Show Fft - JEOL JSPM-5200 Instructions Manual

６ ANALYSIS OPERATION

6.13.5 Show FFT

FFT processing is applied to the data of a displayed graph.
The related function is Remove DC Bias.
Select Show FFT from the Analyse pull-down menu. The names of the FFT
windows will be displayed in the pulldown sub-menu. The following FFT
windows are provided:
Select a desired FFT window. FFT is performed and the result is displayed.
6-108
FFT window
No window
Cosine window
Parzen window
Cosine arch
Hamming
The DC bias component is automatically eliminated before the FFT execution.
Description
FFT without window
W (n) = 0.5 − 0.5cos (10nπ/N)
W (n) = 1 − {n − 0.5 (N − 1)}2/0.5 (N+1)
W (n) = 1 − n − 0.5 (N − 1)/0.5 (N+1)
W (n) = 0.54+(1 − 0.54) cos (2πn/N)
TMPM5200-2