Wide-field polygon-scanning photoacoustic microscopy of oxygen saturation at 1-MHz A-line rate

High-speed high-resolution laser diode-based photoacoustic microscopy for in vivo microvasculature imaging

“…Photoacoustic tomography is a hybrid imaging modality in which the detected ultrasonic signals are induced by the absorption of pulsed light [1]. Taking the advantage of intrinsic optical absorption contrast, photoacoustic microscopy (PAM) has been widely used to provide high-resolution and label-free images for functional, metabolic, and histological imaging [2][3][4][5][6][7][8]. However, the costly and bulky lasers, such as Q-switched diodepumped solid-state laser, Ti:sapphire laser, or optical parametric oscillator laser, are usually required to generate high-energy light pulses with a short pulse width for PA signal generation, preventing the wide usage of PAM system for clinical applications.…”

Ultra-widefield photoacoustic microscopy with a dual-channel slider-crank laser-scanning apparatus for in vivo biomedical study

“…Although the scanning time technically depends on the pulse repetition rate (PRR) of the laser and scanning mechanism, it is theoretically limited by the sound speed of the PA waves in biological tissues [ 23 ]. Several high-speed scanning techniques for OR-PAM have been reported, such as galvanometer scanner, microelectromechanical system (MEMS) scanner, hexagon-mirror scanner, and voice-coil scanning system [ 8 , [24] , [25] , [26] , [27] , [28] , [29] , [30] ]. These scanners can be classified into two main mechanisms including mechanical scanning (voice-coil scanner) and optical scanning (the other scanners).…”

“…Thus, these galvo-mirror-based optical scanning OR-PAMs have a relatively low SNR and/or a short scanning range within the spot size of the transducer. Therefore, the recent development of optical scanning system has employed a water-immersible mirror to simultaneously steer both focused the optical beams and emitted acoustic waves [ 8 , 26 , 28 ]. Although these OR-PAMs increase the B-scan rate up to ten of hundreds Hz with a relatively good SNR, the scanning range is still narrow.…”

Classification and discrimination of real and fake blood based on photoacoustic spectroscopy combined with particle swarm optimized wavelet neural networks

“…More importantly, the problems of scattering light and spectral overlap can be overcome because the method captures ultrasonic signals rather than photons, which can improve the detection accuracy. To date, photoacoustic spectroscopy has already been used in biomedical diagnosis, e.g., blood glucose [ [12] , [13] , [14] ], blood oxygen [ [15] , [16] , [17] ], and tumor detection [ 18 , 19 ]. However, research on the classification and discrimination of real or fake blood by using photoacoustic spectroscopy has not been reported before.…”