光聲影像系統同時結合了光學影像與超聲波影像系統的優點，具有光學的高對比、高解析度，藉由樣品對雷射波長的選擇性吸收，再透過超收波探頭接收對軟組織有高穿透性的超聲波訊號。
本研究使用波長為1064 nm的Q-switch脈衝雷射來激發超聲波訊號，在訊號處理中，單一位置的光聲波訊號在數學演算法的計算後可以取得兩個重要的樣品參數，光聲訊號初始位置和最大聲壓值，分別表示著此單一位置與偵測探頭的距離和樣品物理特性。藉由控制步進馬達(電動平移台)讓樣品在二維空間中掃描可以重建樣品表面在空間中的幾何結構與材料特性。本團隊也嘗試了不同的樣品，來驗證本系統的可信度，最後為了模擬生物組織的樣品，製作了許多複合式的材料，也成功地還原出樣品表面的三維光聲影像。

Photoacoustic imaging system has both advantages of optical imaging system and ultrasonic imaging system. Using material’s absorption of certain wavelength, then reconstruct image by the photoacoustic signal received through low scattering acoustic wave, with high resolution of optical image systems and low scattering of ultrasonic image system.
In this study, a 2D translation stage scanning photoacoustic image system is built. The photoacoustic wave is excited by Q-switch pulse laser with 1064 nm wavelength. In each scanning position, two important parameters, signal starting position and maximum amplitude of acoustic pressure, will be calculated from photoacoustic signal. With 2D scanning of sample, the spacial distribution of sample’s surface and material information can be reconstruct.

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