eli5 Direct streaming pre CCD and CMOS


Hi everybody, maybe a stupid question, how did television broadcasters streamed video in the first tv period before the development of all the electronics we are using today like CCD anc CMOS sensors? Thanks

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Before digital technology you had a piece of kit that sort of worked like a CRT in reverse- the subject image is projected onto a small screen that becomes electrically charged where light hits it, then an electron gun rapidly sweeps a beam across the screen. The interference between the electrons and the charged parts of the screen is interpreted as the image signal, and after any secondary processing that can be broadcast from TV antennas.

Television cameras used a gadget called a [vidicon tube](https://en.wikipedia.org/wiki/Video_camera_tube ), where a scanning electron beam sampled a surface where lenses formed an image of the scene. Vacuum tubes can be used to do many almost magical things, they don’t get the credit they deserve in today’s digital era.