystem 201, increasing flexibility in configuring the sensor subsystem 201 for a wider range of measurement arrangements. Those skilled in the art will understand that the sensor subsystem 201 may include additional channels depending on the requirements of the end-use application. In various embodiments, the two-channel configuration shown in Figure 6 may be changed to a single-channel configuration, for example, by removing the optical element 216 or by changing the orientation of the optical element 216 so that the composite signal 122 does not enter the optical element 216. The properties of the optical element 216 may be selected to allow any of the various wavelengths or wavelength bands to pass through and propagate, and to reflect any of the various wavelengths or wavelength bands to the detector 208. In various embodiments, at least one second filter 212 may be arranged to be optically connected to the composite signal 122 and the second detector 208, for example, to prevent stray light or other radiation from reaching the detector 208. In one embodiment, filter 212 may be provided as a long-pass filter configured to transmit at least 95% of the light in the spectral power distribution of phosphorescence to the detector 208. In various embodiments, filter 212 may be a long-pass filter configured to remove all or most of the photoexcitation response signal 120, so that the detector 208 measures only the photoexcitation-independent signal 124. In some cases, the filter may not be located in the optical path above the second detector 208. Those skilled in the art will understand that any of the broad range of filters may be used, and that the filters may be configured to transmit or remove less than 95% or more than 95% of the incident light in various spectral ranges.

[0068] In one embodiment, optical elements 222, 220, 216, and 214 are configured so that a first portion of the composite signal 122 can propagate to a detector 206, and a second portion of the composite signal 122 can propagate to a second detector 208. In various embodiments, at least a portion of the first portion of the composite signal 122 includes a photoexcitation response signal 120, and at least a portion of the second portion of the composite signal 122 includes a photoexcitation-independent signal 124. In various embodiments, detector 206 is configured to receive the photoexcitation response signal 120, and the second detector 208 is configured to receive the photoexcitation-independent signal 124. When sampled by the controller 228, detectors 206 and 208 provide the controller 228 with signals representing the received signals.

[0069] In other embodiments, at least a portion of the first part of the composite signal 122 includes the reflected signal 125, and at least a portion of the second part of the composite signal 122 includes the photoexcitation-independent signal 124. In various embodiments, detector 206 is configured to receive the reflected signal 125, and a second detector 208 is configured to receive the photoexcitation-independent signal 124, and each detector is configured to provide these signals to the controller 228. In other embodiments, detector 206 is configured to receive the photoexcitation-independent signal 124, and a second detector 208 is configured to receive the reflected signal 125. When sampled by the controller 228, detectors 206 and 208 provide the controller 228 with signals representing a portion of the received signals.

[0070] Although not shown, one or more temperature sensors (such as thermocouples, thermistors, or photodiodes) may be arranged to be thermally connected to each of the detectors 206 and 208 and configured to provide information about the temperature of detectors 206 and 208, which can be used to identify and compensate for temperature-based influences. In other embodiments, the temperature sensors may be mounted on or integrated with detectors 206 and 208. Although not shown, one or more temperature sensors (such as thermocouples, thermistors, or photodiodes) may be further / or arranged in an optional housing 202 to be thermally connected to the controller 228 and configured to provide information about the temperature of the controller 228 and / or the temperature within the optional housing 202, which can be used to identify and compensate for temperature-based influences of the controller or its amplification and / or processing circuits.

[0071] While the embodiments described above with respect to Figures 5 and 6 show only a single temperature probe 100, those skilled in the art will understand that in other embodiments, for example, a sensor subsystem 201 may be configured to receive a composite signal 122 from multiple temperature probes 100. In various embodiments, the signals from multiple temperature probes 100 can be distinguished in various ways, such as using optical switches or detector sampling timing. In various embodiments, the multiple temperature probes may communicate only with dedicated optical components and detectors on multiple channels, such as channels 240 and 242 described herein with respect to Figure 6.

[0072] With respect to Figures 5 and 6, the embodiments of the sensor subsystem 201 described above utilize mirrors and filters to select the wavelength or wavelength range reaching the detector. In various embodiments, various optical instruments may be used to measure the physical properties of the composite signal 122. In such embodiments, the need for higher measurement fidelity (for example, which may be required to control the process temperature of various semiconductor manufacturing processes) may require additional information (such as optical power and wavelength) about the composite signal 122. In various embodiments, the optical power spectrum of the radiation from the sensing element 118 (whether provided as a thermographic phosphor or bandgap sensing material or other sensor type) may have this additional information about one of the photo-excitation response signal 120, the photo-excitation-independent signal 124, and the reflected signal 125, which can be best measured with finer resolution. For example, the optical power spectrum of a phosphorescent sensing element may change with temperature, and higher measurement fidelity may be required to characterize this effect. In various embodiments, the reflected signal 125 may be analyzed as a function of wavelength to determine the change in the cutoff wavelength of a bandgap sensing element. Furthermore, the change in the cutoff wavelength of this bandgap type sensing element can be used to determine the temperature of an object.

[0073] Figure 7 shows a schematic diagram of an embodiment of a temperature sensor system 300 configured to measure one or more spectral properties of a composite signal 122 received from a temperature probe 100 via at least one optical path 250. In various embodiments, the temperature sensor system 300 may include a sensor subsystem 201 which may include a light source module 215, an optical analysis module 340, and a measurement module 360. In various embodiments, the optical analysis module 340 may operate to improve measurement fidelity in order to separate the signals 120, 124, 125, and 122 received from the temperature probe 100 into one or more wavelength components measured by the measurement module 360 ​​to determine the change in the cutoff wavelength of a bandgap sensor, or to separate the composite signal 122 into distinct wavelength components at least partially. For example, the blackbody radiation spectrum changes with temperature, as described with reference to Figure 4, and the blackbody radiation spectrum may be measured spectrally in detail to identify which portion of the composite signal 122 contains blackbody radiation. In various embodiments, a spectrometer, spectrophotographer, or monochromator may be used to measure all spectral properties with finer resolution or an additional spectral window than can be achieved using a single detector or multiple detectors.

[0074] The light source module 215 may include a light source 218, an optical element 220, and at least a portion of an optical path 250. In various embodiments, the light source 218 may be configured to operate to emit at least one photoexcitation signal 130 or at least one irradiation signal 140, and to propagate the photoexcitation signal 130 or irradiation signal 140 toward an optical element 220 which may be configured to direct the photoexcitation signal 130 or irradiation signal 140 toward an optical path 250. In various embodiments, the optical path 250 may be configured so that the photoexcitation signal 130 or irradiation signal 140 propagates to a temperature probe 100 and then to a sensing element 118 which is positioned to be thermally connected to the object being measured. The optical path 250 may also be configured so that at least a portion of the composite signal 122 propagates from the temperature sensing device 100 to the optical analysis module 340. In various embodiments, the light source 218 may be provided as an LED or a laser, and the optical element 220 may direct the photoexcitation signal 130 toward an optical path 250 for measurements using, for example, a thermographic phosphor. In various embodiments, the light source 218 may be provided as a broadband light source or a white light source. The optical element 220 may direct the irradiation signal 140 to the optical path 250, for example, for bandgap type measurement. When the sensing element 118 is provided as a bandgap type sensing material, the sensing element 118 may be configured to reflect the irradiation signal 140 as at least one reflected signal 125 (as described herein with reference to Figure 2) as part of a composite signal 122 which may include at least one photoexcitation-independent signal 124 emitted by the surface of the temperature probe 100. In various embodiments, the composite signal 122 may include at least a portion of the reflected signal 125 and at least a portion of at least one photoexcitation-independent signal 124. When the sensing element 118 is provided as a thermographic phosphor, the sensing element 118 may be configured to emit at least one photoexcitation response signal 120 as part of a composite signal 122 which may include at least one photoexcitation-independent signal 124 emitted by the surface of the temperature probe 100. In various embodiments, the composite signal 122 may include at least a portion of the photoexcitation response signal 120 and at least a portion of at least one photoexcitation-independent signal 124.The optical path 250 may be configured so that at least a portion of the composite signal 122 propagates from the temperature probe 100 to the optical analysis module 340.

[0075] In the illustrated embodiment, the optical analysis module 340 may be provided as a Czerny-Turner monochromator configured to receive at least a portion of the composite signal 122 and separate the composite signal 122 into distinct wavelength components. Optionally, the optical analysis module 340 may be provided as any of various monochromators, spectrophotographers, spectrometers, etc. In various embodiments, the optical analysis module 340 may include an optional housing 342 having at least one inlet port 344 and at least one outlet port 346. In various embodiments, at least one first concave mirror 348, at least one planar diffraction grating 350, and at least one second concave mirror 352 may be arranged within the housing 342. In various embodiments, the composite signal 122 propagating from the temperature probe 100 may propagate through the optical elements 220 to the inlet port 344 of the optical analysis module 340, as shown as individual rays 322. In various embodiments, a first concave mirror 348 can direct a ray 322 to a diffraction grating 350, which can then diffract the ray 322 into individual wavelength components 324. These individual wavelength components 324 can then be directed by a second concave mirror 352 through an exit port 346 to a measuring module 360.

[0076] In various embodiments, the measurement module 360 ​​may include a receiver 362 having a plurality of spatially arranged receiver ports 364. Each receiver port 364 may include at least one detector 366 that operates to measure the power and / or wavelength of each wavelength component 324. In various embodiments, a plurality of waveguides 368 may be arranged to be optically connected to an exit port 346. Each waveguide 368 may be configured so that each of the wavelength components 324 propagates through the waveguide 368 to the corresponding detector 366 of the receiver 362. Figure 7 shows four receiver ports 364, four detectors 366, and four waveguides 368, but those skilled in the art will understand that the measurement module 360 ​​may include any number of receiver ports, detectors, and waveguides. In the illustrated embodiment, the measurement module 360 ​​also includes a power supply 376, a controller 378, and an optional display 380, which are in contact with the receiver 362 via a communication link 374. If necessary, the receiver 362 may include at least one wireless transmitter 370 configured to emit at least one wireless signal 372 to the controller 378 or a separate controller, processor, and / or optional display (not shown). If necessary, although not shown in Figure 7, the controller 378 may be configured to provide wired or wireless signals to additional equipment. In various embodiments, the controller 378 may be provided as the controller 228 described above with respect to Figures 5 and 6. In various embodiments, the reflected light signal 125 may be analyzed as a function of wavelength to determine a change in the cutoff wavelength of a bandgap sensing element. This change in the cutoff wavelength of the bandgap sensing element may then be used to determine the object temperature.

[0077] The optical analysis module 340 receives a composite signal 122 from the temperature sensing device 100 and is configured to separate this composite signal 122 into a plurality of distinct wavelength components 324 that propagate to a plurality of detectors 366. Each of the plurality of detectors 366 corresponds to at least one of the plurality of distinct wavelength components 324. Each of the plurality of detectors 366 is configured to provide the controller 378 with at least one signal representing the corresponding wavelength component 324. When the sensing element 118 is provided as a thermographic phosphor, the controller 378 is configured to separate the signals representing the plurality of distinct wavelength components 324 into at least one signal representing the photoexcitation response signal 120 and at least one signal representing the photoexcitation-independent signal 124. In various embodiments, the characteristics of the photoexcitation response signal 120 include the intensity attenuation rate of the photoexcitation response signal 120 or the intensity of at least one wavelength of the photoexcitation response signal 120. In various embodiments, the characteristics of the photo-excitation-independent signal 124 include the intensity of the blackbody radiation or the intensity of the blackbody radiation at at least one wavelength. The controller 368 is configured to calculate at least one object temperature based on at least one of the characteristics of the photo-excitation response signal 120 and the characteristics of the photo-excitation-independent signal 124. In other embodiments, when the sensing element 118 is provided as a bandgap sensing element, the controller 378 is configured to separate the signals representing each of a plurality of distinct wavelength components 324 into at least one signal representing the reflected signal 125 and at least one signal representing the photo-excitation-independent signal 124. The controller 368 is configured to calculate at least one object temperature based on at least one of the characteristics of the reflected signal 125 and the characteristics of the photo-excitation-independent signal 124.

[0078] In various embodiments, the sensor systems 200 and 300 disperse and measure the intensity of the composite signal 122 over more than one wavelength band. As the temperature rises, the cutoff wavelength of the bandgap sensing element increases such that the intensity of the reflected signal 125 is relatively low at wavelengths below the cutoff wavelength and relatively high at wavelengths above the cutoff wavelength. The relative intensity of the light measured in various wavelength bands may relate to the cutoff wavelength of the bandgap sensing element 118, which is determined and used with formulas, lookup tables, or other means to determine the object temperature. In various embodiments, the wavelength bands may measure separate spectral components of the composite signal 122. In various embodiments, the wavelength band associated with detector 206 may partially overlap with the wavelength band associated with detector 208 or other detectors. For example, the overlapping wavelength bands may be formed using an optical element 220 (or 216) (e.g., a filter) having a progressive cutoff wavelength such that light from the composite signal 122 can be incident on both detectors 206 and 208 or other detectors. Overlapping wavelength bands increase the wavelength range over which the sensor system 200 or 300 can measure the cutoff wavelength of a bandgap sensing element with a limited number of detectors. In various embodiments, the measurement of the cutoff wavelength may be related to the object temperature using formulas, lookup tables, or other means to determine the object temperature. The photo-excitation-independent signal 124 may be measured independently of the reflected signal 125 when there is no irradiation signal 140. As the object temperature increases, the intensity of the photo-excitation-independent signal 124 increases, and this increase in intensity occurs particularly on the shorter wavelength side by Planck's law, as described elsewhere in this specification. The relative intensities of the signals measured in multiple wavelength bands may be related to the object temperature, which is determined and associated with the photo-excitation-independent signal 124 using formulas, lookup tables, or other means. For example, the spectrum of the photo-excitation-independent signal 124 may be compared to the spectrum at a temperature calculated using Planck's law. By measuring the relative intensity of a portion of the spectrum of the composite signal 122 at various temperatures, the object temperature can be determined from either or both of the reflected signal 125 and the photo-excitation-independent signal 124.

[0079] Figure 8 shows an illustrative timing diagram of an operational embodiment of the sensor system 200 or 300, showing the timing of the excitation of the phosphorescent sensor element 118 by the photoexcitation signal 130 and the period for sampling (one or more) detectors 206 / 208 / 366 (also referred to herein as “detectors”) to measure the subsequent composite signal 122. The horizontal axis is time t, and the vertical axis is the light intensity P of the composite signal 122 incident on the detector during various sampling periods. The relative signal levels shown in Figure 8 are not necessarily shown to scale. In the illustrated embodiment, at time t0, the composite signal 122 incident on the detector consists only of a photoexcitation-independent signal 124 with intensity P1, such as coupled blackbody radiation 124. During the “excitation period” from time t1 to time t2, the controller 228 / 378 (also referred to herein as the “controller”) instructs the light source 218 to emit a photoexcitation signal 130 to excite the phosphorescent sensing element 118. The phosphorescent sensing element 118 receives the photoexcitation signal 130, begins to emit phosphorescence, and emits a photoexcitation response signal 120. Thus, from t1 to t2, the composite signal 122 includes both the photoexcitation response signal 120 and the photoexcitation-independent signal 124, and increases up to an intensity P3 at the end of the excitation period at t2. The photoexcitation response signal 120 increases as the phosphorescent sensing element 118 becomes excited. The length of the excitation period is selected so that the sensing element 118 reaches a sufficient level of excitation. In various embodiments, sufficient excitation may mean that the emission level of the phosphorescent material is saturated, but this is not an limitation of the disclosure, and in other embodiments, the emission level of the phosphorescent material may not be fully saturated. In various embodiments, saturation depends on the type of phosphor, temperature, and excitation conditions, which are particularly selected from the parameters. The excitation period ends at time t2 (for example, when the photoexcitation signal 130 is gone), and the "decay sampling period" begins. The phosphorescent sensor element 118 emits a photoexcitation response signal 120 that decays at a rate dependent on its temperature. At time t3, the intensity of the photoexcitation response signal 120 has decayed to a value of approximately 1 / e times the difference between the maximum intensity P3 and the intensity P1 of the photoexcitation-independent signal 124, so that the period from t2 to t3 becomes a single time constant (as defined elsewhere in this specification).As a result, the total intensity incident on the detector (e.g., any of detectors 206, 208, or 366) decreases to intensity P2 at time t3. In the illustrated embodiment, the decay sampling period ends at time t4 when the photo-excitation response signal 120 decays to a level below functionally detectable or to a level low enough for operation, and the total intensity incident on detector 206 decreases to or close to P1. At time t4, since the photo-excitation response signal 120 has decayed below a functionally detectable or operationally detectable level, the composite signal 122 mainly consists of the photo-excitation-independent signal 124 (in this case, blackbody radiation only), and the "blackbody sampling period" begins, which continues until time t5. After time t5, the excitation period, decay sampling period, and blackbody sampling period may be repeated as needed. In various embodiments, these periods may be repeated in the same order and for the same length. In other embodiments, these periods may be repeated in the same order but for different lengths. In other embodiments, these periods may be repeated in a different order. Those skilled in the art will understand that these periods may occur in any order and for any length.

[0080] Figure 9 shows an illustrative timing diagram of an operating embodiment of the sensor system 200 or 300, illustrating the timing of the irradiation of the sensing element 118 by the irradiation signal 140 (for example, when the sensing element 118 is provided as a bandgap sensing material as described herein). The horizontal axis is time t, and the vertical axis is the light intensity P of the composite signal 122 incident on the detector (e.g., any of detectors 206, 208, or 366) during various sampling periods. The relative signal levels shown in Figure 9 are not necessarily shown to scale. At time t0, the composite signal 122 incident on the detector contains only the photoexcitation-independent signal 124 (e.g., blackbody radiation). During the "irradiation period" from time t1 to time t2, the light source 218 emits the irradiation signal 140 reflected from the bandgap sensing element 118 as a reflected signal 125 with intensities P2-P1. Therefore, the time from t1 to t2 is also the "reflection sampling period," and when the reflected signal 125 is incident on the detector, the detector is sampled. Thus, from t1 to t2, the composite signal 122 includes both the photo-excitation-independent signal 124 and the reflected signal 125. At time t2, both the irradiation period and the reflection sampling period end as the irradiation signal 140 disappears. At time t2, since there is no irradiation signal 140, the composite signal 122 mainly includes the photo-excitation-independent signal 124 (in this case, only blackbody radiation), and the "blackbody sampling period" begins, which continues until time t3. After time t3, the blackbody sampling period may continue, or the irradiation period, reflection sampling period, and blackbody sampling period may be repeated as needed. In various embodiments, these periods may be repeated in the same order and for the same length. In other embodiments, these periods may be repeated in the same order but for different lengths. In yet another embodiment, these periods may be repeated in a different order. Those skilled in the art will understand that these periods may be performed in any order and of any length.

[0081] During the various excitation / irradiation / sampling periods described above, when a detector (e.g., one of detectors 206, 208, or 366) is sampled by a controller (e.g., controller 228 or 378), the detector is configured to provide the controller with at least one signal representing the composite signal 122. If the sensing element 118 is provided as a thermographic phosphor, the controller is configured to separate the signal representing the composite signal 122 into at least one signal representing the photoexcitation response signal 120 and at least one signal representing the photoexcitation-independent signal 124. If the sensing element 118 is provided as a bandgap sensing material, the controller is configured to separate the signal representing the composite signal 122 into at least one signal representing the reflection signal 125 and at least one signal representing the photoexcitation-independent signal 124.

[0082] Embodiments of sensor systems 200 and 300 described herein with respect to Figures 2-3 and 5-9 can be used to perform various measurements using a method that leverages the ability to calculate object temperature based on a composite signal by separating the composite signal into individual signals. In one embodiment, the method includes detecting a first type of composite signal 122 (e.g., by sampling one or more detectors) and separating it into at least one signal representing a photoexcitation response signal 120 and one signal representing a photoexcitation-independent signal 124, wherein the signal representing the photoexcitation response signal 120 includes at least one characteristic of the photoexcitation response signal 120 (e.g., from a thermographic phosphor), and the signal representing the photoexcitation-independent signal 124 includes at least one characteristic of the photoexcitation-independent signal 124 (e.g., a blackbody radiation signal), and the method includes processing these characteristics to calculate an object temperature result. In various embodiments, the characteristic of the photoexcitation response signal 120 is the intensity decay rate, and the characteristic of the photoexcitation-independent signal 124 is the intensity of blackbody radiation. In other embodiments, the characteristic of the photoexcitation response signal 120 is the intensity at a certain wavelength, and the characteristic of the photoexcitation-independent signal 124 is the intensity at a certain wavelength of blackbody radiation. In various embodiments, the controller 228 or 378 (also referred to herein as the “controller”) may be configured to calculate at least one object temperature based on at least one characteristic of the photoexcitation response signal 120 and at least one characteristic of the photoexcitation-independent signal 124. Other characteristics of the signals representing the photoexcitation response signal 120 and the photoexcitation-independent signal 124 may include the return power or phase shift of the photoexcitation response signal 120 in or within a certain wavelength band, reflections during the photoexcitation period, rise time constants during excitation, and various signals (relative or whole) or parts thereof.

[0083] In other embodiments, the method may include detecting a second type of composite signal 122 (for example, by sampling one or more detectors) and providing a signal representing the composite signal 122 to a controller. The controller is configured to separate the signal representing the composite signal 122 into at least one signal representing the reflected signal 125 and at least one signal representing the photoexcitation-independent signal 124. In various embodiments, the controller may be configured to calculate at least one object temperature based on at least one characteristic of the photoexcitation-independent signal 124 and at least one characteristic of the reflected signal 125. In some embodiments, the signal representing the photoexcitation-independent signal 124 includes at least one first characteristic of the signal representing the photoexcitation-independent signal 124, and the signal representing the reflected signal 125 includes at least one second characteristic of the signal representing the reflected signal 125. In some embodiments, the first characteristic is different from the second characteristic. In other embodiments, the first characteristic is identical to the second characteristic. In various embodiments, at least one of the first or second characteristic includes wavelength, intensity or amplitude, optical power spectrum, or one or more portions of the optical power spectrum.

[0084] Figure 10 shows an illustrative process flowchart 400 of an embodiment of a measurement method that operates to measure the temperature of an object using at least one of a sensor system 200 or 300. In the illustrated embodiment, the process flowchart 400 has five steps, but those skilled in the art will understand that in other embodiments there may be fewer or more steps, and further / or the steps may be performed in a different order. The first step, the “excitation step” 402, is performed, in which the light source 218 emits an excitation signal 130 during the excitation period (for example, as described above with respect to Figure 8) so that the sensing element 118 reaches a sufficiently high excitation and emission level. When the excitation period ends, the light source 218 is turned off. The length of the excitation period depends on the particular temperature sensor system configuration, the temperature range of the object to be measured, the particular phosphor, etc. In various embodiments, the length of the excitation period can be in the range of about 1 ms to about 20 ms, but the length of the excitation period is not limiting to the present disclosure. Information regarding the excitation step 402 (e.g., signal intensity, duration, wavelength, etc.) may be sent to and stored in the controller. At least one composite signal 122 (including at least one photoexcitation response signal 120 and at least one photoexcitation-independent signal 124) propagates from the temperature probe 100 through the optical path 250 to at least one of the detectors 206 and 208, or to the optical analysis module 340.

[0085] Following the excitation step 402, a “attenuation sampling” step 404 may be performed. The composite signal 122 is measured by repeatedly sampling the detector during the attenuation sampling period (for example, as described above with respect to Figure 8). In the illustrated embodiment, the detector itself may not be able to distinguish which part of the composite signal 122 is the photoexcitation response signal 120 and which is the photoexcitation-independent signal 124 (and / or reflected signal 125). For this reason, during the attenuation sampling period, the detector detects the attenuation rate of the composite signal 122. In various embodiments, sampling may also include an optional amplification step performed on the sampled signal to increase its signal level. In various embodiments, sampling may be performed in the analog domain or using an analog-to-digital (ADC) converter to convert the attenuated signal to the digital domain. In various embodiments, the peak intensity of the composite signal 122 may range from about 0.1 nanowatts to about 10,000 nanowatts, but the signal power is not limited to this disclosure. Examples of sampling parameters, though not limited to these, include the sampling frequency (time elapsed between samples) and the number of samples. In various embodiments, the sampling frequency may be selected to achieve a sufficiently high resolution for calculating the time constant. In various embodiments, the sampling frequency may be selected to provide at least 3 samples, at least 10 samples, at least 50 samples, at least 100 samples, or at least 400 or more samples over a period of a certain time constant. Samples may be collected over a period up to a certain time constant, or over several time constants.Furthermore, samples may be collected over a fixed period typically between approximately 1 ms and approximately 100 ms, or over a variable period that can vary based on one or more characteristics or parameters measured or calculated during or after the attenuation sampling step 404 (e.g., intensity of the photoexcitation signal 130, rise time of the photoexcitation signal 130), or over other characteristics of the composite signal 122. The values ​​of these sampling parameters may be selected to suit a particular measurement application. In various embodiments, at least one signal representing the intensity attenuation rate of the composite signal 122 may be sent to and stored in the controller.

[0086] After completing the decay sampling step 404, the next step may be an optional “system temperature measurement” step 406. The system temperature of detectors 206, 208, or 366 (also referred to herein as “detectors”), the region near the detectors, and / or the region near the controller may be measured by sampling temperature sensors (as described herein) that are thermally connected to the detectors, while simultaneously sampling the detectors themselves (one or more). Parameter characteristics of the dark currents of the detectors (also referred to herein as “dark current parameters”) may be calculated, as may the signal characteristics of the controller temperature. In other embodiments, the system temperature measurement step 406 may include sampling a second (unexcited) photodetector thermally connected to the detectors, while simultaneously sampling the detectors. The system temperature of the detectors is determined by these detectors, which are at least partially used to determine the dark current. Since the dark current of the detectors affects their readings when sampled, the object temperature is determined at least partially by correcting for the dark current of the detectors.

[0087] In some cases, this system measurement step 404 may include considering a lookup table based on known characteristics of the detector, based on either product information, the detector's previous calibration, or the controller temperature. In various embodiments, the system temperature measurement step 406 may be performed at a detector temperature measurement sampling rate throughout process 400, providing information on the detector temperature at each step in the process and / or at various intervals within one or more steps in the process. In various embodiments, the system temperature measurement step may be performed outside of the decay sampling period.

[0088] After completing the system temperature measurement step 406, the next step may be a blackbody radiation measurement step 408 in which a photo-excitation-independent signal 124 can be measured by sampling the detector. In various embodiments, this sampling may also include an optional amplification step to increase the signal level. In various embodiments, sampling may be performed in the analog domain or using an analog-to-digital (ADC) converter to convert the attenuated signal to the digital domain. The data representing the photo-excitation-independent signal 124 measurement may be sent to and stored in the controller. The data representing the photo-excitation-independent signal 124 may then be subtracted from the data representing the composite signal 122.

[0089] In various embodiments, the above steps may be repeated for second, third, and subsequent measurements commanded by the repeating loop 412. In addition, any of steps 402 to 408 may be repeated using the same repeating loop 412. Those skilled in the art will understand that the order of steps 402 to 408 may be changed as needed.

[0090] After the measurements of the composite signal 122 are compiled, the controller may perform a signal processing step 410 to calculate, for example, an object temperature value. In various embodiments, the time constant of the photoexcitation response signal 120 may be calculated using decay rate data compiled from detector sampling in the decay sampling step 404 as described above. In various embodiments, the time constant may then be compared with known data of the time constant (for example, from a lookup table or other reference containing known properties of the thermographic phosphor used) against temperature (for example, a lookup table or other reference may be stored in the controller's memory). This comparison may be used to calculate the object temperature associated with the photoexcitation response signal 120 when the photoexcitation-independent signal 124 is subtracted from the measured values ​​of the composite signal 122.

[0091] In various embodiments, the dark current parameter calculated in the system measurement step 406 may be subtracted from the blackbody signal measurement in step 408 to generate a dark current-corrected blackbody signal. In various embodiments, the dark current-corrected blackbody signal may be compared with known data of the blackbody signal (e.g., from a lookup table, formula, or other reference, which may be stored in the controller's memory) for temperature (e.g., a lookup table, formula, or other reference may be stored in the controller's memory). In various embodiments, this comparison may be used to calculate the object temperature associated with the photoexcitation-independent signal 124. In various embodiments, the value of at least one of the signals representing the photoexcitation response signal 120 and the signal representing the photoexcitation-independent signal 124 is reduced by the dark current value of the first detector 206, the second detector 208, or the detector 366. In various embodiments, steps 402 to 410 may be repeated for second, third, and subsequent measurements by an iterative loop 412, such as one commanded by the controller. In various embodiments, any of steps 402 to 410 may be repeated using the same iterative loop 412. Those skilled in the art will understand that the order of steps 402 to 410 may be changed as needed or for advantage.

[0092] In various embodiments, the controller may evaluate or compare other parameters as needed, in addition to the object temperature determined using the photo-excitation-independent signal 124 and the object temperature determined using the photo-excitation response signal 120, and may be configured to report or transmit only one of the object temperature values ​​in order to extend the range of the temperature measurement system beyond the operating range available using only one type of response signal. In various embodiments, for example, the operating range may be extended beyond the operating range of the system using only a phosphorescent sensor or a bandgap sensor by using only an object temperature determined from the photo-excitation-independent signal 124 that is above a specific object temperature value, or when the object temperature determined from the photo-excitation response signal 120 or the reflected light signal 125 is, above, or below a specific object temperature value.

[0093] In various embodiments, for example, various spectral characteristics of the photo-excitation-dependent signal 120, the photo-excitation-independent signal 124, and the reflected light signal 125, determined using sensor system 200 or 300 or other sensor systems, may be used to determine the object temperature or to determine which signal to use to determine the object temperature.

[0094] The various embodiments described above relate to measuring and characterizing the photoexcitation-independent signal 124 after the photoexcitation response signal 120 has decayed (e.g., after a predicted decay period). In various embodiments, the photoexcitation response component and the photoexcitation-independent component of the composite signal 122 may be measured using other excitation forms such as a sine wave, triangular wave, or any other arbitrary waveform relating to the photoexcitation signal 130. In various embodiments, the sensor system 200 or 300 may measure the photoexcitation-independent signal 124 while the photoexcitation response signal 120 is still decaying. In various embodiments, the decay rates of various thermographic phosphors as a function of temperature may be well known. The controller may include a library of this decay rate data (e.g., in the form of a lookup table, formula, or other form in non-volatile memory) so that the controller can recognize the photoexcitation-independent signal 124 during the decay sampling step 404.

[0095] In various embodiments, the photoexcitation response may be measured using excitation signals having different time dependencies. One time dependency is a square wave, but those skilled in the art will understand that the excitation signal may have other time dependencies, such as a sinusoidal or triangular wave. In some embodiments, the sensor system 200 may measure a photoexcitation-independent signal 124 periodically or continuously. In other embodiments, a sinusoidal excitation signal may generate a sinusoidal photoexcitation response having the same or similar period as the excitation signal but with a phase delay. In these embodiments, the phase delays of various thermographic phosphors as a function of temperature may be well known. The controller may include a library of this phase delay data (e.g., in lookup tables, formulas, or other forms in non-volatile memory) which may enable the determination of the object temperature from the phase delay value.

[0096] In various embodiments, the sensor systems 200 and 300 may include a temperature transition range having minimum and maximum values. The controller 228 / 378 may be configured to determine the object temperature using the photo-excitation response signal 120 when the object temperature falls below the minimum value of the temperature transition range, and to determine the object temperature using the photo-excitation independent signal 124 when the object temperature exceeds the maximum value of the temperature transition range. For example, as the temperature rises, the intensity of the phosphorescent radiation emitted by the thermographic phosphor (including, for example, the photo-excitation response signal 120) may decrease with temperature, for example, due to the quenching effect (as described herein). The amount or presence of the intensity decrease depends on the phosphorescent material as well as the temperature range used. This decrease may contribute to an increasing dominance of blackbody radiation (e.g., the photo-excitation independent signal 124) as part of the total radiation (e.g., the composite signal 122) received as the object temperature rises. For example, in various embodiments, the decrease in phosphorescence intensity above a certain temperature may result in the object temperature being calculated using a photo-excitation-independent signal 124, which has lower uncertainty than the object temperature calculated using the emission response signal 120. In various embodiments, depending on the choice of phosphorescent material, this temperature may be in the range of about 600°C to about 700°C, or about 650°C. Since the intensity of blackbody radiation is known to decrease at lower predicted object temperatures (as described, for example, by Planck's law), the object temperature calculated using the emission response signal 120 may have lower uncertainty than the photo-excitation-independent signal 124. In various embodiments, a temperature range between about 500°C and 650°C may be the temperature transition range. Within the temperature transition range, the object temperature may be calculated using a combination of the photo-excitation response signal 120 and the photo-excitation-independent signal 124. Various methods exist to determine the ratio of the photo-excitation response signal 120 to the photo-excitation-independent signal 124 that can be used to calculate the object temperature. The object temperature determined using these ratios is sometimes called the "composite temperature".

[0097] In various embodiments, the controller 228 / 378 may be configured to determine the object temperature when the object temperature falls below the temperature transition range using the photo-excitation response signal 120 at a second time, and to determine the object temperature when the object temperature exceeds the temperature transition range using the photo-excitation-independent signal 124 at a first time. In various embodiments, the object temperature determined from the photo-excitation-independent signal 124 at a first time may be used to determine whether the object temperature is above or below the temperature transition range. The controller may be configured to determine the object temperature when the object temperature is below the minimum value of the temperature transition range using the photo-excitation response signal 120 at a second time, and to determine the object temperature when the object temperature is above the maximum value of the temperature transition range using the photo-excitation-independent signal 124 at a first time, and to use a combination of the photo-excitation response signal 120 at a first time and the photo-excitation-independent signal 124 at a second time when the object temperature is within the temperature transition range.

[0098] FIG. 11 shows a graph of an exemplary embodiment of a weight function over an exemplary temperature transition range. In this embodiment, the temperature transition range has a minimum value (e.g., 500° C.) where the composite temperature is equal to the object temperature determined from the photoexcitation response signal 120 and a maximum value (e.g., 650° C.) where the composite temperature is equal [to] the object temperature determined from the photoexcitation (non) dependency signal 124. Thus, in this embodiment, the temperature transition rangeis 150° C. (650° C. minus 500° C). In other embodiments, the minimum value, the maximum value, and (thus the temperature transition range) can have any value. In one embodiment, the object temperature determined by the photoexcitation response signal 120 is used to determine whether the object temperature is above or below the temperature transition range. In other embodiments, the object temperature determined from the photoexcitation non-dependency signal 124 is used to determine whether the object temperature is above or below the temperature transition range. When below the minimum value, the composite temperature can be equivalent to the object temperature determined from the photoexcitation response signal 120. When above the maximum value, the composite temperature can be equivalent to the object temperature determined from the photoexcitation non-dependency signal 124. Within the transition range, in one embodiment, the composite temperature can be calculated using the weight function shown in FIG. 11. For example, in one embodiment, at a predicted object temperature of about 550° C., about 80% of the object temperature needs to be determined from the photoexcitation response signal 120 and about 20% of the object temperature needs to be determined by the photoexcitation non-dependency signal 124. Thus, the controller is configured to determine the object temperature when the object temperature is lower than the minimum value of the temperature transition range using the photoexcitation response signal 120, determine the object temperature when the object temperature is higher than the maximum value of the temperature transition range using the photoexcitation non-dependency signal 124, and use a combination of the photoexcitation response signal 120 and the photoexcitation non-dependency signal 124 when the object temperature is within the temperature transition range.

[0099] In other embodiments, the composite temperature within the temperature transition range can be calculated based on a weighted average expressed as follows. T c = (T 120 *W 120 +T 124 *W 124 ) / (W120 +W 124 ) Here, T c is a combined temperature, T 120 The object temperature, W, is determined by the photoexcitation response signal 120. 120 T is the weight for the photoexcitation response signal 120. 124 The object temperature, W, is determined by the light excitation-independent signal 124. 124 is the weight for the photoexcitation-independent signal 124. In various embodiments, the weight for each temperature component may be a preset function dependent on the object temperature determined from the photoexcitation response signal 120. In other embodiments, the weight for the weighted average may be stored in a lookup table. In yet another embodiment, the weighted average may be a function of relative stability, relative power, or other properties calculated while using the photoexcitation response signal 120 and the photoexcitation-independent signal 124. In various embodiments, other forms of weighting may be applied to calculate the composite temperature.

[0100] The above description illustrates embodiments and examples of the present invention and should not be construed as a limitation of the invention. While a small number of specific embodiments and examples have been described with reference to the drawings, those skilled in the art will readily understand that many modifications to the disclosed embodiments and examples, and even other embodiments, are possible without substantially departing from the novel teachings and merits of the invention. Accordingly, all such modifications to the subject matter described herein are intended to fall within the scope of the invention as defined in the claims. For example, those skilled in the art will understand that it is possible to combine the subject matter of any sentence, paragraph, example, or embodiment with some or all of the subject matter of other sentences, paragraphs, examples, or embodiments, unless such combination is incompatible with each other. Accordingly, the scope of this application should be determined by the appended claims, and anything equivalent to the claims falls within the scope of the invention.

Claims

1. A temperature sensor system, At least one light source configured to emit at least one photoexcitation signal, A temperature sensing device comprising at least one sensing element thermally connected to at least one object to be measured, wherein the at least one sensing element is configured to emit at least one photoexcitation response signal, and the at least one temperature sensing device is configured to emit at least one first composite signal comprising at least a portion of the at least one photoexcitation response signal and at least one photoexcitation-independent signal, At least one first detector configured to receive at least a portion of the at least one first composite signal, The at least one optical path is configured such that the at least one photoexcitation signal can be propagated to the at least one sensing element, and at least a portion of the at least one first composite signal can be propagated from the at least one temperature sensing device to the at least one first detector, At least one controller and Equipped with, (i) The at least one first detector is configured to provide the at least one controller with at least one signal representing the at least one first composite signal, (ii) The at least one controller is configured to separate the at least one signal representing the at least one first composite signal into at least one signal representing the at least one photoexcitation response signal and at least one signal representing the at least one photoexcitation-independent signal. Temperature sensor system.

2. The temperature sensor system according to claim 1, wherein the at least one controller is configured to calculate the object temperature based on at least one of the at least one signal representing the at least one photoexcitation response signal and the at least one signal representing the at least one photoexcitation-independent signal.

3. (i) The at least one signal representing the at least one photoexcitation-independent signal includes at least one first characteristic of the at least one signal representing the at least one photoexcitation-independent signal, (ii) The at least one signal representing the at least one photoexcitation response signal includes at least one second characteristic of the at least one signal representing the at least one photoexcitation response signal, The temperature sensor system according to claim 1.

4. The temperature sensor system according to claim 3, wherein at least one of the at least one first characteristic or the at least one second characteristic includes at least one of intensity or amplitude, change in intensity or amplitude over a period of time, intensity attenuation rate, optical power spectrum, or one or more portions of the optical power spectrum.

5. The temperature sensor system according to claim 4, wherein the at least one controller is configured to calculate the object temperature based on at least one of the at least one first characteristic of the at least one signal representing the at least one photoexcitation-independent signal and the at least one second characteristic of the at least one signal representing the at least one photoexcitation response signal.

6. The temperature sensor system according to claim 5, wherein the at least one first characteristic of the at least one signal representing the at least one photoexcitation-independent signal includes the intensity of blackbody radiation.

7. The system further comprises a first temperature measuring device configured to measure the system temperature of at least one of the first detectors, (i) The system temperature of the at least one first detector is used at least in part to determine at least one value of the dark current of the at least one detector, (ii) The temperature of the object is at least partially determined by the at least one value of the dark current of the at least one detector, The temperature sensor system according to claim 2.

8. The temperature sensor system according to claim 2, further comprising a temperature transition range, wherein the at least one controller is configured to determine the temperature of the object when the object temperature is below the temperature transition range using the at least one photo-excitation response signal, and to determine the temperature of the object when the object temperature is above the temperature transition range using the at least one photo-excitation independent signal.

9. A temperature sensor system, At least one light source configured to emit at least one photoexcitation signal, A temperature sensing device comprising at least one sensing element thermally connected to at least one object to be measured, wherein the at least one sensing element is configured to emit at least one photoexcitation response signal, and the at least one temperature sensing device is configured to emit at least one first composite signal comprising at least a portion of the at least one photoexcitation response signal and at least one photoexcitation-independent signal, At least one first detector configured to receive at least a portion of the at least one first composite signal, The at least one optical path is configured such that the at least one photoexcitation signal can be propagated to the at least one sensing element, and at least a portion of the at least one first composite signal can be propagated from the at least one temperature sensing device to the at least one first detector, At least one controller and Equipped with, The aforementioned temperature sensor system is (i) Determine at least one signal that represents the at least one photoexcitation-independent signal at a first time point, (ii) Determine at least one signal representing the at least one photoexcitation response signal at a second time different from the first time, (iii) Calculate the object temperature based on at least one of the at least one signal representing the at least one photoexcitation-independent signal determined at the first time and the at least one signal representing the at least one photoexcitation response signal determined at the second time. It is configured in such a way. Temperature sensor system.

10. (i) The at least one signal representing the at least one photoexcitation-independent signal at the first time includes at least one first characteristic of the at least one signal representing the at least one photoexcitation-independent signal at the first time, (ii) The at least one signal representing the at least one photoexcitation response signal at the second time includes at least one second characteristic of the at least one signal representing the at least one photoexcitation response signal at the second time, The temperature sensor system according to claim 9.

11. The temperature sensor system according to claim 10, wherein the at least one first characteristic of the at least one signal representing the at least one photoexcitation-independent signal at the first time is the intensity of blackbody radiation.

12. The first temperature measuring device is further configured to measure the temperature of at least one of the detectors, (i) The temperature of the at least one detector is used at least partially to determine the dark current of the at least one detector, (ii) The object temperature is determined at least partially by correcting the dark current of the at least one detector. The temperature sensor system according to claim 9.

13. The temperature sensor system according to claim 1, wherein the at least one sensing element includes a thermographic phosphor.

14. The temperature sensor system according to claim 1, further comprising at least one second detector configured to receive at least a portion of the at least one first composite signal.

15. A temperature sensor system, At least one light source configured to emit at least one photoexcitation signal, A temperature sensing device comprising at least one sensing element thermally connected to at least one object to be measured, wherein the at least one sensing element is configured to emit at least one photoexcitation response signal, and the at least one temperature sensing device is configured to emit at least one first composite signal comprising at least a portion of the at least one photoexcitation response signal and at least one photoexcitation-independent signal, At least one optical analysis module configured to receive at least a portion of the at least one first composite signal, The at least one optical path is configured such that the at least one photoexcitation signal can be propagated to the at least one sensing element, and at least a portion of the at least one first composite signal can be propagated from the at least one temperature sensing device to the at least one optical analysis module, At least one controller and Equipped with, (i) The at least one optical analysis module is configured to receive the at least one composite signal from the at least one temperature sensing device and to separate the at least one composite signal into a plurality of distinct wavelength components that propagate to at least one measuring module including a plurality of detectors, each of the plurality of detectors being configured to correspond to at least one of the plurality of distinct wavelength components and to provide the at least one controller with at least one signal representing each of the plurality of distinct wavelength components. (ii) The at least one controller is configured to separate the at least one signal representing each of the plurality of distinct wavelength components into at least one signal representing the at least one photoexcitation response signal and at least one signal representing the at least one photoexcitation-independent signal. Temperature sensor system.

Images