Directly-injected orange-yellow diode lasers soon?

[kecked]

There is also a color system called cmyk I believe that uses yellow as a primary color. It that is for printing so not for projection.

 

[paul1598419]

Yes, for inks and paint, yellow is a primary color, not green. They often use cyan, magenta, yellow and black for printing.

 

[Grn05gt]

There are benefits to having direct yellow for projectors and such, so i'd give it some chance at least.

Having yellow as a color can increase the efficiency of a display or projector quite a bit - for now it's mostly Sharp developing this for screens, but others could very well tag along.

It doesn't add that much to the gamut of a display system since our eyes aren't that impressed by monochromatic yellow as they are by monochromatic cyan, but you could achieve more brightness at lower cost if you had yellow in the mix.

I have a couple of PJ's as well as a few rgb/rgv modules. I have a sweet spot for yellow. Getting any of the RGB units configured for good yellow can be a task without messing up the rest of the color mix, specifically white!

I have 2 565nm's in hand and 2 575nm's on order.

My question is, and may be for the guys at PL more than here, but, how would be the best way to mix in yellow with an RGB module?

I mean, you have 3 diodes, 2 dichros and mix by power ratios.
I have seen companies that have specific dichros to split 560-580 wl's, but how would this effect mixing with the RGB?

Not to mention 488-490+nm"s. I have both as well.

Another issue I see with current RGB PJ's and the ILDA standard is the need to control a 4th WL! Now you would have to control RGBY! Would this create a new class of PJ's, control boards and software? As well, a change to the ILDA standard?

Just food for thought...

 

[Benm]

CMY(K) is a substracting color system for print indeed. The main reason to have black in there is so you can use only black pigment/toner to print purely black text and such, which is pretty common. If you printed CMY on the same spot it'd look near black, though usually a bit off.

As for standards: it may require a conversion that could be done in hardware or software.

You could, for example calculate what ratio of RGBY would render the same color as that in RGB, but with part supplied by the Y channel. This is already done in some smartphone displays to up the brightness a fair bit.

And it would add complexity on the hardware side as well, as you now have to align 4 instead of 3 lasers, which could be quite a pain the behind.

This could be offset if you have a system that has a lot of power in the blue though, increasing overal brightness of 'white' greatly when a lack in red or green is the limiting factor.

To get it exactly right you'd need to know the exact wavelengths of all lasers and draw a gamut chart from that, and then overlay the RGB gamut chart over that. Since the gamut with added yellow will always be larger (provided you use the same wavelength for red green and blue), the RGBY system can produce any color the RGB could.

One interesting benefit is, however, getting 'rid' of green. Currently it's hard to produce direct green laser diodes, but if you had something a bit cyan (say 510 nm?) you could mix in the yellow to make the overal output white again.

 

[kecked]

Pangolin has had six line color forever. You forget the Ar/Kr ion days. It’s not a big deal to handle at all and the ilda connector has provision for it.

 

[Grn05gt]

Yes, I see that now. Looking farther into the ILDA standard and the connector pinout and controls, there is seperate inputs for both yellow, cyan and a 3rd/deep blue. I guess this would mean the mfg of the PJ or the control board would just have to add an output interface/connector for the other diodes/colors.

As you said, back in the Ar/Kr days, this was done, but, with an "Acoust-optic modulator". On a new type system with seperate diode and/or DPSS lasers, I would think it would take some extra discrete electonics in the PJ to control the new diodes.

I wonder that if the new yellow and cyan diodes get more powerfull, some mfg may incorpoate them into PJ's. Just like is being done in some TV's and and other display devices like Benm stated. As far as adding them to existing PJ's, it may be more trouble than it's worth. You would have to tap into the "user defined" channels of the ILDA connection on/at the control board some how with proper drivers for the diodes as well as add and align the extra dichros. I think it would be cool, but an awfull lot of work.

I think I'll stick to using my yellow and cyan diodes on Lumia and other devices for now.