Quote:
Originally Posted by merlinmaxwell
It was a domestic chip, what happened to it I have no idea.
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Philips had developed the chip for their domestic offering, the output of the chip was masked to serially provide RGB, RGB, RGB etc. When they came to develop their range of professional cameras they decided rather obviously the horizontal resolution of the chip was not sufficient, but, if they did away with the RGB masking the chip would then output a single stream of samples that was (just) about good enough for professional use.
So, they did away with the RGB masking and glued 3 of the chips to the back of a conventional light splitting prism and hey presto it was the heart of their professional range - the LDK 90. They also introduced the rotating mechanical shutter in front the prism block so that samples could be shuffled down vertically from the active (exposed) part of the sensor to the blanked off part of the sensor chip during the blanking interval therefore guaranteeing no overloading of vertically aligned individual pixel sensors if the camera happened to be looking a a very bright source.
The rotating shutter feature was stunningly effective. I went on the maintenance course for the camera in Breda. The lecturer pointed the camera at a 1KW tungsten lamp and zoomed in and focussed on the filament!! I'd never seen anything like it before or since. I think the light splitting prism was bought in from Sony or similar, it was certainly Japanese and not Philips own product. We did speculate to ourselves how reliable the rotating shutter would be.
We were told that in the event of 'no camera output' we should put our ears to the side of the camera to ensure the shutter was still rotating (it gave out a low level sort of 'ticking' sound) because if the shutter had stopped for some reason in the light path due to a fault it could of course block any light from reaching the sensors and hence apparently no output apart from syncs etc!
In practice the cameras were incredibly reliable, we had 5 and in all the years of operation (about 5) we only had one fault on one camera which I tracked down to a simple dry joint. In the end the cameras were replaced with their later counterparts - the LDK91 which was 16:9 capable.
I would put the cameras at the very low end of broadcast standard, if you looked very closely at the pictures you could see they weren't quite up to mustard.