Novel scanning method and novel scanning device of optical resolution photo-acoustic microscope

Abstract

The invention discloses a novel scanning method and a novel scanning device of an optical resolution photo-acoustic microscope, belonging to the technical field of photo-acoustic imaging. The device disclosed by the invention has the working process and working principle that after being collimated by using a single mold optical fiber coupling component, pulse laser emitted from a laser emitter is input into a two-dimensional scanning galvanometer system; the two-dimensional scanning galvanometer system focuses the laser onto a target object to generate a photo-acoustic signal, and a linear area corresponding to a focusing area of a linear focusing ultrasonic detector is scanned; photo-acoustic signals generated in different scanning positions are transmitted to the linear focusing ultrasonic detector through a water tank full of an ultrasonic coupling liquid, and are converted into piezoelectric signals; after being amplified by using an amplifier, the piezoelectric signals are acquired by using a data acquisition card, and are stored in a computer for data processing. The optical resolution photo-acoustic microscope and the target object do not need to move relative to each other, the requirements of the optical resolution photo-acoustic microscope on a signal to noise ratio can be met, and meanwhile, a large view field range and a high resolution can be met.

Description

technical field [0001] The invention belongs to the technical field of photoacoustic imaging, and in particular relates to a novel scanning method and device for optical resolution photoacoustic microscopy. Background technique [0002] At present, when applying optical resolution photoacoustic microscope to image the target object at home and abroad, the most commonly used scanning method is to use the confocal method of point-focused ultrasonic detector and pulsed laser to excite and detect the photoacoustic signal, while using mechanical scanning photoacoustic microscope or the target object to obtain the image of the target object point by point. This scanning method has high requirements on the mechanical scanning motor, and the imaging speed is slow and expensive. In addition, the acceleration and deceleration process of the motor during mechanical scanning and the movement Any vibration will displace the image and affect the image quality. In response to the above pr...

AI Technical Summary

Problems solved by technology

[0002] At present, when applying optical resolution photoacoustic microscope to image the target object at home and abroad, the most commonly used scanning method is to use the confocal method of point-focused ultrasonic detector and pulsed laser to excite and detect the photoacoustic signal, while using mechanical scanning photoacoustic microscope or the target object to obtain the image of the target object point by point. This scanning method has high requirements on the mechanical scanning motor, and the imaging speed is slow and expensive. In addition, the acceleration and deceleration process of the motor during mechanical scanning and the movement Any vibration will displace the image and affect the image quality

In response to the above problems, many research groups at home and abroad have proposed many solutions, such as the use of high-performance voice coil motors, and the combination of optical scanning and mechanical scanning. These methods have indeed improved the imaging speed and solved the misalignment problem. , but it is difficult to miniaturize, and there is still relative motion between the photoacoustic microscope and the target object, which is inconvenient for some clinical applications

There are two other solutions that use a micro-scanning electron microscope to simultaneously scan the focused laser beam and the sound field, and use a two-dimensional scanning galvanometer system and an unfocused ultrasonic detector to image the target object. These two methods are used in photoacoustic microscopy and There is no relative motion between the target objects, but the effective field of view of the former is very small and the micro-scanning electron microscope is very fragile, and the signal-to-noise ratio of the detected photoacoustic signal is low due to the use of unfocused ultrasonic detectors in the latter, The quality of the collected photoacoustic microscopy images is poor, and the above problems limit the application of optical resolution photoacoustic microscopy

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