System and method for regulating the temperature of an imaging detector sensor

Abstract

The present invention is entitled "System and method for regulating the temperature of an imaging detector sensor". The present invention provides a detector assembly (15) that can be positioned to receive X-rays from an X-ray source (14) within an imaging system (10). The detector assembly (15) includes a plurality of detector elements (20). The detector assembly (15) also includes a temperature regulation system (50), the temperature regulation system including a plurality of temperature regulation devices (51), wherein each temperature regulation device (51) of the plurality of temperature regulation devices (51) is associated with a corresponding detector element (20) of the plurality of detector elements (20), and each temperature regulation device (51) is configured to independently maintain a consistent temperature on a portion of the corresponding detector element (20).

Description

Background Art

[0001] The subject matter disclosed herein relates to imaging systems, and more particularly to regulating the temperature of a detector sensor.

[0002] In computed tomography (CT), X-ray radiation is passed across a subject of interest (such as a human patient) and a portion of the radiation strikes a detector that collects image data. In a digital X-ray system, a photodetector produces a signal representing the amount or intensity of radiation striking a discrete pixel area of ​​the detector surface. The signal can then be processed to generate an image that can be displayed for viewing. In the images produced by such systems, it is possible to identify and examine internal structures and organs inside the patient's body. In a CT system, as the gantry is shifted around the patient, a detector array (comprising a series of detector elements or sensors) produces similar signals through various positions, allowing a volume reconstruction to be obtained.

[0003] A CT imaging system may include a solid-state detector that includes an array of photodiodes that detect light pulses from an array of scintillation crystals. The photodiodes are typically mounted in close proximity to the readout electronics to maintain the signal integrity of the photodiodes. In operation, the readout electronics generate heat that may affect the operation of the photodiodes. Therefore, it is desirable to provide cooling for the CT detectors. However, conventional cooling systems are more expensive and complex, and provide cooling for the detector array as a whole rather than for individual detector elements, which results in a slower thermal response. Summary of the invention

[0004] Certain embodiments commensurate with the scope of the originally claimed subject matter are summarized below. These embodiments are not intended to limit the scope of the claimed subject matter, but rather, these embodiments are intended only to provide a brief overview of possible forms of the subject matter. In fact, the subject matter may include a variety of forms that may be similar to or different from the embodiments described below.

[0005] According to one embodiment, a detector assembly is provided that is positionable to receive X-rays from an X-ray source within an imaging system. The detector assembly includes a plurality of detector elements. The detector assembly also includes a temperature regulation system that includes a plurality of temperature regulation devices, wherein each of the plurality of temperature regulation devices is associated with a corresponding detector element of the plurality of detector elements, and each temperature regulation device is configured to independently maintain a consistent temperature on a portion of the corresponding detector element.

[0006] According to another embodiment, a computed tomography (CT) detector assembly is provided. The CT detector assembly includes a detector element. The detector element includes: a scintillator array configured to convert X-rays into lower energy photons; a photodiode array configured to convert the photons into analog electrical signals; an electronic device configured to receive the analog electrical signals and convert the analog electrical signals into digital signals; and a flexible circuit coupled to both the photodiode array and the electronic device and configured to provide the analog electrical signals to the electronic device. The detector element also includes: a thermal shunt coupled to the electronic device and configured to receive heat generated by the electronic device; a thermal isolation layer disposed between the photodiode array and the thermal shunt and configured to thermally isolate the electronic device and the thermal shunt from the photodiode array, and a portion of the flexible circuit disposed between the photodiode array and the thermal isolation layer. The CT detector assembly also includes a temperature regulator coupled to the detector element and configured to maintain a consistent temperature across the photodiode array.

[0007] According to another embodiment, a computer tomography (CT) imaging system is provided. The CT imaging system includes: a gantry having an opening for receiving an object to be scanned; an X-ray source attached to the gantry and configured to emit X-rays through the opening; and a detector assembly attached to the gantry and configured to receive the X-rays. The detector assembly includes a detector element, which includes: a scintillator array configured to convert the X-rays into lower energy photons; a photodiode array configured to convert the photons into analog electrical signals; an electronic device configured to receive the analog electrical signals and convert the analog electrical signals into digital signals; and a flexible circuit coupled to both the photodiode array and the electronic device and configured to provide the analog electrical signals to the electronic device. The detector element also includes a thermal shunt coupled to the electronics and configured to receive heat generated by the electronics, a thermal isolation layer disposed between the photodiode array and the thermal shunt and configured to thermally isolate the electronics and the thermal shunt from the photodiode array, and a portion of the flexible circuit disposed between the photodiode array and the thermal isolation layer. The detector assembly also includes a temperature regulator coupled to the detector element and configured to maintain a consistent temperature across the photodiode array. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] These and other features, aspects, and advantages of the subject matter of the present disclosure will be better understood when the following detailed description is read with reference to the accompanying drawings, in which like characters refer to like parts throughout, and in which:

[0009] Figure 1 is a combined pictorial view and block diagram of a computed tomography (CT) imaging system as discussed herein;

[0010] Figure 2 is a schematic diagram of a side view of a detector sensor assembly having a temperature regulation system according to one embodiment;

[0011] Figure 3 is a schematic diagram of a side view of a detector sensor assembly having a temperature regulation system (e.g., having a heat diffusion layer) according to one embodiment;

[0012] Figure 4 It is shown that according to one embodiment Figure 2 A schematic diagram of a photodiode array of a detector sensor assembly relative to a portion of a flexible circuit having a temperature regulating device (e.g., a heating element);

[0013] Figure 5 FIG. 1 is a diagram showing a device having a temperature adjustment device according to an embodiment Figure 4 a schematic diagram of the remaining portion of the flexible circuit;

[0014] Figure 6 According to an implementation scheme Figure 4 and Figure 5 A schematic diagram of a control structure of a temperature regulating device;

[0015] Figure 7 is a schematic diagram of a side of a detector sensor assembly having a temperature regulation system (e.g., having a positive temperature coefficient (PTC) heater disposed between a photodiode array and a flexible circuit) according to one embodiment;

[0016] Figure 8 is a schematic diagram of a side of a detector sensor assembly having a temperature regulation system (e.g., having a PTC heater disposed between a flexible circuit and a thermal isolation layer) according to one embodiment;

[0017] Fig. 9 is a schematic diagram of a side view of a detector sensor assembly having a temperature regulation system (e.g., having a PTC heater integrated within a flexible circuit) according to one embodiment; and

[0018] Fig.10 It is shown that according to one embodiment Figure 7 Schematic diagram of the detector sensor assembly's photodiode array relative to the PTC heater. DETAILED DESCRIPTION

[0019] One or more specific embodiments will be described below. In order to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be understood that in the development of any such actual implementation, as in any engineering or design project, many implementation-specific decisions must be made to achieve the developer's specific goals, such as complying with system-related and business-related constraints that may vary from implementation to implementation. In addition, it should be understood that such development efforts may be complex and time-consuming, but are still routine tasks for design, fabrication, and manufacturing for ordinary technicians who benefit from this disclosure.

[0020] When introducing elements of various embodiments of the present subject matter, the articles "a," "an," "the," and "said" are intended to indicate that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive, and mean that there may be additional elements in addition to the listed elements. Furthermore, any numerical examples in the following discussion are intended to be non-limiting, and thus the additional numerical values, ranges, and percentages are within the scope of the disclosed embodiments.

[0021] Various embodiments provide an imaging system (e.g., a computed tomography (CT) imaging system) that includes a temperature regulation system that provides temperature regulation for individual detector elements or sensors (e.g., via local control and feedback). In some embodiments, the temperature regulation system includes a separate temperature regulation device associated with each individual detector element that independently maintains a consistent temperature on the photodiode array of the detector element. Each detector element may include a thermal isolation layer and a heat shunt (e.g., a heat sink) that keeps heat generated by the electronics away from the photodiode array of the detector element. The temperature regulation device may include a plurality of heating elements (e.g., a resistor array) and associated thermistors integrated within a flexible circuit, wherein the heating element heats the photodiode array to a specified temperature, and the thermistor provides temperature feedback. In some embodiments, the temperature regulation device includes a semiconductor positive temperature coefficient (PTC) heater that self-regulates the PTC heater temperature to maintain the photodiode array at a specified temperature. The temperature regulation system can enable the entire detector to have a faster thermal response, which corresponds to a faster time for the entire CT system to be ready for acquisition. In addition, the temperature regulation system provides a lower cost thermal solution than a typical cooling system. Although the following techniques are described in the context of a CT imaging system, the temperature regulation system may be used with other imaging systems such as a positron emission tomography imaging system or an ultrasound imaging system.

[0022] Taking into account the foregoing and referring to Figure 1, a CT imaging system 10 is shown by way of example. The CT imaging system includes a gantry 12. The gantry 12 has an X-ray source 14 that projects a beam of X-rays 16 toward a detector assembly 15 on an opposite side of the gantry 12. The detector assembly 15 includes a collimator assembly 18, a plurality of detector modules 20 (e.g., detector elements or sensors), and a data acquisition system (DAS) 32. The plurality of detector modules 20 detect the projected X-rays that pass through a patient 22, and the DAS 32 converts the data into digital signals for subsequent processing. Each detector module 20 in a conventional system generates an analog electrical signal that represents the intensity of the incident X-ray beam and, therefore, the intensity of the beam that is attenuated when the incident X-ray beam passes through the patient 22. During scanning to acquire X-ray projection data, the gantry 12 and components mounted thereon rotate about a rotation center 24 to collect attenuation data from multiple viewing angles relative to the imaging volume.

[0023] The rotation of the gantry 12 and the operation of the x-ray source 14 are controlled by a control mechanism 26 of the CT system 10. The control mechanism 26 includes an x-ray controller 28, which provides power and timing signals to the x-ray source 14, and a gantry motor controller 30, which controls the rotation speed and position of the gantry 12. An image reconstructor 34 receives sampled and digitized x-ray data from the DAS 32 and performs high-speed reconstruction. The reconstructed image is applied as input to a computer 36, which stores the image in a mass storage device 38. The computer 36 also receives commands and scanning parameters from an operator via a console 40. An associated display 42 allows the operator to observe the reconstructed image and other data from the computer 36. The computer 36 uses the commands and parameters provided by the operator to provide control signals and information to the DAS 32, the x-ray controller 28, and the gantry motor controller 30. In addition, the computer 36 operates a table motor controller 44, which controls a motorized table 46 to position the patient 22 and the gantry 12. Specifically, the table 46 moves portions of the patient 22 through a gantry opening or aperture 48 .

[0024] Figure 2is a schematic diagram of a side of a detector sensor assembly 20 (e.g., a detector module or a detector element) having a temperature regulation system 50. The temperature regulation system 50 may include a plurality of temperature regulation devices 51, each of which is associated with a corresponding detector sensor assembly 20. Each temperature regulation device 51 can independently regulate or maintain a temperature on a portion (e.g., a photodiode array) of a corresponding detector sensor assembly 20. In certain embodiments, the temperature regulation device 51 is configured to receive feedback related to a corresponding temperature of a corresponding detector sensor assembly 20, and control or regulate the temperature of the corresponding detector sensor assembly 20 based on the feedback. In certain embodiments, the temperature regulation device 51 may include a heating element (e.g., a resistor array) disposed within a flexible circuit adjacent to the photodiode array. In certain embodiments, the temperature regulation device may include a positive temperature coefficient (PTC) heater disposed within or near the flexible circuit adjacent to the photodiode array.

[0025] The detector sensor assembly 20 includes a scintillator array 52, a photodiode array 54, and an electronic device 56 (e.g., one or more application-specific integrated circuit (ASIC) packages). As shown, the photodiode array 54 is disposed below the scintillator array 52. ​​The scintillator array 52 can be formed by one or more scintillator crystals that are configured to convert X-rays into lower energy photons (i.e., absorb X-rays and emit the absorbed energy in the form of light). The photodiode array 54 includes one or more photodiodes that receive photons and convert them into corresponding electrical signals (e.g., analog electrical signals) for reconstructing an image of the scanned object. The electronic device 56 is configured to receive the analog electrical signal and convert it into a digital signal. The electronic device 56 may include circuits for readout, amplification, and analog-to-digital (A / D) conversion (e.g., linear A / D conversion).

[0026] The detector sensor assembly 20 includes a flexible circuit 58 (e.g., a single flexible circuit) that is mechanically and electrically coupled to both the photodiode array 54 and the electronics 56. The flexible circuit 58 provides analog electrical signals to the electronics 56. The flexible circuit 58 is coupled to a digital printed circuit board (PCB) 60 via a digital connector 62. The digital PCB 60 may include control circuitry for acquiring image data from the detector sensor assembly 20, receiving feedback from the thermostat 51, and controlling or regulating the thermostat 51. The flexible circuit 58 provides digital signals from the electronics 56 to the digital PCB 60. In addition, the flexible circuit 58 provides signals to the thermostat 51 and from the thermostat to the digital PCB 60.

[0027] The detector sensor assembly 20 also includes a thermal shunt (e.g., an ASIC thermal shunt) or heat sink 64. The thermal shunt 64 is coupled to the electronic device 56. The thermal shunt 64 receives or absorbs heat generated by the electronic device 56. The thermal shunt 64 can be thermally coupled to components of the detector assembly 15 (e.g., rails, frames, etc.) to transfer heat from the electronic device 56 to these components. The thermal shunt 64 can be made of aluminum, copper, aluminum nitride, or any other thermally conductive metal. The detector sensor assembly 20 also includes a thermal isolation layer or block 66 to thermally isolate the electronic device 56 and the thermal shunt 64 from the photodiode array 54. The thermal isolation layer 66 can be made of glass reinforced epoxy laminate (e.g., FR-4), thermoplastic (e.g., polyoxymethylene), or any other electrically insulating material. The thermal isolation layer 66 is disposed between the thermal shunt 64 and the flexible circuit 58. Specifically, a first portion 68 of the flexible circuit 58 extends over the thermal isolation layer 66 between the thermal shunt 64 and the photodiode array 54, while a second portion 70 of the flexible circuit 58 extends along the thermal isolation layer 66 and the side 72 of the thermal shunt 64 to the digital connector 62. In some embodiments (see Figure 3 ), a heat diffusion layer 74 may be disposed between portion 68 of the flexible circuit 58 and the thermal isolation layer 66. The heat diffusion layer 74 may be made of graphite or graphene.

[0028] Figure 4 It is shown Figure 2Schematic diagram (e.g., top view) of a photodiode array 54 of a detector sensor assembly 20 relative to a portion 68 of a flexible circuit 58 having a temperature adjustment device 51 (e.g., a heating element 76). As shown, the photodiode array 54 includes a plurality of photodiodes 78 spaced apart from each other. The temperature adjustment device 51 includes a plurality of heating elements 76, which are integrated in and extend on a portion 68 of the flexible circuit 58 between the photodiodes 78 of the photodiode array 54. In response to a signal from a control circuit (e.g., on a digital PCB 60), the heating element 76 can be heated to maintain a consistent temperature (or temperature range) on the photodiode array 54. As shown, the heating element 76 extends in the x-direction (e.g., relative to a plane parallel to the portion 68 of the flexible circuit 58). In some embodiments, the heating element 76 may extend in the y-direction, for example, orthogonal to the x-direction (in a plane parallel to the portion 68 of the flexible circuit 58) or in both the x-direction and the y-direction. Each heating element 76 includes a plurality of resistors 80 (e.g., a resistor array). As shown, three heating elements 76 (heating elements 82, 84, 86) are depicted within the portion 68 of the flexible circuit 58. The number of heating elements 76 can vary (e.g., 2, 3, 4, 5 or more heating elements 76). As shown, the heating elements 82, 84 are disposed near the edges 88, 90 of the portion 68 of the flexible circuit 58, respectively, while the heating element 86 is located in the center as shown by arrow 92. In certain embodiments, each heating element 76 can be used to maintain the temperature at the same temperature set point or range. In other embodiments, depending on the location of the heating elements 76, different heating elements 76 can be utilized to maintain the temperature at different set points or ranges. For example, the heating elements 82, 86 near the edges 88, 90 can be the portion of the control loop that maintains the temperature at a first temperature set point or range, while the heating element 84 can be the portion of the control loop that maintains the temperature at a second temperature set point or range that is different from the first temperature set point or range.

[0029] The time it takes for the detector to reach thermal stability from a cold start or system restart is considerable and may result in delays in patient scanning. However, because the heating element 76 is disposed near the photodiode array 54, the temperature regulator 51 provides significantly faster temperature control than typical cooling techniques. In addition, due to the temperature regulator 51, the detector sensor no longer requires external heating and heating elements. Self-heating of the detector sensor (via the temperature regulator 51) may be sufficient for accurate temperature regulation.

[0030] Figure 5 It is shown Figure 4Schematic diagram of the remaining portion 70 of the flexible circuit 58 with the temperature regulating device 51. The portion 68 of the flexible circuit 58 has the heating element 76 of the temperature regulating device 51, such as Figure 4 As shown. Figure 5 As shown, the portion 70 of the flexible circuit 58 is coupled to the electronic device 56 (e.g., multiple ASIC packages) and the digital connector 62, as described above. In addition, multiple temperature sensors or thermistors 94 are embedded in the portion 70 of the flexible circuit 58. In some embodiments, the thermistor 94 can be a negative temperature coefficient thermistor. As shown, three thermistors 94 (thermistors 96 (NTC1), 98 (NTC2), 100 (NTC3)) are depicted in the portion 70 of the flexible circuit 58. The number of thermistors 94 can vary based on the number of heating elements 76 (e.g., 2, 3, 4, 5 or more thermistors). Thermistors 96, 98, 100 are coupled to heating elements 82, 84, 86, respectively. Thermistors 94 provide temperature feedback (via changes in resistance) from the areas where they are located. Based on the temperature feedback from the thermistors 94, the control circuit associated with the digital PCB 60 can adjust the heating of the heating element 76. For example, the control circuitry may adjust the respective heating of each heating element 76 based on respective feedback from respective thermistors 94 associated with the heating elements 76. The architecture of the thermal conditioning device 51 reduces the temperature gradient across the detector sensor.

[0031] Figure 6 yes Figure 4 and Figure 5 Schematic diagram of the control structure of the temperature regulating device 51 in FIG. The flexible circuit 58 includes a heating element 76 and a thermistor 94, such as Figure 4 and Figure 5As shown. The digital PCB 60 includes a control circuit 102. In certain embodiments, the control circuit 102 may include a field programmable gate array. The control circuit 102 includes a processing circuit that executes instructions stored in a memory (e.g., on a non-transitory computer-readable medium). The control circuit 102 is used to collect image data from the detector sensor assembly 20, receive feedback from the temperature regulating device 51, and control or adjust the temperature regulating device 51. As shown, the control circuit 102 includes a plurality of proportional integral differential (PID) controllers 104 (e.g., PID controller 106 (PID1), PID controller 108 (PID2), PID controller 110 (PID3)). The PID controllers 106, 108, 110 form a closed PID control loop with the corresponding heating elements 82, 84, 86 and the corresponding thermistors 96, 98, 100. The PID controller 104 receives a temperature set point 112 as an input (e.g., from a memory) and provides an output control signal to the corresponding heating element 76 to heat the heating element 76 to achieve the temperature set point 112. In some embodiments, a desired temperature range can be provided as an input to the PID controller 104, and the PID controller 104 can utilize a dead band. The PID controller 104 receives an input (e.g., temperature feedback) from the corresponding thermistor 94 to enable the PID controller to regulate the heating of the heating element 76, thereby regulating the temperature on the photodiode array 54. In some embodiments, the temperature set point 112 can be the same for each PID control loop. In other embodiments, the temperature set point 112 can be different for the PID control loops. For example, the PID control loop of the heating element 76 (e.g., heating elements 82, 86) adjacent to the edge of the flexible circuit 58 can have a different temperature set point 112 than the PID control loop of the heating element 76 (e.g., heating element 84) located in the center. In certain embodiments, the control circuit 102 may have a single PID controller 104 that forms a single closed PID control loop with the heating element 76 and thermistor 94 .

[0032] As an alternative to heating elements and thermistors, the detector sensor assembly 20 may utilize a semiconductor device as the temperature regulating device 51 that is configured to act as a positive temperature coefficient (PTC) heater to maintain a consistent temperature across the photodiode array 54 . Figures 7 to 9is a different schematic diagram of the side of the detector sensor assembly 20 having a PTC heater 114 as a temperature regulating device 51. The PTC heater 114 is configured to self-regulate its temperature to a certain set point. Specifically, the PTC heater 114 increases its resistance at temperatures above a certain level and is able to maintain a constant heating element temperature during load and supply voltage changes. Therefore, the PTC heater 114 is not externally controlled. Figure 7 As shown, the PTC heater 114 is a thin flexible layer disposed between the photodiode array 54 and the portion 68 of the flexible circuit 58. The PTC heater 114 may include holes for forming a diode connection. Figure 8 As shown, the PTC heater 114 is a thin flexible layer disposed between the portion 68 of the flexible circuit 58 and the thermal isolation layer 66. Fig. 9 As shown, the PTC heater 114 is integrated into the portion 68 of the flexible circuit 58. Fig.10 As shown, the PTC heater 114 is powered by two conductors 116 , 118 in the flexible circuit 58 .

[0033] Technical effects of the disclosed embodiments include providing a temperature regulation system that provides temperature regulation for individual detector elements or sensors (e.g., via local control and feedback). In certain embodiments, the temperature regulation system includes an individual temperature regulation device associated with each individual detector element that maintains a consistent temperature across the photodiode array of the detector element. The temperature regulation system can enable a faster thermal response of the entire detector, which corresponds to a faster time for the entire CT system to be ready for acquisition. In addition, the temperature regulation system provides a lower cost thermal solution than a typical cooling system.

[0034] This written description uses examples to disclose the subject matter, including the best mode, and also to enable those skilled in the art to practice the present methods, including making and using any devices or systems and performing any included methods. The patent scope is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to fall within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insignificant differences from the literal language of the claims.

Claims

1. A detector assembly (15) positionable to receive X-rays from an X-ray source (14) within an imaging system (10), the detector assembly (15) comprising: a plurality of detector elements (20); and A temperature regulation system (50), the temperature regulation system comprising a plurality of temperature regulation devices (51), wherein each temperature regulation device (51) of the plurality of temperature regulation devices (51) is associated with a corresponding detector element (20) of the plurality of detector elements (20), and each temperature regulation device (51) is configured to independently maintain a uniform temperature over a portion of the corresponding detector element (51), Each detector element (20) includes a thermal isolation layer (66) disposed between the photodiode array (54) and the thermal shunt (64) and configured to thermally isolate the electronic device (56) and the thermal shunt (64) from the photodiode array (54).

2. The detector assembly (15) of claim 1, wherein each detector element (20) of the plurality of detector elements (20) comprises: a scintillator array (52) configured to convert X-rays into lower energy photons; The photodiode array (54) is configured to convert the photons into analog electrical signals; the electronic device (56) is configured to receive the analog electrical signals and convert the analog electrical signals into digital signals; and a flexible circuit (58) coupled to both the photodiode array (54) and the electronic device (56) and configured to provide the analog electrical signal to the electronic device (56).

3. The detector assembly (15) of claim 2, wherein each detector element (20) includes the thermal shunt (64) coupled to the electronic device (56) and configured to receive heat generated by the electronic device (56), and a portion of the flexible circuit (58) is disposed between the photodiode array (54) and the thermal isolation layer (66).

4. The detector assembly (15) of claim 3, wherein each of the plurality of temperature regulating devices (51) is configured to maintain a consistent temperature across the photodiode array (54).

5. The detector assembly (15) of claim 4, wherein each temperature regulating device (51) comprises a plurality of heating elements (76) disposed within the portion of the flexible circuit (58), each temperature regulating device (51) comprises a plurality of thermistors (94) disposed within the flexible circuit (58), wherein a corresponding thermistor (94) of the plurality of thermistors (94) is coupled to a corresponding heating element (76) of the plurality of heating elements (76), and each corresponding thermistor (94) is configured to provide temperature feedback to the corresponding heating element (76).

6. The detector assembly (15) of claim 5, wherein the plurality of heating elements (76) comprises a plurality of resistor arrays (80).

7. The detector assembly (15) of claim 5, wherein each detector element (20) comprises a control circuit (102) coupled to the plurality of heating elements (76) and the plurality of thermistors (94), wherein the control circuit (102) is configured to control the plurality of heating elements (76) to a specific set temperature point and receive the temperature feedback from the plurality of thermistors (94).

8. The detector assembly (15) of claim 7, wherein the control circuit (102) is configured to control the plurality of heating elements (76) using one or more proportional-integral-derivative control loops.

9. The detector assembly (15) of claim 7, wherein the plurality of heating elements (76) include a first heating element (82, 84) and a second heating element (86), the first heating elements (82, 84) being located near an edge (88, 90) of the portion of the flexible circuit (58), and the second heating element (86) being located at a center within the portion of the flexible circuit (58), and the control circuit (102) being configured to control the first heating elements (82, 84) to a first temperature and to control the second heating element (86) to a second temperature different from the first temperature.

10. The detector assembly (15) of claim 4, wherein each temperature regulating device (51) comprises a semiconductor device configured to act as a positive temperature coefficient heater (114), the positive temperature coefficient heater being configured to self-regulate the temperature of the positive temperature coefficient heater (114).

11. The detector assembly (15) of claim 10, wherein the positive temperature coefficient heater (114) is disposed between the photodiode array (54) and the flexible circuit (58) or between the photodiode array (54) and the thermal isolation layer (66).

12. The detector assembly (15) of claim 10, wherein the positive temperature coefficient heater (114) is integrated within the portion of the flexible circuit (58).

13. The detector assembly (15) of claim 3, comprising a heat diffusion layer (74) disposed between the portion of the flexible circuit (58) and the thermal isolation layer (66).

14. The detector assembly (15) of claim 1, wherein the detector assembly (15) comprises a CT detector assembly for a CT imaging system (10).

15. A CT system (10), comprising: a frame (12) having an opening (48) for receiving an object to be scanned; an X-ray source (14) attached to the gantry (12) and configured to emit X-rays through the opening (48); and a detector assembly (15) attached to the gantry (12) and configured to receive the X-rays, wherein the detector assembly (15) comprises: A detector element (20), the detector element comprising: a scintillator array (52) configured to convert X-rays into lower energy photons; a photodiode array (54) configured to convert the photons into analog electrical signals; an electronic device (56) configured to receive the analog electrical signal and convert the analog electrical signal into a digital signal; and a flexible circuit (58) coupled to both the photodiode array (54) and the electronics (56) and configured to provide the analog electrical signal to the electronics (56); a heat shunt (64) coupled to the electronic device (56) and configured to receive heat generated by the electronic device (56); a thermal isolation layer (66) disposed between the photodiode array (54) and the thermal shunt (64) and configured to thermally isolate the electronic device (56) and the thermal shunt (64) from the photodiode array (54), wherein a portion of the flexible circuit (58) is disposed between the photodiode array (54) and the thermal isolation layer (66); and A temperature regulator (51) is coupled to the detector element (20) and is configured to maintain a consistent temperature across the photodiode array (54).

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