SPECT Collimator Hole Orientation Measurement

The patent applies preliminary action by measuring and storing the actual collimator hole orientation angles (θx, θy) before the reconstruction process. A calibration procedure is performed offline to create a lookup table or vector map of the actual hole directions, which is then used during reconstruction. This pre-characterization of the collimator's actual geometry allows the reconstruction algorithm to compensate for manufacturing errors without adding complexity to the real-time reconstruction process.

The patent uses copying by creating a digital model or vector map that replicates the actual collimator hole orientations. Instead of physically measuring each hole during reconstruction, the system creates a computational copy of the collimator's actual geometry through offline calibration using line sources. This digital twin or lookup table is then referenced during reconstruction, avoiding the need for complex real-time measurement systems while achieving high measurement precision.

The patent applies preliminary action by performing the reference collimator calibration once during system setup or manufacturing, rather than repeatedly during each measurement process. The offset distances (dx, dy) between reference and measured collimator line images are determined in advance and stored. This pre-determined calibration data is then reused for subsequent measurements, achieving high measurement precision without repeating the time-consuming reference comparison process for every collimator inspection.