Environmental SEMs do not require vacuum and can be used for nonconductive samples. The beam ionizes the air which prevents the sample from charging. Magnification is limited but it is more than enough for this.
You can tell it is SEM and not optical by the depth of field. An optical image at this magnification would have much less DoF so the peaks/valleys would be blurry.
Environmental SEMs do not require vacuum and can be used for nonconductive samples. The beam ionizes the air which prevents the sample from charging. Magnification is limited but it is more than enough for this.
You can tell it is SEM and not optical by the depth of field. An optical image at this magnification would have much less DoF so the peaks/valleys would be blurry.
That’s very cool. I had not heard of ESEMs till you commented. I’ll have to look into them more.