The invention provides a method for the observation, identification, and detection of blood cells, which comprises a label-free third harmonic generation (THG) tomography having a property of least injury. Submicron morphologies and granularities of blood cells can be revealed and reflected through this method. Leukocytes with different granularities can thus be identified from the intensity and distribution of THG signals generated within cells. Furthermore, the method of the present invention is capable of performing a noninvasive sectioning microscopy image in vivo. Without cell and tissue damage, label-free THG microscopy can real-time observe the morphology and dynamics of blood cells flowing in vessels or trafficking in tissues； Red blood cells and leukocytes have different morphology in blood flow and can thus be distinguished by in vivo third harmonic generation microscopy.本發明提供一種血球之觀察與鑑別偵測方法，該方法以低傷害性的三倍頻光學斷層掃描，無須染色步驟，即可觀察血球細胞的次微米型態細節與顆粒性，透過細胞內三倍頻訊號的強弱與分布情形，可以鑑別不同顆粒性的白血球。此外，本方法可以在活體中非侵入式的進行光學切片，在不破壞細胞與組織的狀態下，以不需染色的三倍頻影像，取得血管中或組織中的即時白血球型態，運用不同血球的流體動力影像差別，還可以分別血管中的紅血球和白血球。
