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Updated: Aug 5, 2026
06:45
Automated Joint Space Detection Improves Bone Segmentation Accuracy
Published on: November 28, 2025
Robust ptychographic joint optimization via frequency marching and adaptive-confidence tuning
Optics Letters
|July 31, 2026
Summary
We developed J-FACT, a new method for ptychography that accurately reconstructs images and corrects scan geometry. This approach improves image quality even with significant calibration errors.
Area of Science:
- * Computational imaging and microscopy
- * X-ray science and technology
- * Image reconstruction algorithms
Background:
- * Ptychography enables high-resolution imaging but is sensitive to initial conditions and scan variability.
- * Simultaneous object, probe, and scan geometry recovery is challenging due to strong coupling and errors.
- * Existing methods struggle with significant miscalibration and scan inconsistencies.
Purpose of the Study:
- * To introduce J-FACT, a novel two-stage maximum a posteriori framework for robust ptychographic reconstruction and geometry self-calibration.
- * To enhance the accuracy and stability of ptychography under challenging conditions, including large geometry miscalibration.
- * To improve the fidelity of reconstructed images and diffraction consistency in ptychographic experiments.
Main Methods:
- * J-FACT employs a two-stage approach: Frequency Marching (FM) and Adaptive-Confidence Tuning (ACT).
- * FM expands the solution space by ensuring local consistency under large miscalibrations.
- * ACT refines the reconstruction at full resolution by adaptively regularizing geometry based on diffraction residuals.
Main Results:
- * J-FACT demonstrated improved reconstruction fidelity in both simulations and experimental data.
- * The method significantly enhanced diffraction consistency, even with substantial geometry miscalibration.
- * J-FACT proved robust against initialization, discretization, and scan-to-scan variability issues.
Conclusions:
- * J-FACT provides a robust solution for joint reconstruction and geometry self-calibration in ptychography.
- * The proposed framework effectively addresses the challenges of miscalibration and improves overall imaging performance.
- * J-FACT advances the practical application of ptychography in scientific research.
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01:09Functional Classification of Joints
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Synarthrosis
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Synarthrosis
An immobile...
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Linear systems are characterized by two main properties: superposition and homogeneity. Superposition allows the response to multiple inputs to be the sum of the responses to each individual input. Homogeneity ensures that scaling an input by a scalar results in the response being scaled by the same scalar.
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