03-11-2019, 11:06 PM
Yes, you can have red, orange, yellow, yellowy green and green easily, though it's an illusion, as is Colour TV. I've done it with a 4MHz PIC. Maybe your Z80 just had too much other things to do as I had a multplexed LED panel driven by a Z80.
Aliens with tetrachromatic vision or even different trichromatic spectral responses would find ALL colour screen technology equally horrible. It's a trick which is why an RGB LED is no use for room lights. All LED lighting has to have phosphors to give any sort of useable colour rendition. Colour temperature only tells you how white it looks directly, or on a grey / white surface. Colour Rendition tells you how well everything else will reflect. Real cyan colours (i.e. things that absorb all other parts of the spectrum) tend to look dark, bluer or greener with most LED lights as most commonly they have the illusion of white by a broad spectrum yellow phosphor (that outputs reds and greens too) on a Blue / Violet / near UV LED. LEDs are inherently monochromatic.
The stick filament LEDs that are 55V or 115V per stick have a yellow phosphor coating. Better ones add some other colours of LED than the short wave blue. They give the best light of any LED, in omnidirectional and colour rendition. The phosphor is running cooler than the high power LEDs as are the LEDs. So longer live. No switch mode PSU either, so some are allegedly dimmable.
The bulb envelope is gas filled to aid cooling.
Sadly the tech is too bright for scale / dial lamps. They seem more natural than CFLs, no RFI even right beside it on LW or MW. Using a CD to see the spectrum there were no obvious holes. There is enough short wave light to recharge Zinc Sulphide luminous paint.
Aliens with tetrachromatic vision or even different trichromatic spectral responses would find ALL colour screen technology equally horrible. It's a trick which is why an RGB LED is no use for room lights. All LED lighting has to have phosphors to give any sort of useable colour rendition. Colour temperature only tells you how white it looks directly, or on a grey / white surface. Colour Rendition tells you how well everything else will reflect. Real cyan colours (i.e. things that absorb all other parts of the spectrum) tend to look dark, bluer or greener with most LED lights as most commonly they have the illusion of white by a broad spectrum yellow phosphor (that outputs reds and greens too) on a Blue / Violet / near UV LED. LEDs are inherently monochromatic.
The stick filament LEDs that are 55V or 115V per stick have a yellow phosphor coating. Better ones add some other colours of LED than the short wave blue. They give the best light of any LED, in omnidirectional and colour rendition. The phosphor is running cooler than the high power LEDs as are the LEDs. So longer live. No switch mode PSU either, so some are allegedly dimmable.
The bulb envelope is gas filled to aid cooling.
Sadly the tech is too bright for scale / dial lamps. They seem more natural than CFLs, no RFI even right beside it on LW or MW. Using a CD to see the spectrum there were no obvious holes. There is enough short wave light to recharge Zinc Sulphide luminous paint.
