Dome tweeter under near field scanner

Hello people,

I'm just confused to know how's ugly expensive dome tweeter reeact to signal.
I made a test of on of known model 1" textil dome tweeter (I can't show manufacturr name), by Klippel Near Fieeld Scanner NFS). Se the picture please.
Indeed all of domes move like this?!
I made a video about that., but Russian language, you can use subtitls if you interested in.


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I suppose this is a soft-dome (coated cloth): pretty much as could be expected from a lossy diaphragm. But is it a problem? Not really since the non-conform acting parts of the dome have minimal impact on the the total on axis amplitude because of the minimal excursion those parts of the dome tend to make. But yes, they have impact off axis: hence the dips 'n peaks off axis we are all used to see in spec sheets and measurements.
But why can't you reveal the brand and type of this dome tweeter?
No, I think this a fatal problem. Not only does the area of the diaphragm that forms the sound field turn out to be smaller, but also the radiation of the “lagging” parts of the diaphragm is mixed in the chaotic phase. Including along the axis.
I cannot say the name of the manufacturer, this commercial information does not belong to me.
There is no such thing as commercial information in publishing measurement results of any sort or type. Fatal is a bit bit heavy handed methinks.....
Furthermore, any type of real life diaphragm will sooner or later break up and show somewhat chaotic behaviour: even larger ribbons have their isssues.