Resolution analysis programs

These 2 Aladdin programs make QA a little easier by automatically measuring FWHM of any line or slit source image.

The files input must be 1024x1024 pixels, and it is up to you to pick the correct program for your file.

If the lines are parallel with the Y axis use resy.

If parallel with the X axis use resx

The programs as they are currently set measure FWHM in  approximately 100 positions (using the NEMA slit phantom) and return the average and the maximum values.

The peaks are found automatically, so you can use pretty well any line spread phantom, and the next line of measurements is decided by the spacing parameter.

The spacing between lines of measurements is currently set to 128 pixels but you can see in the script it is very easy to change this.

So where do you get the line object from? Well you can use virtually any. Maybe the Veenstra DLP phantom, or you can just use a single line such as a capillary. For intrinsic measurements you could use a NEMA specification slit phantom. I bought one of these from Bartec Technologies.  Below is a raw image of

the test object and output from the program resy.

The image can be downloaded in Dicom format (HERE) so you can use it to trial the program.

The program is written without calling the curve fitting routines, the FWHM is simply that returned as a curve property. However the value returned in pixels is not integer, so I presume it is calculated by interpolation between the points surrounding the half maxima.

Here are the Aladdin programs: