Accelerated autofocusing of off-axis holograms using critical sampling.

Area of Science:

• Optics and Photonics
• Biomedical Imaging
• Digital Holography

Background:

• Accurate focusing is critical for high-resolution imaging in microscopy and multimodal imaging systems.
• Traditional autofocusing methods can be slow, limiting real-time applications.
• Off-axis holography offers rich information but requires efficient processing for autofocusing.

Purpose of the Study:

• To introduce a novel and rapid autofocusing (AF) approach for off-axis holography.
• To enhance the speed and efficiency of autofocusing in holographic imaging.
• To extend the autofocusing method for single-shot fluorescence imaging in multimodal systems.

Main Methods:

• A fast off-axis hologram autofocusing (AF) approach is proposed.
• The method utilizes redundant data elimination through critical resampling of the complex field.
• The technique is adapted for single-shot physical autofocusing in fluorescence imaging channels.

Main Results:

• The proposed methodology enables real-time autofocusing.
• Achieved up to 12x speed-up factors compared to classical autofocusing approaches.
• Successfully extended for single-shot physical autofocusing in multimodal imaging fluorescence channels.

Conclusions:

• The developed critical resampling method provides a significant speed enhancement for off-axis hologram autofocusing.
• This approach facilitates real-time autofocusing in complex imaging scenarios.
• The technique is valuable for improving the performance of multimodal imaging instruments.