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When colour TV started in the US in the 1950s (ignoring the short-lived CBS sequential system) the options for cameras were severely limited. The only candidates were image orthicons and vidicons.
IO tubes were bulky but ultimately they worked well enough. The cameras were huge. Marconi made an experimental camera in the UK, nicknamed the "coffin camera" on account of its size.
Vidicons were compact but the inherent laggy response made televising moving objects impossible. You could never match the 3 tubes so you got very nasty effects. This could be minimised with lots of light, hence their use in telecine. Though in Europe with 25Hz systems we usually used flying spot and speeded up the film by 4%.
As Adlershof has said, Philips developed the Plumbicon in the 1960s. It was available in time for the first European colour services in the UK and Germany. The Plumbicon was a much imroved vidicon with lead oxide target. Hence the name. I think the first Plumbicon camera was the Philips PC60, a 3 tube design. In Europe this was rapidly followed by the Marconi Mk VII and then the EMI 2001. Both were 4 tube designs. They reckoned the extra complexity was worth the improvement in registration and grey scale. The Y channel was full bandwidth, the RGB channels could be reduced BW. I think this also improved sensitivity and reduced noise.
Later cameras basically took high frequency luminance from the green channel. That's a simplified description, but it gave the advantages of 4 tube cameras with the simplicity of 3 tube.
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