Edge extraction using a time-varying vortex beam in incoherent digital holography

Area of Science:

• Optics and Photonics
• Holography
• Image Processing

Background:

• Optical Scanning Holography (OSH) is a technique for holographic recording.
• Incoherent imaging systems often face challenges with contrast and resolution.
• Vortex beams offer unique properties for optical manipulation.

Purpose of the Study:

• To demonstrate edge extraction using a time-varying vortex beam (TV-VB) in incoherent optical scanning holography (OSH).
• To investigate the effect of spiral phase plate (SPP) position on edge reconstruction quality.
• To validate the proposed method through experimental comparison with simulations.

Main Methods:

• Utilizing a two-pupil heterodyne scanning optical system in OSH.
• Implementing a delta function as one pupil and a spiral phase plate (SPP) as the other to generate a TV-VB.
• Scanning the TV-VB over an object to holographically record edge-only information.
• Experimentally translating the SPP away from the pupil plane to optimize edge contrast.

Main Results:

• Successful holographic edge extraction using the TV-VB in incoherent OSH.
• Achieved improved edge contrast by adjusting the SPP position.
• Experimental results showed strong agreement with computer simulations.

Conclusions:

• The proposed TV-VB method effectively extracts edges in incoherent OSH.
• Translating the SPP is a viable technique for enhancing reconstructed edge contrast.
• This approach offers a promising method for edge-only information recording.