[Proposal and verification of presampled MTF measurement by simple analysis using the edge method]

Area of Science:

• Medical Imaging
• Radiography
• Image Quality Assessment

Background:

• The International Electrotechnical Commission (IEC) edge method for presampled modulation transfer function (presampled MTF) measurement offers simpler image acquisition than the slit method.
• However, the edge method struggles with accuracy due to noise amplification from differentiation.

Purpose of the Study:

• To develop an effective method for accurate presampled MTF measurement using the edge method.
• To investigate factors influencing measurement accuracy in edge profile analysis.

Main Methods:

• A novel approach synthesizing multiple edge profiles and binning them at regular intervals was proposed.
• The influence of bin width (10-20% of sampling interval) and edge inclination angle error (up to 0.05 degrees) on accuracy was analyzed.
• Measurement conditions, including an allowed angle range of 1-5 degrees, were established for accurate results up to the Nyquist frequency (fn).

Main Results:

• The proposed synthesis and binning method effectively reduces noise amplification issues inherent in the edge method.
• Optimal parameters for bin width and edge inclination angle were identified to ensure measurement accuracy.
• Accurate presampled MTF measurements up to the Nyquist frequency were achieved under the specified conditions.

Conclusions:

• The refined edge method provides a viable and accurate alternative for presampled MTF measurement in computed radiography (CR) systems.
• The study validates the proposed method by showing good agreement with traditional slit method measurements on a CR system.