See also psd controls.
Position sensitive detector data is a 2-D array. Instead of a single pencil detector a linear array of detectors is deployed, so for each incident angle you can simultaneously measure an array of reflected angles. Each Qz slice in the ICP file thus corresponds to a rocking curve. From this curve we can estimate the specular and background signal simultaneously.
The psd window shows four different graphs. The top left graph shows data from the entire PSD array as a false color plot. Below and beside this are graphs of slices through the array. On the bottom right is a graph of the specular, background and subtracted data derived from the array. The legend on the top right shows the colour values corresponding to the levels in the array.
There are two dashed vertical lines overlaying the array. The data between these lines is integrated to form the specular scan. An equal width region surrounding the specular region is integrated to form the background scan. These are subtracted to form the reduced data. Once the region is selected, you can use the attenuator window to scale the data as usual. The graph to the right shows the levels for each line.
By clicking the middle button in the array you can get a cross section through the data. The vertical slice shows the counts versus Qz and is shown on the graph to the right. The diagonal slice shows the counts for a constant Qz on the graph below.