Coherent anti-Stokes Raman scattering is an extremely powerful non-linear optical (NLO) microscopy technique for label-free vibrational imaging allowing for chemical characterization of biological samples in their native state. We introduce here video-rate wide-field signal generation and acquisition over a large field of view (tens of micrometers) allowing for real-time investigation of fast biological dynamics. To this aim, our innovative approach employs an amplified femtosecond ytterbium laser source delivering high energy (≈ µJ) pulses in the near-infrared at 1035-nm central wavelength and 2-MHz repetition rate from which pump and Stokes beams are generated. Narrowband pump pulses with ≈1.1 nm bandwidth (10 cm−1) guarantee sufficient spectral resolution for the vibrational Lorentian peaks. Broadband Stokes pulses in the 1100-1500nm range are produced via supercontinuum generation in 10-mm YAG crystal and amplified in a non-collinear optical parametric amplifier (NOPA). This allows us to acquire hypercubes that cover the entire fingerprint region of the molecular vibrational spectrum, the richest in chemical information. Our results pave the way for future clinical diagnostics applications with video-rate imaging capabilities.
Video-rate wide-field broadband CARS microscopy
Ceconello, Chiara;Vernuccio, Federico;Bresci, Arianna;Manetti, Francesco;Sorrentino, Salvatore;Cerullo, Giulio;Polli, Dario
2023-01-01
Abstract
Coherent anti-Stokes Raman scattering is an extremely powerful non-linear optical (NLO) microscopy technique for label-free vibrational imaging allowing for chemical characterization of biological samples in their native state. We introduce here video-rate wide-field signal generation and acquisition over a large field of view (tens of micrometers) allowing for real-time investigation of fast biological dynamics. To this aim, our innovative approach employs an amplified femtosecond ytterbium laser source delivering high energy (≈ µJ) pulses in the near-infrared at 1035-nm central wavelength and 2-MHz repetition rate from which pump and Stokes beams are generated. Narrowband pump pulses with ≈1.1 nm bandwidth (10 cm−1) guarantee sufficient spectral resolution for the vibrational Lorentian peaks. Broadband Stokes pulses in the 1100-1500nm range are produced via supercontinuum generation in 10-mm YAG crystal and amplified in a non-collinear optical parametric amplifier (NOPA). This allows us to acquire hypercubes that cover the entire fingerprint region of the molecular vibrational spectrum, the richest in chemical information. Our results pave the way for future clinical diagnostics applications with video-rate imaging capabilities.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
