2D Y Scan Mode

2D Y Scan Mode

The technique employed to scan the image is similar to that of the way a television screen works. The image is scanned from left to right (X) and bottom to top (Y). Because images are rasterized (consist of individual points or pixels) it is possible that what seems to be a smooth curve actually is broken up into line segments. As such there are times when during the scanning process there may be more then one pixel (point) on the y-axis at a given x-position. This software de-aliases this information in order to minimize the number of "matches" in the scan, specifically on the Y-axis. The default method is from bottom up since most plots will have most of their information at the bottom of the graph. This can reduce the scanning time considerably as you can see when you try the two different methods.

If the plot is cluttered, that is there are peaks very tight together or the spacing within a peak is so tight as to be essentially a single component, then the best method is top-down. This will guarantee that the peaks are captured which is often the most important part of the information.