Contrast, spatial frequency, presentation time, moving velocity and phase reversal frequency of each grating are controlled independently.
每组光栅的对比度、空间频率、显示时间，移动速度和反相频率能单独控制。
2
Portal velocity and portal flow with phase contrast (PC) were measured.
相位对比法(PC)测门静脉血流速度、每分钟流量。
3
Results it was found that nerve conduction velocity, regenerated myelinated nerve fiber cross section area and number of nerve fiber were superior to those of the contrast.