Multi-Unit CT Imaging Layout for Higher Angular Resolution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing computed tomography (CT) apparatuses face limitations in increasing angular resolution without increasing the frame rate of the radiation detector or reducing the rotation speed of the imaging unit, leading to potential image quality deterioration due to subject movement and prolonged imaging times.
Innovation Solution
A CT apparatus with multiple imaging units, each comprising a radiation source and detector, is designed to rotate around the subject's body axis, with differing phases and positions to achieve higher angular resolution by adjusting emission and acquisition times, and correcting for manufacturing errors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the frame rate of the radiation detector is increased to improve angular resolution, then the angular resolution is improved, but the device complexity and cost increase
Solution Approach 1:
The imaging system is divided into multiple imaging units (first imaging unit, second imaging unit, etc.), each with its own radiation source and detector. These units are disposed at different angular positions around the subject. By segmenting the imaging function across multiple units with different phases, the system achieves higher effective angular resolution without requiring a single detector to operate at excessively high frame rates.
2Measurement precision
If the rotation speed of the imaging unit is reduced to improve angular resolution, then the angular resolution is improved, but the imaging time increases and subject burden increases
Solution Approach 1:
Multiple imaging units operate in periodic cycles with different phases. Each imaging unit acquires projection images at its own timing within the rotation cycle. The processor coordinates these periodic acquisitions from multiple units to reconstruct the complete set of projection images. This periodic multi-unit operation achieves high angular resolution while maintaining a reasonable rotation speed and total imaging time.
3Measurement precision
If multiple imaging units with different phases are used to improve angular resolution, then the angular resolution is improved, but the device complexity increases
Solution Approach 1:
Each imaging unit is designed with universal functionality to emit radiation and detect transmitted radiation. The radiation sources and detectors are configured to perform the same basic imaging function, but at different angular positions and phases. This universality allows the system to achieve higher angular resolution through spatial distribution rather than requiring fundamentally different or more complex components in each unit.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances angular resolution without increasing the frame rate or reducing rotation speed, thereby reducing subject burden and image quality issues.
Implementation Method 1
a radiation source that emits radiation having a quadrangular pyramid shape to a subject and a radiation detector in which a plurality of pixels detecting the radiation transmitted through the subject
Data Source
AI summary
A CT apparatus includes a plurality of imaging units, a rotation mechanism, and a CPU. The imaging unit includes a radiation source and a radiation detector. The rotation mechanism rotates the plurality of imaging units around a body axis of the subject while maintaining a disposition interval. An imaging control unit of the CPU controls operations of the plurality of imaging units and the rotation mechanism. An angular interval that is determined by a frame rate of the radiation detector and a rotation speed of the imaging unit and that defines an acquisition time of a projection image based on the radiation is the same for the plurality of imaging units. The plurality of imaging units have different phases in a rotation direction, and positions where the plurality of imaging units acquire the projection images are separated by a set angle that is less than the angular interval.