An electron gun produces a beam that contains only electrons; there is no conductor, and I think holes can exist only in the presence of a conductor. So you can't shoot a beam of holes through a vacuum. But if the material between the gun and the screen were a semiconductor, maybe you could draw pictures on the screen using a beam of holes? I mean, I don't see why a beam of holes can't be focused just like a beam of electrons.
> I mean, I don't see why a beam of holes can't be focused just like a beam of electrons.
Wouldn't electrons rush in to fill the holes from every direction, rather than just the intended one? That's what my intuition says anyway. So yeah, my guess would be that it is in fact not possible.
That blade cuts both ways; the electron beam in a CRT travels through a vacuum, there's nothing to "rush in". A hole beam would have to travel through a medium with no free electrons.
An electron gun produces a beam that contains only electrons; there is no conductor, and I think holes can exist only in the presence of a conductor. So you can't shoot a beam of holes through a vacuum. But if the material between the gun and the screen were a semiconductor, maybe you could draw pictures on the screen using a beam of holes? I mean, I don't see why a beam of holes can't be focused just like a beam of electrons.