White light on-axis digital holographic microscopy based on spectral phase shifting

Area of Science:

• Optical microscopy
• Holography
• Digital imaging

Background:

• Traditional phase shifting digital holographic microscopy often relies on piezoelectric transducers (PZT).
• PZT-based systems can be susceptible to environmental vibrations, leading to speckle noise.
• Achieving full-color 3D imaging and speckle-free results simultaneously presents a challenge in microscopy.

Purpose of the Study:

• To describe and experimentally validate a white light on-axis digital holographic microscopy system.
• To demonstrate spectral phase shifting as a viable alternative to PZT-based phase shifting.
• To highlight the system's capabilities in producing speckle-free and full-color 3D spectral section images.

Main Methods:

• Development of an on-axis digital holographic microscopy setup utilizing white light.
• Implementation of a spectral phase shifting technique.
• Generation of a partial coherent source by combining a white light source and a spectral tunable filter.

Main Results:

• Experimental verification of spectral phase shifting as an effective phase shifting method in digital holographic microscopy.
• Demonstration of speckle-free imaging capabilities due to the use of a partial coherent source.
• Successful acquisition of full-color 3D spectral section images.

Conclusions:

• Spectral phase shifting digital holographic microscopy provides a robust alternative to PZT-based methods.
• The proposed system effectively mitigates speckle noise, enhancing image quality.
• The technique enables advanced 3D imaging with full-color spectral sectioning capabilities.