(green restocked very soon)
Offline
Thanks guys! And thanks for the link, Wilba... your biversion method is super sleek. 
Looks a lot more intimidating, honestly, but I guess for the most part it's the same mod with a different inverter...I really like the way you mounted it on the board. I think I'm gonna want to practice soldering something else before I start in on my DMG, though... I bought a spare, but I don't really want to break anything.
Glad to hear the green kits will be back in stock soon, kitsch! I guess I'll be grabbing one soon after they make their return. 
Really looking forward to trying out the EL screens too, in time.
Offline
Seattle, Wa
I am also new and have a couple questions on this topic, maybe someone here can answer them?
Can someone describe to me fundamentally how biverting is preferable? If you invert the screen twice, what is different about the biverted configuration, wouldn't it be back to normal? How is the physical inversion (rotating the polarizer) different from an electronic one(Patched LSDJ or an IC)?I know it is supposed to give better contrast, but does the effect only work with a backlight, how does biverting affect performance if the backlight was off?
Is a biverted gameboy harder to see using only reflected light? That question is more about if this makes the screen look better, and would have cost Nintendo nothing why didn't they design the screens this way, is there any downside to inverting the screen twice?
I've seen it compared to a gameboy pocket screen, my pocket side by side with a DMG has much "blacker" pixels, does a biversion achieve this on a DMG?
Last edited by Retrovolvo (Mar 29, 2012 7:56 am)
Offline
Melbourne, AU
Using an inverted polarizer gives a better contrast on DMG, I forgot the science behind it, though 
It is just physically different than merely swapping pixel colours in software (i.e. just changing LSDJ's "LOOK" param) or via an inverter IC.
The "bivert" mod is just using an inverted polarizer and also inverting the bits going to the LCD. So it is back to normal in the sense that pixels that should be dark are dark, but now there's an inverted polarizer in play, giving you better contrast.
Here's the different backlights that kitsch-bent sells, showing normal, inverted polarizer, and biverted.
Note the big difference for the white ones.
AFAIK inverted polarizers don't work well with reflected light, and if you're modding a DMG LCD, you've already committed to using backlight all the time, as you have to remove the mirror film along with the existing polarizing film. Since Nintendo planned not to use backlights, they used the best thing for a reflective LCD, which is a "positive" LCD polarizer.
Last edited by Wilba (Mar 29, 2012 12:00 pm)
Offline
That picture makes so much more sense now! It never registered to me why there were three pictures of each color... of course the third one is biverted. How silly of me. 
Thank you for pointing that out! That makes this picture about as useful a reference as I can get, I'd say...Looks like pink, white, yellow and green are the most contrast-y after biversion. I feel pretty cemented in my choice of green at the moment, given the evidence gathered. Thanks for the question, retrovolvo... the answers provided were helpful to me, too.
Offline
matt's mind
Wilba got it.
polarization basically takes the light that would normally be entering your eye in a messy fashion, and 'straightens' it out. this is the reason that polarized sunglasses are used for fishing, it allows you to see past a lot of the glare on top of the water and into the water. this film can be polarized in (three) different ways: linear, circular, or elliptical. Its just a change on how the light exits the film, its polarized differently.
Linear polarization is used in these LCDs. This picture illustrates linear polarization. circular polarization graph would look almost the same, except the left side would (and should be now) more jumbled looking, and the right side it would come out as a nice spinning combination of the x and y axis of the light, spinning like a corkscrew shape. elliptical, same on the left just spinning an ellipsis on the way out.
found better pics. actually, on the 'trashbaby' theme they're hard to see. open in a new tab if you can't see the black.
here's linear:
circular:
elliptical:
Offline
Seattle, Wa
Wilba wrote:
AFAIK inverted polarizers don't work well with reflected light, and if you're modding a DMG LCD, you've already committed to using backlight all the time, as you have to remove the mirror film along with the existing polarizing film. Since Nintendo planned not to use backlights, they used the best thing for a reflective LCD, which is a "positive" LCD polarizer.
Thank you, that's exactly what I was asking. I've seen DMGs with switched backlights, and I was wondering if the screen would be worse than a normal one with the backlight off.
Offline
Melbourne, AU
Here's another explanation of how LCDs work: http://www.nobelprize.org/educational/p … s/history/
TL;DR version:
Offline
would a pro sound mod of some sort eliminate the whine/hum caused by the EL backlights?
Offline
also... which LED backlights do you guys prefer... kitsch or nonfinite? (not trying to start a war... just an honest query)
Offline
Honestly, the panels are very similar. Both have the bright spots from the bottom. the nonfinite ones require a separate resistor.
I suggest a white inverted panel, and then inverting the LCD data. This will result in a very black and white looking screen.