Researchers at the Tokyo University of Agriculture and Technology have developed a smartphone-based digital holographic microscope capable of capturing and displaying three-dimensional (3D) holograms in near real-time. This portable and cost-effective device has the potential to revolutionize medical diagnostics and science education, particularly in resource-limited settings.

Traditional digital holographic microscopes require complex optical systems and powerful computers, limiting their portability and accessibility. To address these challenges, the research team, led by Yuki Nagahama, designed a simplified optical system fabricated using a 3D printer and integrated it with a smartphone-based computational platform. This integration allows the microscope to perform 3D measurements efficiently and affordably.

"Our digital holographic microscope uses a simple optical system created with a 3D printer and a calculation system based on a smartphone," said Nagahama. "This makes it inexpensive, portable, and useful for a variety of applications and settings."

A key innovation in this development is the use of band-limited double-step Fresnel diffraction for hologram reconstruction. This method reduces the number of data points required, enabling faster computational image reconstruction directly on the smartphone. As a result, the system achieves frame rates of up to 1.92 frames per second, facilitating near real-time observation of stationary objects.

The portability and affordability of this smartphone-based microscope have significant implications across various fields:

• Medical Diagnostics: In resource-limited settings, the device could be instrumental in diagnosing conditions such as sickle cell disease. Its ease of use and rapid 3D imaging capabilities make it suitable for point-of-care diagnostics, potentially improving healthcare outcomes in underserved regions.

• Education: The microscope offers students the opportunity to observe living organisms in 3D, both in classrooms and at home. This hands-on experience can enhance understanding of biological structures and processes, making science education more interactive and engaging.

• Field Research: For researchers conducting studies in remote locations, the device provides a lightweight and efficient tool for on-site analysis, eliminating the need to transport samples to well-equipped laboratories.

The research team validated the microscope's performance by imaging test objects with known patterns, successfully reconstructing accurate 3D images. They also demonstrated its capability by capturing cross-sectional images of biological samples, such as a pine needle.

Looking ahead, the researchers plan to enhance image quality by incorporating deep learning techniques. Digital holographic microscopes often produce unintended secondary images during hologram reconstruction. By leveraging deep learning, the team aims to suppress these artifacts, resulting in clearer and more reliable images.

This development marks a significant step toward making advanced scientific tools more accessible, with the potential to impact education, healthcare, and research globally.