Fig. 2.

Characterization of the SRS imaging flow cytometer with polymer beads. (A) Four-color SRS images of PS, PMMA, and PE beads. The Raman shifts used are 2,860 cm⁻¹ (λ₁), 2,910 cm⁻¹ (λ₂), 2,937 cm⁻¹ (λ₃), and 3,040 cm⁻¹ (λ₄). (B) Four-color SRS spectra in comparison with the spectra between 2,800 and 3,100 cm⁻¹ obtained by conventional SRS microscopy. (C) Linearly decomposed images of PS, PMMA, and PE beads shown in red, green, and blue, respectively. (D) SRS image library of polymer beads in a mixture flowing at a speed of 2 cm/s. The pixel dwell time for the 4-color SRS images is 210 ns.