Method, device, equipment and medium for controlling detector temperature in CT system

Abstract

The present disclosure provides a method, device, equipment and medium for controlling the temperature of a detector in a CT system, including: when the CT system is at a preset ambient temperature, adjusting the temperature control of the detector; obtaining infrared image data collected by an infrared imaging sensor and including the entire surface of the detector; determining the temperature data distribution representation corresponding to the detector based on the infrared image data and the pixel temperature value collected by each temperature sensor, the temperature data distribution representation is used to describe the temperature gradient information of the detector; based on the temperature gradient information of the detector, performing temperature compensation on the detection unit corresponding to the corresponding pixel point. Thus, through the infrared imaging sensor and multiple temperature sensors, the current temperature value of each pixel point in the detector can be effectively identified, so that the corresponding point position can be locally heated or cooled in time to adjust the temperature uniformity of the entire detector, effectively solving the problem of image artifacts or non-uniformity, and thus improving the image quality.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to the field of temperature control technology, and in particular, to a method, device, equipment, and medium for controlling the temperature of a detector in a CT system. Background Art

[0002] The detector is the core component of the CT (Computerized Tomography) system. Its function is to capture the intensity of the X-rays emitted by the radiation source and passing through the patient, which can be used by the CT system to reconstruct the tomographic image of the patient's body. The design and performance of the detector in the CT system are crucial to obtaining high-quality tomographic images.

[0003] The detector in the CT system needs to maintain a stable ambient temperature during operation to ensure accurate and reliable imaging results. However, the detector in the CT system is usually composed of multiple detection units. There will be large temperature differences between the detection units during the operation of the CT system, making the temperature of each detection unit uneven, causing image artifacts or unevenness, and seriously affecting the image quality. Summary of the invention

[0004] The embodiments described herein provide a method, device, apparatus, and medium for controlling the temperature of a detector in a CT system, which overcome the above-mentioned problems.

[0005] In a first aspect, according to the present disclosure, a method for controlling the temperature of a detector in a CT system is provided, wherein the CT system is provided with an infrared imaging sensor and a plurality of temperature sensors, the infrared imaging sensor and the plurality of temperature sensors are respectively arranged at different positions of a rotating frame, one temperature sensor corresponds to a detection area of ​​the detector, and one temperature sensor is used to detect a temperature value of a pixel point in the corresponding detection area;

[0006] include:

[0007] When the CT system is at a preset ambient temperature, the detector is temperature-controlled and adjusted so that the average temperature of different pixel points collected by the plurality of temperature sensors is within a preset range of the detector target temperature;

[0008] Acquire infrared image data collected by the infrared imaging sensor and including the entire surface of the detector;

[0009] Based on the infrared image data and the pixel temperature value collected by each temperature sensor, determine the temperature data distribution representation corresponding to the detector, the temperature data distribution representation is used to describe the temperature gradient information of the detector, the temperature gradient information corresponds to a four-tuple data value, and the four-tuple data value includes: the two-dimensional position coordinates of each pixel point in the detector, the infrared temperature difference value of each pixel point and the actual temperature value of each pixel point;

[0010] Based on the temperature gradient information of the detector, temperature compensation is performed on the detection unit corresponding to the corresponding pixel point.

[0011] In a second aspect, according to the content of the present disclosure, a device for controlling the temperature of a detector in a CT system is provided, wherein the CT system is provided with an infrared imaging sensor and a plurality of temperature sensors, the infrared imaging sensor and the plurality of temperature sensors are respectively arranged at different positions of a rotating frame, one temperature sensor corresponds to a detection area of ​​the detector, and one temperature sensor is used to detect a temperature value of a pixel point in the corresponding detection area;

[0012] include:

[0013] An adjustment module, configured to perform temperature control adjustment on the detector when the CT system is at a preset ambient temperature, so that the temperature averages of different pixel points collected by the plurality of temperature sensors are within a preset range of the detector target temperature;

[0014] An acquisition module, used to acquire infrared image data including the entire surface of the detector collected by the infrared imaging sensor;

[0015] A determination module, configured to determine a temperature data distribution representation corresponding to the detector based on the infrared image data and the pixel temperature value collected by each of the temperature sensors, wherein the temperature data distribution representation is used to describe the temperature gradient information of the detector, and the temperature gradient information corresponds to a four-tuple data value, wherein the four-tuple data value includes: a two-dimensional position coordinate of each pixel point in the detector, an infrared temperature difference value of each pixel point, and an actual temperature value of each pixel point;

[0016] The compensation module is used to perform temperature compensation on the detection unit corresponding to the corresponding pixel point based on the temperature gradient information of the detector.

[0017] In a third aspect, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the steps of the method for controlling the temperature of a detector in a CT system in any of the above embodiments are implemented.

[0018] In a fourth aspect, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method for controlling the temperature of a detector in a CT system in any of the above embodiments are implemented.

[0019] The embodiment of the present application provides a method for controlling the temperature of a detector in a CT system, wherein an infrared imaging sensor and a plurality of temperature sensors are provided in the CT system, the infrared imaging sensor and the plurality of temperature sensors are respectively provided at different positions of a rotating frame, a temperature sensor corresponds to a detection area of ​​the detector, and a temperature sensor is used to detect the temperature value of a pixel point in the corresponding detection area; the method comprises: when the CT system is at a preset ambient temperature, adjusting the temperature control of the detector so that the temperature averages of different pixel points collected by the plurality of temperature sensors are within a preset range of the target temperature of the detector; acquiring infrared image data collected by the infrared imaging sensor and including the entire surface of the detector; determining a temperature data distribution representation corresponding to the detector based on the infrared image data and the pixel temperature value collected by each temperature sensor, the temperature data distribution representation being used to describe the temperature gradient information of the detector, the temperature gradient information corresponding to a four-tuple data value, the four-tuple data value comprising: a two-dimensional position coordinate of each pixel point in the detector, an infrared temperature difference of each pixel point, and an actual temperature value of each pixel point; and performing temperature compensation on the detection unit corresponding to the corresponding pixel point based on the temperature gradient information of the detector. In this way, the current temperature value of each pixel in the detector can be effectively identified through infrared imaging sensors and multiple temperature sensors, which facilitates timely local heating or cooling of the corresponding point position to adjust the temperature uniformity of the entire detector, effectively solving the problem of image artifacts or unevenness, and thus improving image quality.

[0020] The above description is only an overview of the technical solution of the embodiment of the present application. In order to more clearly understand the technical means of the embodiment of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly described below. It should be noted that the drawings described below only relate to some embodiments of the present disclosure, but are not intended to limit the present disclosure, wherein:

[0022] Figure 1 It is a flow chart of a method for controlling the temperature of a detector in a CT system provided by the present disclosure.

[0023] Figure 2 It is a schematic diagram of the relative position relationship between a temperature sensor and a detector provided by the present invention.

[0024] Figure 3 It is a geometric diagram of setting parameters of a detector provided by the present invention.

[0025] Figure 4 It is a structural schematic diagram of a detector temperature control device in a CT system provided by the present disclosure.

[0026] Figure 5 It is a structural schematic diagram of a computer device provided by the present disclosure.

[0027] It should be noted that the elements in the drawings are schematic and not drawn to scale. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without creative work also fall within the scope of protection of the present disclosure.

[0029] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by a person skilled in the art to which the subject matter of the present disclosure belongs. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the specification and the relevant art, and will not be interpreted in an idealized or overly formal form unless otherwise explicitly defined herein. As used herein, a statement that two or more parts are "connected" or "coupled" together shall mean that the parts are joined together directly or through one or more intermediate components.

[0030] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase "embodiments" in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0031] The term "and / or" in this article is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship. Terms such as "first" and "second" are only used to distinguish one component (or a part of a component) from another component (or another part of a component).

[0032] In the description of the present application, unless otherwise specified, "plurality" means more than two (including two), and similarly, "multiple groups" means more than two groups (including two).

[0033] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings.

[0034] Figure 1 It is a flow chart of a method for controlling the temperature of a detector in a CT system provided by an embodiment of the present disclosure. An infrared imaging sensor and multiple temperature sensors are provided in the CT system. The infrared imaging sensor and the multiple temperature sensors are respectively arranged at different positions of a rotating frame. One temperature sensor corresponds to one detection area of ​​the detector, and one temperature sensor is used to detect the temperature value of a pixel point in the corresponding detection area.

[0035] The detectors are distributed in an arc-shaped structure, and as the rotating frame rotates, the infrared imaging sensor and multiple temperature sensors are located on the rotating frame. Specifically, the infrared imaging sensor can be located above the detector and diagonally opposite to the detector (i.e., diagonally above). Since the tube and the detector are directly opposite, the infrared imaging sensor is diagonally opposite, and the system structure satisfies that the sensor imaging spectrum range must cover the entire detector surface.

[0036] In order to meet the capability and conditions of the infrared imaging sensor to detect temperature, the housing above the detector position may be designed to be a material that can transmit infrared waves (such as a transparent plastic material).

[0037] Due to the high complexity and integration of the detector, it is not suitable to cover the entire detector with a large number of temperature sensors. In this embodiment, three temperature sensors are used to collect the temperatures at three locations as the reference for infrared sensing temperature. Figure 2 As shown, three temperature sensors (TS1, TS2, TS3) are equidistantly distributed on the rotating frame below the detector, close to the surface below the detector, so as to accurately detect the temperature.

[0038] The temperature sensor is used to detect the temperature information of a specific position on the detector surface in real time and accurately, and to infer the temperature distribution of the entire detector based on the temperature information at the specific position. In this embodiment, three temperature sensors are selected to detect the local temperature, which are located at the center of the detector near the left, middle, and right sides of the detector respectively; the infrared imaging sensor is used to detect the infrared spectrum information of the entire surface of the detector in real time, and the temperature value of any position of the entire detector is inferred based on the entire infrared spectrum information and the specific position information of the temperature sensor.

[0039] like Figure 1 As shown, the specific process of the method for controlling the temperature of the detector in the CT system includes:

[0040] S110. When the CT system is at a preset ambient temperature, temperature control of the detector is adjusted.

[0041] The preset ambient temperature may be the ambient temperature of the CT system in the working state pre-set by the CT subsystem ambient temperature control system (TCS1), for example, the preset ambient temperature Te may be set to 24 degrees.

[0042] When the CT system is at a preset ambient temperature, the detector is temperature-controlled and adjusted so that the average temperature of different pixel points collected by multiple temperature sensors is within the preset range of the detector target temperature. The detector target temperature can be a measured temperature preset by the detector temperature control system (TCS2), such as the detector target temperature T 0 The temperature deviation range is defined as [-1, +1] temperature values, and the preset range of the detector target temperature is [29, 31] temperature values.

[0043] Temperature control adjustment is used to increase or decrease the ambient temperature of the CT system. For example, if the average temperature of different pixel points collected by the three temperature sensors is less than the minimum value in the preset range of the detector target temperature (i.e., 29 degrees), the temperature of the CT system environment is increased; if the average temperature of different pixel points collected by the three temperature sensors is greater than the maximum value in the preset range of the detector target temperature (i.e., 31 degrees), the temperature of the CT system environment is decreased.

[0044] Both the ambient temperature control system (TCS1) and the detector temperature overall control system (TCS2) adopt PID control algorithm, as shown in the following formula (1).

[0045]

[0046] In formula (1), K P is the proportional gain, which can be adjusted; K i K is the integral gain, which can be adjusted; dis the differential gain, which can be adjusted; e is the error, e=SP (set value)-PV (output value); t is the current time.

[0047] S120: Acquire infrared image data including the entire surface of the detector collected by the infrared imaging sensor.

[0048] Among them, the infrared image data can be the scene infrared Raw data including the entire detector surface. It can be understood that the infrared image data includes both the Raw data of the entire detector surface and the Raw data outside the detector surface, that is, the infrared image data including the entire detector surface collected by the infrared imaging sensor includes: the Raw data of the detector surface and the Raw data outside the detector.

[0049] In addition, considering the mutual influence of infrared and X-rays, this embodiment suspends the image acquisition of the infrared imaging sensor during the X-ray generation period of the CT system, and the infrared imaging sensor is in a suspended working state during this period. The rotation of the CT system also causes trouble to infrared imaging, so the infrared imaging sensor can also be switched to a suspended working state during the rotation. That is, during the rotation pause period during the CT system scanning process, the infrared imaging sensor can start working.

[0050] S130 , determining a temperature data distribution representation corresponding to the detector based on the infrared image data and the pixel temperature value collected by each temperature sensor.

[0051] Among them, the temperature data distribution representation is used to describe the temperature gradient information of the detector. The temperature gradient information corresponds to a four-tuple data value, which includes: the two-dimensional position coordinates of each pixel point in the detector, the infrared temperature difference of each pixel point, and the actual temperature value of each pixel point.

[0052] It should be noted that the actual temperature value of each pixel point referred to in this embodiment is not the real temperature value tested by the device, but a relatively accurate temperature value obtained after calibration of the inferred estimated temperature value of each pixel point.

[0053] The infrared temperature difference of each pixel point is determined by the scaled detector spectrum data. The scaled detector spectrum data is obtained by proportionally scaling the restored detector spectrum data through the set parameters of the detector. The restored detector spectrum data is obtained by relative position restoration of the segmented detector spectrum data. The segmented detector spectrum data is obtained by image segmentation processing of the infrared spectrum data. The infrared spectrum data is obtained by range mapping based on the infrared image data.

[0054] The actual temperature value of each pixel is determined by the sum of the estimated temperature value of the corresponding pixel and the temperature calibration value. The temperature calibration value corresponding to the pixel is obtained by the corresponding estimated temperature value and the pixel temperature value collected by multiple temperature sensors. The estimated temperature value corresponding to the pixel is determined by the corresponding infrared temperature difference and the detector target temperature.

[0055] In some embodiments, determining a temperature data distribution representation corresponding to the detector based on the infrared image data and the pixel temperature value collected by each temperature sensor includes:

[0056] The infrared image data is normalized to generate infrared floating-point data corresponding to a preset mapping range; the mapping range is adjusted based on the infrared floating-point data corresponding to the preset mapping range to obtain infrared spectrum data; the infrared spectrum data is segmented to obtain segmented detector spectrum data; based on the segmented detector spectrum data and the pixel temperature value collected by each temperature sensor, a temperature data distribution representation corresponding to the detector is constructed.

[0057] For example, the preset mapping range can be [0,1]. The infrared Raw data is linearly normalized to generate infrared floating-point data mapped to the range [0,1]. The infrared floating-point data is generated into infrared spectrum data in the range [-32,768, 32,767] (i.e., 16-bit data). The 16-bit infrared spectrum data has a deviation value with a description accuracy of 1 / 1000.

[0058] The infrared spectrum data may include: detector spectrum data and background spectrum data. The detector spectrum data is spectrum data mapped from the Raw data on the detector surface, and the background spectrum data is spectrum data mapped from the Raw data outside the detector.

[0059] The normalization process can be implemented using the following formula (2).

[0060]

[0061] In formula (2), max(x) is the maximum value in the heat map of the image data; min(x) is the minimum value in the heat map of the image data; x' is the data value after linear normalization, x'∈[0,1].

[0062] Thus, the infrared spectrum data after the infrared imaging sensor data processing is subjected to image processing so as to segment the detector spectrum data from the scene data, and the temperature data distribution map of the entire detector is constructed in combination with the temperatures of the three temperature sensors.

[0063] In some embodiments, performing image segmentation processing on the infrared spectrum data to obtain segmented detector spectrum data includes:

[0064] Based on the temperature difference between the preset ambient temperature and the target temperature of the detector, an edge segmentation algorithm is used to mark the regional position of the detector from the infrared spectrum data; data extraction is performed on the spectrum data corresponding to the regional position of the detector in the infrared spectrum data to obtain segmented detector spectrum data.

[0065] For example, based on the preset ambient temperature (Te) and the detector target temperature (T 0 ), the edge-based segmentation algorithm of OpenCV can be used to mark the area where the detector is located in the infrared spectrum data, so that the detector part of the spectrum data can be accurately segmented. In this embodiment, a threshold method can be used to distinguish between background spectrum data and detector spectrum data.

[0066] In some embodiments, based on the segmented detector atlas data and the pixel temperature values ​​collected by each temperature sensor, a temperature data distribution representation corresponding to the detector is constructed, including:

[0067] The segmented detector map data is restored to relative position to obtain the estimated temperature value of each pixel in the detector; the actual temperature value of each pixel in the detector is determined based on the estimated temperature value of each pixel in the detector and the pixel temperature value collected by each temperature sensor; the temperature gradient information of the detector is obtained based on the two-dimensional position coordinates of each pixel, the actual temperature value of each pixel and the infrared temperature difference of each pixel.

[0068] The four-tuple data value corresponding to the temperature gradient information of the detector includes: the two-dimensional position coordinates of each pixel in the detector, the infrared temperature difference of each pixel, and the actual temperature value of each pixel, which can be expressed as [PR i 、PC j 、T dk 、T ri ], PR i Represents the horizontal coordinate of the pixel, PC j Represents the vertical coordinate of the pixel, T dk is the infrared temperature difference of a pixel, T ri is the actual temperature value of a pixel.

[0069] In some embodiments, the segmented detector map data is map data when the infrared imaging sensor and the detector are in an oblique viewing relationship.

[0070] Relative position restoration is performed on the segmented detector atlas data to obtain the estimated temperature value of each pixel in the detector, including:

[0071] The segmented detector map data is relatively restored to obtain the restored detector map data, so as to perform relative position correction on the segmented detector map data; based on the set parameters of the detector, the restored detector map data is proportionally scaled to obtain the estimated temperature value of each pixel in the detector.

[0072] Among them, since the infrared imaging sensor and the detector are in an oblique viewing relationship, the transmission transformation algorithm of OpenCV can be used to restore the spectrum data. The restored spectrum data is the spectrum data of the forward viewing relationship, that is, the restored detector spectrum data is the spectrum data under the forward viewing relationship between the infrared imaging sensor and the detector.

[0073] The setting parameters of the detector include: the length of the detector in a first axial direction and the arc length of the detector in a second axial direction, and the first axial direction is perpendicular to the second axial direction.

[0074] For example, the first axis may be the X axis in the three-dimensional coordinate system, and the second axis may be the Z axis in the three-dimensional coordinate system. The entire detector surface forms an arc-shaped rectangle, and the setting parameter of the detector is D a , D b , D a Indicates the value of the detector in the X-axis direction (unit: mm), D b Indicates the arc length of the detector in the Z-axis direction (unit: mm).

[0075] Also, see Figure 3 As shown, D b Its value can also be obtained by the following formula (3).

[0076]

[0077] In some embodiments, based on the set parameters of the detector, the restored detector map data is scaled proportionally to obtain the estimated temperature value of each pixel in the detector, including:

[0078] Based on the set parameters of the detector, the restored detector map data is scaled proportionally to obtain scaled detector map data so that the scaled detector map data matches the parameters of the detector; based on the scaled detector map data, the infrared temperature difference of each pixel in the detector is determined; based on the infrared temperature difference of each pixel and the target temperature of the detector, the estimated temperature value of each pixel in the detector is determined.

[0079] The output spectrum data of the transmission transformation (i.e., the restored detector spectrum data) is scaled to the actual size D of the detector using the OpenCV transmission transformation algorithm. a , D b Spectral data with equal proportions (i.e. scaled detector spectral data).

[0080] The infrared temperature difference of each pixel is used to describe the difference between the infrared temperature value of the corresponding pixel in the scaled detector map data and the infrared temperature value of the mapping reference point of the corresponding pixel in the scaled detector map data. The mapping reference point is a pixel detected by the corresponding temperature sensor in the detection area to which it belongs.

[0081] For example, when determining the infrared temperature difference of pixel point A in the detector, the infrared temperature value corresponding to the pixel point in the scaled detector map data is the infrared temperature value corresponding to pixel point A in the scaled detector map data.

[0082] The mapping reference point of pixel A is the pixel detected by the detection temperature sensor of the detector to which pixel A belongs. For example, in this embodiment, three temperature sensors (TS1, TS2, and TS3) are used for local temperature detection. TS1 detects pixel B1 of one detection unit in the left detection area of ​​the detector, TS1 detects pixel B2 of one detection unit in the middle detection area of ​​the detector, and TS1 detects pixel B3 of one detection unit in the right detection area of ​​the detector. When pixel A is located in the left detection area in the detector, the mapping reference point of pixel A is pixel B1. The mapping reference point of the pixel corresponds to the infrared temperature value in the scaled detector map data, that is, the infrared temperature value corresponding to pixel B1 in the scaled detector map data.

[0083] When determining the estimated temperature value of each pixel in the detector based on the infrared temperature difference of each pixel and the detector target temperature, the following formula (4) can be used to determine it.

[0084]

[0085] In formula (4), T 0 is the detector target temperature, T dk is the infrared temperature difference of a pixel.

[0086] Therefore, by proportionally scaling the restored detector map data to match the scaled detector map data with the detector parameters, the infrared temperature difference of each pixel in the detector is determined based on the scaled detector map data, thereby effectively determining the estimated temperature value of each pixel in the detector.

[0087] In some embodiments, determining the actual temperature value of each pixel in the detector based on the estimated temperature value of each pixel in the detector and the pixel temperature value collected by each temperature sensor includes:

[0088] Based on the estimated temperature value of each pixel in the detector and the pixel temperature value collected by each temperature sensor, the corresponding temperature calibration value is determined; based on the temperature calibration value corresponding to each pixel and the estimated temperature value corresponding to each pixel, the actual temperature value of the corresponding pixel is determined.

[0089] The temperature calibration value is used to describe the difference between the estimated temperature value and the actual temperature value.

[0090] For example, the temperature difference of the temperature sensor TS1, the temperature difference of the temperature sensor TS2, and the temperature difference of the temperature sensor TS3 are shown in the following formula (5).

[0091]

[0092] In formula (5), T 1x is the temperature difference of temperature sensor TS1; T 1 is the pixel temperature value collected by the temperature sensor TS1; T ii is the estimated temperature value corresponding to the corresponding pixel point; T 2x is the temperature difference of temperature sensor TS2; T 2 is the pixel temperature value collected by the temperature sensor TS2; T 3x is the temperature difference of temperature sensor TS3; T 3 It is the pixel temperature value collected by the temperature sensor TS3.

[0093] Temperature calibration value T x As shown in the following formula (6).

[0094]

[0095] The actual temperature value of a pixel is the sum of the temperature calibration value corresponding to the pixel and the estimated temperature value corresponding to the pixel. The actual temperature value is shown in the following formula (7).

[0096] T ri =T ii +T x (7)

[0097] Thus, the corresponding temperature calibration value is determined through the estimated temperature value of each pixel in the detector and the pixel temperature value collected by each temperature sensor, so as to perform temperature calibration on the estimated temperature value and effectively obtain the actual temperature value corresponding to each pixel.

[0098] S140 , performing temperature compensation on the detection unit corresponding to the corresponding pixel point based on the temperature gradient information of the detector.

[0099] When performing detector temperature compensation, compensation can be performed in a local area, such as increasing or decreasing the temperature of the detection unit corresponding to the corresponding pixel, or increasing or decreasing the temperature of the detection area to which the detection unit corresponding to the corresponding pixel belongs. This facilitates the temperature local control system (TCS3) to accurately control and compensate the layout temperature based on temperature data.

[0100] This embodiment uses an infrared imaging sensor to collect infrared spectra on the detector surface and analyzes the heat distribution to identify locations where the detector temperature deviation is large, so that the temperature control system can perform local heating or cooling treatment on these locations to achieve uniform temperature adjustment of the entire detector.

[0101] In this embodiment, an infrared imaging sensor and a plurality of temperature sensors are provided in the CT system, and the infrared imaging sensor and the plurality of temperature sensors are respectively provided at different positions of the rotating frame, a temperature sensor corresponds to a detection area of ​​the detector, and a temperature sensor is used to detect the temperature value of a pixel point in the corresponding detection area; including: when the CT system is at a preset ambient temperature, temperature control adjustment is performed on the detector so that the temperature averages of different pixel points collected by the plurality of temperature sensors are within a preset range of the target temperature of the detector; infrared image data collected by the infrared imaging sensor and including the entire surface of the detector are obtained; based on the infrared image data and the pixel temperature value collected by each temperature sensor, a temperature data distribution representation corresponding to the detector is determined, the temperature data distribution representation is used to describe the temperature gradient information of the detector, the temperature gradient information corresponds to a four-tuple data value, and the four-tuple data value includes: the two-dimensional position coordinates of each pixel point in the detector, the infrared temperature difference of each pixel point, and the actual temperature value of each pixel point; based on the temperature gradient information of the detector, temperature compensation is performed on the detection unit corresponding to the corresponding pixel point. In this way, the current temperature value of each pixel in the detector can be effectively identified through infrared imaging sensors and multiple temperature sensors, which facilitates timely local heating or cooling of the corresponding point position to adjust the temperature uniformity of the entire detector, effectively solving the problem of image artifacts or unevenness, and thus improving image quality.

[0102] Figure 4 A schematic diagram of the structure of a detector temperature control device in a CT system provided in this embodiment, wherein an infrared imaging sensor and a plurality of temperature sensors are provided in the CT system, and the infrared imaging sensor and the plurality of temperature sensors are respectively provided at different positions of a rotating frame, one temperature sensor corresponds to one detection area of ​​the detector, and one temperature sensor is used to detect the temperature value of a pixel point in the corresponding detection area.

[0103] The device for controlling the temperature of the detector in the CT system may include: an adjustment module 410 , an acquisition module 420 , a determination module 430 and a compensation module 440 .

[0104] The adjustment module 410 is used to perform temperature control adjustment on the detector when the CT system is at a preset ambient temperature, so that the temperature averages of different pixel points collected by multiple temperature sensors are within a preset range of the detector target temperature.

[0105] The acquisition module 420 is used to acquire infrared image data including the entire surface of the detector collected by the infrared imaging sensor.

[0106] Determination module 430 is used to determine the temperature data distribution representation corresponding to the detector based on the infrared image data and the pixel temperature value collected by each temperature sensor. The temperature data distribution representation is used to describe the temperature gradient information of the detector. The temperature gradient information corresponds to a four-tuple data value. The four-tuple data value includes: the two-dimensional position coordinates of each pixel point in the detector, the infrared temperature difference of each pixel point, and the actual temperature value of each pixel point.

[0107] The compensation module 440 is used to perform temperature compensation on the detection unit corresponding to the corresponding pixel point based on the temperature gradient information of the detector.

[0108] In this embodiment, optionally, the determination module 430 includes: a generation unit, an adjustment unit, a processing unit and a construction unit.

[0109] The generating unit is used to perform normalization processing on the infrared image data to generate infrared floating point data corresponding to a preset mapping range.

[0110] The adjustment unit is used to adjust the mapping range based on the infrared floating-point data corresponding to the preset mapping range to obtain infrared spectrum data.

[0111] The processing unit is used to perform image segmentation processing on the infrared spectrum data to obtain segmented detector spectrum data.

[0112] The construction unit is used to construct a temperature data distribution representation corresponding to the detector based on the segmented detector atlas data and the pixel temperature value collected by each temperature sensor.

[0113] In this embodiment, optionally, the construction unit is specifically used for:

[0114] The segmented detector map data is restored to relative position to obtain the estimated temperature value of each pixel in the detector; the actual temperature value of each pixel in the detector is determined based on the estimated temperature value of each pixel in the detector and the pixel temperature value collected by each temperature sensor; the temperature gradient information of the detector is obtained based on the two-dimensional position coordinates of each pixel, the actual temperature value of each pixel and the infrared temperature difference of each pixel.

[0115] In this embodiment, optionally, the segmented detector map data is map data when the infrared imaging sensor and the detector are in an oblique viewing relationship.

[0116] Building blocks, specifically for:

[0117] The segmented detector map data is relatively restored to obtain the restored detector map data, so as to perform relative position correction on the segmented detector map data. The restored detector map data is the map data when the infrared imaging sensor and the detector are in a positive viewing relationship. Based on the setting parameters of the detector, the restored detector map data is proportionally scaled to obtain the estimated temperature value of each pixel in the detector. The setting parameters of the detector include: the length of the detector in the first axis and the arc length of the detector in the second axis, and the first axis is perpendicular to the second axis.

[0118] In this embodiment, optionally, the construction unit is specifically used for:

[0119] Based on the set parameters of the detector, the restored detector map data is scaled proportionally to obtain the scaled detector map data so that the scaled detector map data matches the parameters of the detector; based on the scaled detector map data, the infrared temperature difference of each pixel in the detector is determined, and the infrared temperature difference of each pixel is used to describe the difference between the infrared temperature value of the corresponding pixel in the scaled detector map data and the infrared temperature value of the mapping reference point of the corresponding pixel in the scaled detector map data, and the mapping reference point is a pixel detected by the corresponding temperature sensor in the detection area to which it belongs; based on the infrared temperature difference of each pixel and the target temperature of the detector, the estimated temperature value of each pixel in the detector is determined.

[0120] In this embodiment, optionally, the construction unit is specifically used for:

[0121] Based on the estimated temperature value of each pixel in the detector and the pixel temperature value collected by each temperature sensor, the corresponding temperature calibration value is determined; based on the temperature calibration value corresponding to each pixel and the estimated temperature value corresponding to each pixel, the actual temperature value of the corresponding pixel is determined.

[0122] In this embodiment, optionally, the processing unit is specifically configured to:

[0123] Based on the temperature difference between the preset ambient temperature and the target temperature of the detector, an edge segmentation algorithm is used to mark the regional position of the detector from the infrared spectrum data; data extraction is performed on the spectrum data corresponding to the regional position of the detector in the infrared spectrum data to obtain segmented detector spectrum data.

[0124] The device for controlling the temperature of a detector in a CT system provided in the present disclosure can execute the above method embodiments. Its specific implementation principles and technical effects can be found in the above method embodiments, and the present disclosure will not repeat them here.

[0125] The present application also provides a computer device. Figure 5 , Figure 5 This is a basic structural block diagram of the computer device in this embodiment.

[0126] The computer device includes a memory 510 and a processor 520 that are connected to each other through a system bus. It should be noted that the figure only shows a computer device with a memory 510 and a processor 520, but it should be understood that it is not required to implement all the components shown, and more or fewer components can be implemented instead. Among them, those skilled in the art can understand that the computer device here is a device that can automatically perform numerical calculations and / or information processing according to pre-set or stored instructions, and its hardware includes but is not limited to microprocessors, application specific integrated circuits (Application Specific Integrated Circuit, ASIC), programmable gate arrays (Field-Programmable Gate Array, FPGA), digital processors (Digital Signal Processor, DSP), embedded devices, etc.

[0127] Computer devices can be computing devices such as desktop computers, notebooks, PDAs, and cloud servers. Computer devices can interact with users through keyboards, mice, remote controls, touch pads, or voice control devices.

[0128] The memory 510 includes at least one type of readable storage medium, and the readable storage medium includes a non-volatile memory or a volatile memory, for example, a flash memory, a hard disk, a multimedia card, a card-type memory (for example, an SD or DX memory, etc.), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a magnetic disk, an optical disk, etc., and the RAM may include a static RAM or a dynamic RAM. In some embodiments, the memory 510 may be an internal storage unit of a computer device, for example, a hard disk or a memory of the computer device. In other embodiments, the memory 510 may also be an external storage device of the computer device, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, or a flash card (FlashCard) equipped on the computer device. Of course, the memory 510 may also include both the internal storage unit of the computer device and its external storage device. In this embodiment, the memory 510 is generally used to store the operating system and various application software installed on the computer device, such as the program code of the above method. In addition, the memory 510 may also be used to temporarily store various data that have been output or are to be output.

[0129] The processor 520 is generally used to perform the overall operation of the computer device. In this embodiment, the memory 510 is used to store program codes or instructions, the program code includes computer operation instructions, and the processor 520 is used to execute the program codes or instructions stored in the memory 510 or process data, such as running the program code of the above method.

[0130] In this article, the bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus system can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or one type of bus.

[0131] Another embodiment of the present application also provides a computer-readable medium, which may be a computer-readable signal medium or a computer-readable medium. A processor in a computer reads a computer-readable program code stored in the computer-readable medium, so that the processor can execute the functional actions specified in each step or a combination of steps in the above method; and generate a device for implementing the functional actions specified in each block or a combination of blocks in the block diagram.

[0132] Computer-readable media include but are not limited to electronic, magnetic, optical, electromagnetic, infrared memory or semiconductor systems, devices or apparatuses, or any appropriate combination of the foregoing, the memory is used to store program codes or instructions, the program codes include computer operating instructions, and the processor is used to execute the program codes or instructions of the above methods stored in the memory.

[0133] For the definitions of memory and processor, please refer to the description of the aforementioned computer device embodiment and will not be repeated here.

[0134] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0135] Each functional unit or module in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0136] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) or a processor (processor) to perform all or part of the steps of each embodiment method of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), disk or optical disk and other media that can store program code.

[0137] In the claims, any reference symbols placed between brackets shall not be construed as limiting the claims. The word "comprising" described in the present application does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present application can be implemented with the aid of hardware comprising several different elements and with the aid of a suitably programmed computer. In a unit claim that lists a number of devices, several units of these devices may be embodied by the same hardware item. The use of first, second, and third, etc. does not indicate any order, and these words may be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be understood as limitations on the order of execution.

[0138] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for controlling the temperature of a detector in a CT system, characterized in that: The CT system is provided with an infrared imaging sensor and a plurality of temperature sensors, the infrared imaging sensor and the plurality of temperature sensors are respectively arranged at different positions of the rotating frame, one temperature sensor corresponds to a detection area of ​​the detector, and one temperature sensor is used to detect the temperature value of a pixel point in the corresponding detection area; The method comprises: When the CT system is at a preset ambient temperature, the detector is temperature-controlled and adjusted so that the average temperature of different pixel points collected by the plurality of temperature sensors is within a preset range of the detector target temperature; Acquire infrared image data collected by the infrared imaging sensor and including the entire surface of the detector; Based on the infrared image data and the pixel temperature value collected by each temperature sensor, determine the temperature data distribution representation corresponding to the detector, the temperature data distribution representation is used to describe the temperature gradient information of the detector, the temperature gradient information corresponds to a four-tuple data value, and the four-tuple data value includes: the two-dimensional position coordinates of each pixel point in the detector, the infrared temperature difference value of each pixel point and the actual temperature value of each pixel point; Based on the temperature gradient information of the detector, temperature compensation is performed on the detection unit corresponding to the corresponding pixel point; Wherein, determining the temperature data distribution representation corresponding to the detector based on the infrared image data and the pixel temperature value collected by each temperature sensor includes: Normalizing the infrared image data to generate infrared floating-point data corresponding to a preset mapping range; Adjusting the mapping range based on the infrared floating-point data corresponding to the preset mapping range to obtain infrared spectrum data; Performing image segmentation processing on the infrared spectrum data to obtain segmented detector spectrum data; Based on the segmented detector atlas data and the pixel temperature value collected by each temperature sensor, a temperature data distribution representation corresponding to the detector is constructed.

2. The method according to claim 1, characterized in that The step of constructing a temperature data distribution representation corresponding to the detector based on the segmented detector atlas data and the pixel temperature value collected by each temperature sensor includes: Relative position restoration is performed on the segmented detector atlas data to obtain an estimated temperature value of each pixel in the detector; Determining the actual temperature value of each pixel in the detector based on the estimated temperature value of each pixel in the detector and the pixel temperature value collected by each temperature sensor; The temperature gradient information of the detector is obtained based on the two-dimensional position coordinates of each pixel point, the actual temperature value of each pixel point and the infrared temperature difference value of each pixel point.

3. The method according to claim 2, characterized in that The segmented detector map data is the map data when the infrared imaging sensor and the detector are in an oblique viewing relationship; The relative position restoration of the segmented detector atlas data to obtain an estimated temperature value of each pixel in the detector includes: Relative position restoration is performed on the segmented detector map data to obtain restored detector map data, so as to perform relative position correction on the segmented detector map data, wherein the restored detector map data is map data when the infrared imaging sensor and the detector are in a forward viewing relationship; Based on the setting parameters of the detector, the restored detector map data is scaled proportionally to obtain an estimated temperature value of each pixel in the detector. The setting parameters of the detector include: the length of the detector in a first axial direction and the arc length of the detector in a second axial direction, and the first axial direction is perpendicular to the second axial direction.

4. The method according to claim 3, characterized in that The method of performing data proportional scaling on the restored detector map data based on the set parameters of the detector to obtain an estimated temperature value of each pixel in the detector includes: Based on the set parameters of the detector, scaling the restored detector map data in proportion to obtain scaled detector map data, so that the scaled detector map data matches the parameters of the detector; Based on the scaled detector map data, determining an infrared temperature difference value of each pixel in the detector, the infrared temperature difference value of each pixel being used to describe a difference between an infrared temperature value of the corresponding pixel corresponding to the scaled detector map data and an infrared temperature value of a mapping reference point of the corresponding pixel corresponding to the scaled detector map data, wherein the mapping reference point is a pixel detected by a corresponding temperature sensor in a detection area to which it belongs; Based on the infrared temperature difference of each pixel and the detector target temperature, an estimated temperature value of each pixel in the detector is determined.

5. The method according to claim 2, characterized in that: The determining the actual temperature value of each pixel in the detector based on the estimated temperature value of each pixel in the detector and the pixel temperature value collected by each temperature sensor comprises: Determining a corresponding temperature calibration value based on an estimated temperature value of each pixel in the detector and a pixel temperature value collected by each temperature sensor; Based on the temperature calibration value corresponding to each pixel and the estimated temperature value corresponding to each pixel, the actual temperature value of the corresponding pixel is determined.

6. The method according to claim 1, characterized in that The performing image segmentation processing on the infrared spectrum data to obtain segmented detector spectrum data includes: Based on the temperature difference between the preset ambient temperature and the target temperature of the detector, an edge segmentation algorithm is used to mark the regional position of the detector from the infrared spectrum data; Data extraction is performed on the spectrum data corresponding to the regional position of the detector in the infrared spectrum data to obtain the segmented detector spectrum data.

7. A detector temperature control device in a CT system, characterized in that: The CT system is provided with an infrared imaging sensor and a plurality of temperature sensors, the infrared imaging sensor and the plurality of temperature sensors are respectively arranged at different positions of the rotating frame, one temperature sensor corresponds to a detection area of ​​the detector, and one temperature sensor is used to detect the temperature value of a pixel point in the corresponding detection area; The device comprises: An adjustment module, configured to perform temperature control adjustment on the detector when the CT system is at a preset ambient temperature, so that the temperature averages of different pixel points collected by the plurality of temperature sensors are within a preset range of the detector target temperature; An acquisition module, used to acquire infrared image data including the entire surface of the detector collected by the infrared imaging sensor; A determination module, for determining a temperature data distribution representation corresponding to the detector based on the infrared image data and the pixel temperature value collected by each of the temperature sensors, wherein the temperature data distribution representation is used to describe the temperature gradient information of the detector, and the temperature gradient information corresponds to a four-tuple data value, and the four-tuple data value includes: a two-dimensional position coordinate of each pixel point in the detector, an infrared temperature difference value of each pixel point, and an actual temperature value of each pixel point; the determination module includes: a generation unit, an adjustment unit, a processing unit, and a construction unit; the generation unit is used to perform normalization processing on the infrared image data to generate infrared floating-point data corresponding to a preset mapping range; the adjustment unit is used to perform mapping range adjustment based on the infrared floating-point data corresponding to the preset mapping range to obtain infrared spectrum data; the processing unit is used to perform image segmentation processing on the infrared spectrum data to obtain segmented detector spectrum data; the construction unit is used to construct a temperature data distribution representation corresponding to the detector based on the segmented detector spectrum data and the pixel temperature value collected by each of the temperature sensors; The compensation module is used to perform temperature compensation on the detection unit corresponding to the corresponding pixel point based on the temperature gradient information of the detector.

8. A computer device, characterized in that: The method comprises a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the method for controlling the temperature of a detector in a CT system as claimed in any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for controlling the temperature of a detector in a CT system as claimed in any one of claims 1 to 6 is implemented.

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