Light from the laser goes through the optical circulator, and is divided into the sample and referencearm by the fiber coupler.
激光器发出的光通过光环行器，被光纤耦合器分成样品臂和参考臂。
2
Time Domain OCT (TDOCT) gets the image of inner sample's structure by axial scanning in referencearm which limits imaging speed.
时域oct系统为了得到被测样品的断层图像，需要分别进行横向和纵向扫描，限制了成像速度。
3
The heterodyne detection is used to detect the output signal frequency difference between the referencearm and sensing arm, which is caused by the temperature variation.