Article

Serial time-encoded amplified microscopy (STEAM) based on a stabilized picosecond supercontinuum source

Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong.
Optics Express (Impact Factor: 3.53). 08/2011; 19(17):15810-6. DOI: 10.1364/OE.19.015810
Source: PubMed

ABSTRACT Temporal stability of the broadband source, such as supercontinuum (SC), is the key enabling factor for realizing high performance ultrafast serial time-encoded amplified microscopy (STEAM). Owing to that the long-pulse SC (picosecond to nanosecond) generation generally results in an ultrabroadband spectrum with significant pulse-to-pulse fluctuation, only the ultrashort-pulse (femtosecond) SC sources, which offer better temporal stability, have been employed in STEAM so far. Here we report a simple approach to achieve active control of picosecond SC stability and to help extend the applicability of SC in STEAM from the femtosecond to the picosecond or even nanosecond regimes. We experimentally demonstrate stable single-shot STEAM imaging at a frame rate of 4.9 MHz using the CW-triggered picosecond SC source. Such CW-stabilized SC can greatly reduce the shot-to-shot fluctuation, and thus improves the STEAM image quality significantly.

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