Amorphous Silicon Photodiode Array for Radiotherapy Beam Characterization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional radiotherapy beam characterization systems suffer from low resolution and lack of real-time measurement capabilities, leading to inadequate precision and efficiency in adjusting beam characteristics for cancer treatment.
Innovation Solution
The implementation of a beam detection subsystem with a densely pixilated image detection array, such as an amorphous silicon photodiode array, which generates high-resolution data points for real-time characterization and feedback, enabling precise analysis and adjustment of radiotherapy beams.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional beam characterization systems use scintillation screens and mirrors with CCD cameras, then beam measurement is possible, but measurement resolution is limited and geometric distortion occurs
Solution Approach 1:
The detector is divided into multiple independent photodiode elements arranged in an array, with each element contributing to the overall measurement. This segmentation enables high-resolution beam characterization by combining signals from many discrete sensing points, achieving superior measurement precision without requiring complex optical components like mirrors and CCD cameras
Solution Approach 2:
The patent replaces the mechanical optical system (scintillation screens, mirrors, CCD cameras) with a direct semiconductor-based detection system using photodiodes. This substitution eliminates the multiple conversion steps (proton-light-mirror-charge) and associated geometric distortions, providing a more direct and accurate measurement approach
2Measurement precision
If ion chambers and ion chamber arrays are used for beam characterization, then beam measurement is possible, but measurement resolution is limited
Solution Approach 1:
The photodiode array is segmented into many small sensing elements, providing high spatial resolution for beam characterization. This segmentation allows precise mapping of beam intensity distributions while maintaining fast response times, overcoming the resolution limitation of conventional ion chamber arrays
Solution Approach 2:
The patent changes the detection parameter from slow-integrating ion chamber signals to fast-response photodiode signals. This parameter change enables both high measurement resolution and real-time productivity, allowing rapid beam characterization without the resolution compromises required by ion chamber systems
3Measurement precision
If wire chambers or film are used for beam characterization, then beam measurement is possible, but real-time measurement capability is lost
Solution Approach 1:
The patent replaces film-based or slow-response wire chamber systems with electronic photodiode detection. This substitution eliminates the time required for film development and enables immediate digital signal processing, achieving real-time beam characterization while maintaining measurement precision
Solution Approach 2:
The photodiode array system provides self-service by generating electrical signals directly from incident protons without requiring external processing steps like film development. The system automatically converts proton energy deposits into measurable electrical signals that can be immediately analyzed, eliminating time losses associated with conventional film or wire chamber methods
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 provides high-resolution, real-time characterization of radiotherapy beams, allowing for accurate adjustment of beam parameters like flatness, symmetry, and uniformity, ensuring effective delivery of radiation doses to target volumes.
Implementation Method 1
an image detection array (e.g., an amorphous silicon photodiode array, an organic semiconductor photodiode array, etc.) with a densely pixilated surface that enables the acquisition of a high number of beam data points
Data Source
AI summary
A method for determining parameters of a beam. As a part of the disclosed method, a beam is received at an image detection array where charges are generated and collected, at a plurality of pixels. Values associated with at least one of a plurality of parameters of the beam are determined by integrating information supplied from each of the pixels. Feedback is generated that presents the values.