The dispersive mirrors I have clip the edges of the spectrum from my oscillator, does this matter?

To obtain the pulse duration measured during manufacture, the complete spectrum is needed. Also the outer low level wings do contribute considerably to getting the short pulse duration as specified. Thus, clipping the edges of the spectrum or using dispersive mirrors outside their specified range for the dispersive properties will result in degradation, and the pulse duration not being able to reach the value specified.

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