delay in data acquisition

[Chauhan]

HI All
I have a problem acquiring data using DAQ board. What we are doing is, we are moving a laser beam in a plane to scan a round sample which generates some voltage signal which is measured using a DAQ board. For doing so we move laser lets say along x-axis and measure the produced signal. Then we move laser along  y-axis in small amount and again move along x-axis in bacward direction. Thus doing so we are scanning a plane having a round sample. What we suppose at the end is an output with round shape since signal is generated inside the sample only. But actually when we move along positive direction of x , we have the signal . But when we come back along negative direction the signal starts to appear in the DAQ board after travelling a long distance after crossing the boundry of the sample. I am attaching the file  which is used to collect data and this file is placed in a for loop of main programme which moves the laser in farward and backward direction to scan the plane containg sample. I want to know if this delay in the data acquisition can be because of the time clock i have used in for loop of the data acquisition programme or because of any other reason. Your help isreally appreciated. Thanks to you all in advance.
Chauhan

[Matt_A]

Hello Chauhan,

It appears that this question is being addressed on another message board here. Please refer to that post for more information.