CRT displays [was: computer graphics in the 1950s]

Christian Corti cc at
Fri Oct 24 04:17:05 CDT 2008

On Thu, 23 Oct 2008, Tony Duell wrote:
>> without deflection plates is rather difficult to use as a
>> vector display, but that's a matter of complicated and unconventional
> One without _any_ deflection system is hard to use as either a vector or
> raster display :-)

I just want to mention that there were polar-coordinate tubes. They may be 
either completely electrostatic or mixed static/magnetic. I've just read 
an interesting discussion on the 3DP1 on the net.

> I have several vector displays here. The ones that were designed by
> companies known for making CRT-based instruments like 'scopes -- HP and
> Tektronix -- use large-screen electrostatic CRTs. But the DEC VR14 and
> the Vectrex video game both use electromagnet CRTs.

The DEC VR14/VR17 are electromagnetic CRTs. The two push-pull power 
amplifiers for both ordinates as well as the current through the 
deflection coils are quite impressive.


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