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CN-121196588-B - CT detector module with adjustable dip angle and dip angle adjusting method

CN121196588BCN 121196588 BCN121196588 BCN 121196588BCN-121196588-B

Abstract

The invention discloses a tilt angle adjustable CT detector module and a tilt angle adjusting method, comprising a crystal unit, a crystal unit mounting bracket, an adjusting piece and a tilt angle adjusting piece, wherein the crystal unit mounting bracket is provided with a plurality of crystal unit mounting positions, the mounting surface of part of crystal unit mounting positions is provided with a tilt angle, the adjusting piece is arranged at each crystal unit mounting position, the adjusting piece is arranged in two in a first direction and a second direction, and the adjusting piece is used for adjusting the tilt angles of the crystal unit in the first direction and the second direction, and the first direction and the second direction are horizontal and mutually vertical. According to the invention, the inclination angles of the crystal units in the second direction are regulated by the two regulating parts positioned in the second direction, so that the inclination angles of the crystal units in the first direction and the second direction meet the requirements, the consistency of the alignment angles of the anti-scattering grids of the crystal units and X rays is ensured, and therefore, all the crystal units can be ensured to uniformly and efficiently receive X ray signals, signal deviation is reduced, and the accuracy of original data is improved.

Inventors

  • WANG WEI

Assignees

  • 赛诺威盛科技(北京)股份有限公司

Dates

Publication Date
20260508
Application Date
20251118

Claims (9)

  1. 1. A method for tilt angle adjustment of a CT detector module, wherein the CT detector module comprises: A crystal unit; The crystal unit mounting bracket is provided with a plurality of crystal unit mounting positions, and the mounting surface of at least part of the crystal unit mounting positions is provided with an inclination angle; The adjusting piece is arranged at each crystal unit installation position, two adjusting pieces are arranged in the first direction and the second direction on each crystal unit installation position, the adjusting pieces are used for adjusting the inclination angles of the crystal units in the first direction and the second direction, and the first direction and the second direction are horizontal and perpendicular to each other; The inclination angle adjusting method comprises the following steps: acquiring projection data of a CT detector module at a first position and a second position of a bulb tube focus in a first direction, and at a third position and a fourth position in the second direction; Processing and analyzing based on the projection data to obtain the inclination angle adjusting position and the adjusting amount of each crystal unit; and adjusting the crystal unit by adopting the adjusting piece according to the inclination angle adjusting position and the adjusting amount of the crystal unit.
  2. 2. The tilt angle adjustment method of claim 1, wherein the first position and the second position are symmetrical positions with respect to a reference position, the third position and the fourth position are corresponding positions with respect to a reference position, and the reference position is a position when a projection of a bulb focus is located at a center of a field of view of the CT detector module.
  3. 3. The tilt angle adjustment method according to claim 2, wherein the obtaining the tilt angle adjustment position and adjustment amount of each of the crystal units based on the projection data processing analysis includes: Determining a first light response mean vector, a second light response mean vector, a third light response mean vector and a fourth light response mean vector based on the projection data of the first position, the second position, the third position and the fourth position respectively; Acquiring ratio data Rx of the first light response mean vector and the second light response mean vector and ratio data Rz of the third light response mean vector and the fourth light response mean vector; acquiring a projection ratio data average Rnx of each crystal unit based on the ratio data Rx, wherein n represents an nth crystal unit; Acquiring a projection ratio data average Rnz of each crystal unit based on the ratio data Rz, wherein n represents an nth crystal unit; Based on the difference between the mean Rnx and 1 of the projection ratio data of each crystal unit X acquires adjustment reference data Jx in a first direction; Based on the difference between the mean Rnz and 1 of the projection ratio data of each crystal unit Z acquires adjustment reference data Jz in the second direction; the adjustment members in the first direction and the second direction are adjusted based on the adjustment reference data Jx and the adjustment reference data Jz, respectively.
  4. 4. A tilt angle adjustment method according to claim 3, wherein the adjustment reference data Jx comprises an adjustment amount x and an adjustment position dx of the adjustment member in a first direction, and the adjustment reference data Jz comprises an adjustment amount z and an adjustment position dz of the adjustment member in a second direction; Determining the absolute value of the difference value based on the relation between the absolute value of the pre-established difference value and the adjustment quantity The adjustment quantity x corresponding to x| and the absolute value| An adjustment amount z corresponding to z|; when the difference is X is greater than 0, and the adjusting position dx is an adjusting piece close to the first position; when the difference is X is smaller than 0, and the adjusting position dx is an adjusting piece close to the second position; when the difference is Z is greater than 0, the adjustment position dz being an adjustment member near the third position; when the difference is Z is less than 0, the adjustment position dz being the adjustment member near the fourth position.
  5. 5. The tilt angle adjustment method of claim 1, wherein the adjustment member comprises a precision fine adjustment bolt threadedly coupled to the crystal unit mounting bracket, an end face of the precision fine adjustment bolt being adapted to abut a mounting face of the crystal unit to urge the crystal unit to displace.
  6. 6. The tilt angle adjustment method of claim 5, further comprising a scale indicator disposed on a side of the crystal unit mounting bracket facing away from the crystal unit, the scale indicator corresponding to each of the fine precision tooth adjustment bolts to indicate a rotation angle of the fine precision tooth adjustment bolt.
  7. 7. The tilt angle adjustment method of claim 6, wherein the scale indicator comprises a scale indicating label.
  8. 8. The tilt angle adjusting method according to claim 1, wherein the crystal unit mounting position is further provided with a fixing screw hole, and a fixing bolt is screwed into the fixing screw hole, the fixing bolt being used for fixing the crystal unit.
  9. 9. The tilt angle adjustment method of claim 8, wherein the crystal unit mounting location is further provided with a positioning hole, the crystal unit is provided with a positioning piece, and the positioning hole is in plug-in fit with the positioning piece to position the crystal unit; The two fixing screw holes and the two positioning holes are respectively arranged, the two fixing screw holes are symmetrically distributed along the center of the crystal unit installation position, and the two positioning holes are symmetrically distributed along the center of the crystal unit installation position.

Description

CT detector module with adjustable dip angle and dip angle adjusting method Technical Field The invention relates to the technical field of CT equipment, in particular to a CT detector module with an adjustable inclination angle and an inclination angle adjusting method. Background With the continuous development of CT technology, the CT number of rows increases, so that in order to reduce the influence of scattering, the design of an anti-scattering grid of a CT detector has new requirements, a 2D structure grid replaces a traditional 1D structure grid, each grid in the 2D structure needs to be precisely aligned to one pixel of the detector, and the processing and alignment of the anti-scattering grid with high number of rows become a technical difficulty. Mechanically, the CT detector is fan-shaped by a series of detector modules arranged in the X-direction, each module facing the focal point of the bulb. Each detector module is formed by arranging a plurality of crystal units along the Z direction. The anti-scattering grid of the detector is divided into a plurality of independent units according to the size of the crystal units, then the units are assembled on each detector crystal module in a bonding mode, and finally a plurality of rows of detectors are spliced, so that the processing difficulty is reduced compared with the whole processing of the anti-scattering grid of the whole detector module, and the alignment precision of the anti-scattering grid and pixels is improved. However, the problem is that the alignment angle of the anti-scatter grid of the plurality of crystals in the detector module and the X-rays may exhibit inconsistency due to the accuracy deviation of the assembly angle, and a series of image problems such as increased scatter, lost dose efficiency, and impaired spatial resolution may occur for the anti-scatter grid that deviates significantly from the design value. It is therefore important to ensure that the inclination angle of the anti-scatter-grid of each crystal unit is as close as possible to the design value. Disclosure of Invention The invention mainly aims to provide a tilt angle adjustable CT detector module and a tilt angle adjusting method, which are used for solving the problem that the alignment angles of anti-scattering grids of a plurality of crystal units and X rays in a multi-row CT detector module in the related art are inconsistent due to the accuracy deviation of assembly angles. In order to achieve the above object, the present invention provides an adjustable tilt angle CT detector module, comprising: A crystal unit; the crystal unit mounting bracket is provided with a plurality of crystal unit mounting positions, and the mounting surface of at least part of the crystal unit mounting positions is provided with an inclination angle; the adjusting piece is arranged at each crystal unit installation position, two adjusting pieces are arranged in the first direction and the second direction, the adjusting piece is used for adjusting the inclination angles of the crystal units in the first direction and the second direction, and the first direction and the second direction are horizontal and perpendicular to each other. Through the arrangement, on one hand, each crystal unit installation position is provided with an independent adjusting piece, so that the inclination angle of each crystal unit can be independently and bidirectionally adjusted, after the crystal units are installed on the crystal unit installation positions of the crystal unit installation support, the inclination angles of the crystal units in the first direction can be adjusted through the two adjusting pieces located in the first direction, and the inclination angles of the crystal units in the second direction can be adjusted through the two adjusting pieces located in the second direction, so that the inclination angles of the crystal units in the first direction and the second direction meet the requirements, the consistency of the anti-scattering grid of the crystal units and the alignment angle of X rays is ensured, all the crystal units can be ensured to uniformly and efficiently receive X-ray signals, signal deviation is reduced, the accuracy of original data is improved, and the finally reconstructed CT image is higher in resolution and clearer in detail. On the other hand, in the module assembly stage, need not to carry out high accuracy prepositioning to the crystal unit, the inclination is calibrated fast to the regulating part of accessible on-the-spot two directions, reduces the installation degree of difficulty, shortens the equipment cycle to if the crystal unit inclination skew in the use, need not to dismantle whole module, only can accomplish the calibration through the regulating part, reduces maintenance work load, reduction equipment downtime. Optionally, the adjusting piece includes accurate thin tooth adjusting bolt, and accurate thin tooth adjusting bolt and crystal un