Fluorescence lifetime imaging via spatio-temporal speckle patterns in a single-pixel camera configuration.

Area of Science:

• Spectroscopy
• Materials Science
• Imaging Technology

Background:

• Photoluminescence (PL) spectroscopy is effective for nanosecond decay mapping.
• Microsecond timescale emission dynamics mapping is currently time-consuming.

Purpose of the Study:

• To develop a faster, simpler method for fluorescence lifetime imaging (FLIM) on the microsecond timescale.
• To enable efficient mapping of photoluminescence decay dynamics.

Main Methods:

• Combined random temporal speckles excitation (RATS) with a single-pixel camera based on spatial speckles.
• Utilized a spatio-temporal speckle pattern for excitation and detection.
• Acquired data for microsecond PL decay mapping within minutes.

Main Results:

• Demonstrated proof-of-principle measurements on two samples.
• Reconstructed decays were compared to non-imaging measurements.
• Analyzed the impact of preprocessing on reconstruction noise.

Conclusions:

• The new FLIM method offers unmatched simplicity for mapping PL dynamics.
• The technique is suitable for monitoring charge carrier dynamics in perovskites and long-lifetime solid-state luminophores.
• This approach significantly reduces the time required for microsecond timescale PL decay mapping.