雙光束型雷射都卜勒之動物血液流速 測定研究

Measurement of animal blood velocity using Dual-Beam mode of laser Doppler method

陳郭良(Guo-Liang Chen)

指導教授 ： 陳建銘

國立臺北科技大學/機電學院/光電工程系所/碩士(2005年)

摘要

本研究主要建構双光束型雷射都卜勒流速計於光學桌上，在此系統架構中，偵測待測粒子散射光之光偵測器原來架設在與光源異側，而本研究將光偵測器架設在與光源同側，以利將來應用在量測人體血液的流速。實驗中利用雞血作為待測流體，當稀釋血液中紅血球作為流體粒子時，大小距離合適，因而可量測並推算其血液流速。最後將已建立的光學系統設計成光纖光源模組，建立發展小型模組化光路設計之基礎。
實驗過程探討改變傳送血液之管的管徑與種類、血液流動的溫度、雷射入射於血液之角度及稀釋血液濃度等因素，以求得此流速計合適量測血液流速之條件。實驗結果顯示雷射光交會角度為主要影響量測結果之因素，隨著交會角度的改變，流體粒子通過雷射光束干涉區域所產生的散射光強度也相對改變，而影響了血液流速的正確性。應用這些條件做為光纖光源模組的量測基礎，在於血液流速的量測上，比較傳統氦氖雷射光源所得到的實驗結果，以了解如何設計小型模組化雷射都卜勒血液流速計與適合人體量測之血管條件。

關鍵字

雙光束型 ； 雷射都卜勒流速計 ； 血液流速 ； 模組化

並列摘要

In the study, we built a Dual Beam Mode of the frame on an optical table. By the optical system structure, the light of particle scattering is detecting by the photodetector which is set at the same side with the light source. The photodetector, which collect the scattering light of blood cell may measure the blood velocity according to Doppler frequency. The micro particles of dextran were used to characterize the LDA system first. And then, we measured the velocity of dilute chicken blood due to the size and distance of red blood cells is suitable.
In the experiments, we evaluate the relationship among the blood cell velocity and beams cross angle, diameter of glass tube, temperature variation of blood, and concentration of blood, etc. By analyzing the results of these experiments, we can know the main factor, that affect the precision of velocity measurement is the cross angle of two injected laser beams. If the cross angle is changed, the scattered intensity, which laser focus on fluid particles to make is changed relatively.
Finally, we designed the new module of optical system instead of the LDA on optical table, which is comprised by laser diode and optical fibers. By utilizing the measurement of chicken blood in previous setting, we also successfully measure the velocity of chicken blood with the infrared module in limited error. We compared the results of the module and LDA on optical table with Hi-Ne laser. They showed the much efficacy of blood velocity measurement by the new module, and the two beams laser methods will be possible to apply to measure the blood velocity of human someday.

並列關鍵字

Laser Doppler Aanemometry (LDA) ； blood cell velocity ； module

參考文獻

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