An Automatic Calibration Method for the Field of View Aberration in a Risley-Prism-Based Image Sensor

Area of Science:

• Optics and Photonics
• Image Sensor Technology
• Computational Imaging

Background:

• Risley-prism-based image sensors offer expanded fields of view via beam control.
• Increased prism angles enhance field of view magnification but worsen imaging aberrations.
• Advanced aberration correction is crucial for these sensors.

Purpose of the Study:

• To develop an automated calibration method for Risley-prism image sensors.
• Enhance the speed, accuracy, and stability of aberration correction.
• Address the challenges posed by increased aberrations in wide-field imaging.

Main Methods:

• Utilized a two-axis turntable to acquire image datasets of a calibration plate at varying prism angles and object distances.
• Applied bicubic interpolation for pre-processing calibration plate images.
• Calculated and optimized calibration parameters for aberration correction.

Main Results:

• Verified the feasibility of the automated calibration method through experimental results.
• Achieved a reprojection error within 0.26 pixels at a distance of 3.6 m.
• Demonstrated effective aberration correction with the proposed method.

Conclusions:

• The automated calibration method is effective for Risley-prism image sensors.
• The system achieves high accuracy and stability in aberration correction.
• This approach enables reliable wide-field imaging with minimized aberrations.