超聲透鏡與共振組合之快速體積多光子成像

Rapid Volumetric Multiphoton Imaging with the Combination of an Ultrasound Lens and a Resonant Mirror

許家偉(Chia-Wei Hsu)

指導教授 ： 陳顯禎

國立交通大學/光電學院/影像與生醫光電研究所/碩士(2018年)

摘要

雙光子點掃描顯微鏡基於掃描器的依序掃描來形成三維體積成像(volumetric imaging)，為了提高體積成像的速度，本論文藉由超聲透鏡提供快速的軸向掃描，共振鏡則是提供快速的側向掃描，將超聲透鏡與共振鏡的組合加入雙光子點掃描顯微鏡中，該顯微鏡通過FPGA快速精確地控制到以共振頻率8 kHz取得x-z平面的圖像，再使用震鏡對y方向的掃描完成快速的體積成像。95 MHz的飛秒雷射脈衝同步信號作為高效率收集激發的非線性光學信號，並且累積兩發脈衝的信號作為一個像素，同時，即時精確記錄焦點的位置資訊，因此，體積成像可以被重建於高達47.5 MHz的像素速率和位置資訊。在y方向256幀的情形下，體積成像速率可達到每秒30個體積影像(volumes per second)，且能夠量測15 Hz的動態，並應用於生物組織的成像。

關鍵字

多光子激發螢光顯微術 ； 可調變超聲梯度折射率透鏡 ； 共振掃描震鏡 ； 現場可程式化閘陣列

並列摘要

Two-photon point-scan microscopy requires sequential scanners to complete 3D volumetric imaging. To increase the speed of volumetric imaging, the ultrasound lens provides ultrafast axial scanning, and the resonant mirror provides fast lateral scanning. The combination of a tunable acoustic gradient (TAG) lens and a resonant mirror are integrated into a multiphoton excited (MPE) microscope that is rapidly and precisely controlled by an embedded field programmable gate array (FPGA) to acquire images at 8 kHz in the x-z plane. In addition, a galvanometer scan y direction to complete rapid volumetric imaging. Pulse train signal of femtosecond laser with 95 MHz repetition rate is adopted as the synchronous trigger for efficiently acquiring excited nonlinear optical signal. On average, two pulses laser contribute into one pixel. Simultaneously, the position information of focal points can be recorded precisely in real-time. Hence, rapid volumetric imaging can be reconstructed with up to 47.5 MHz pixel rate and position information. Rapid volumetric imaging rate can achieve 30 volumes per second according to 256 frames in y direction, measure 15 Hz dynamics, and apply to biological fluorescent image.

並列關鍵字

Multiphoton excited fluorescence microscopy ； tunable acoustic gradient index of refraction lens ； resonant mirror ； field-programmable gate array

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