Near-infrared to visible upconversion imaging using a broadband pump laser

Area of Science:

• Optics and Photonics
• Biomedical Imaging
• Materials Science

Background:

• Upconversion imaging offers a pathway for visualizing near-infrared (NIR) signals in the visible spectrum.
• Traditional upconversion methods often face limitations in spatial resolution and the number of detectable elements.

Purpose of the Study:

• To develop and demonstrate an improved upconversion imaging technique.
• To enhance the number of resolved spatial elements and overall performance compared to narrowband excitation.

Main Methods:

• Utilized a dedicated broadband pump laser for excitation.
• Performed upconversion imaging experiments converting NIR to visible light.
• Quantified spatial elements, field of view, resolution, and conversion efficiency.

Main Results:

• Achieved up to 56x64 spatial elements with a 2.7 nm pump spectrum.
• Demonstrated over a 10-fold increase in resolved elements compared to narrowband lasers.
• Experimental results aligned well with theoretical simulations.
• Computed sensitivity was found to be competitive with direct InGaAs camera detection.

Conclusions:

• Broadband excitation significantly enhances the performance of upconversion imaging.
• The developed method offers a promising alternative for sensitive NIR imaging applications.
• The technique shows potential for applications requiring high spatial resolution and sensitivity.