【摘要】 为满足光声显微成像的信噪比、分辨率、成像深度等要求,使用高速大功率场效应管作为开关,以激光二极管代替典型光声显微成像常用的脉冲光参量振荡器(OPO)和染料激光器(dye laser),设计了一种低成本、结构紧凑的纳秒级激光脉冲驱动器;介绍了驱动器的电路结构,并进行仿真测试。结果表明:所得驱动电路同时适用于连续和脉冲激光二极管;过驱动激光二极管可以产生的电流重复频率50 kHz,最小脉宽约6 ns,峰值电流约50 A,单脉冲能量约200 nJ;激光脉冲的重复频率、脉冲宽度和脉冲能量均可以满足生物组织血红蛋白的显微成像要求,提高了成像速度,降低了激光器的使用复杂度,驱动器整体结构更加紧凑,同时大幅降低了光声显微成像成本。更多还原

【Abstract】 In order to meet the requirements of signal-to-noise ratio, resolution, imaging depth of photoacoustic microscopy, a low-cost, compact nanosecond laser pulse driver was designed. The high-speed and high-power FETs were used as switches, and the laser diodes were used to replace the pulsed optical parametric oscillators(OPO) and dye lasers commonly used in typical photoacoustic microscopy. The structure of the driving circuit was introduced and simulated and tested. The results showed that the driving circuit was suitable for both continuous and pulsed lasers diode. The overdriven laser diode can generate a current with repetition frequency of 50 kHz, a minimum pulse width of about 6 ns, a peak current of about 50 A, and a single pulse energy of about 200 nJ. The repetition frequency, pulse width and pulse energy of the laser pulse can meet the hemoglobin microscopic imaging requirements of biological tissues. The imaging speed was improved, the use complexity of the laser was reduced, the overall structure of the driver was more compact, and the cost of photoacoustic microscopy was greatly reduced.更多还原