We demonstrate a two-color reduced-Doppler probe for ion imaging that, in many applications, offers advantages over conventional 2+1 resonance-enhanced multiphoton ionization detection. Using counterpropagating beams of two different colors, one of which is broadband 266 nm, we achieve convenient and sensitive D atom detection without the need for Doppler scanning. We demonstrate the approach using 224 nm photodissociation of DBr. This method improves the sensitivity and signal-to-noise ratio and presents advantages and opportunities for use in the other systems.
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