Results of LCD investigation
I ordered a couple of Optrex STEP character LCD displays from DigiKey to compare image quality after some bad experiences with LCDs (of various devices) in cars. I wanted to see if we can do better than generic a back-lit LCD.
After writing some control code for a ATMega128 dev board I had laying around (reading busy flag in 4bit mode is interesting...) and making some custom characters to pretty things up (useful for arrows, and symbols), I connected the displays and took some representative photos. They all look a little better in person, particularly in the sunlight - my photography skills aren't up to this task.
Anyway, the main thing here is that the Optrex STEP displays are visibly better in all conditions, particularly the crispness and angle of viewing. Only downside was a just-noticeable flicker in sunlight from the custom characters (visually similar to CRT monitor flicker) most noticeable on the white on back display.
Under inside conditions, black on white looks great, with widest viewing angle range... I'd compare it to VFD. In direct sunlight however, the transflective black on white display looks better, and it doesn't matter how bright the sun gets - I've ordered another one so I can check it with a working backlight. In the car at night, I expect most folks (at least, those who don't drive convertibles) would prefer the white on black... it's always a compromise.
Also, Read The Fine Manual - I assumed 5V LCD had a 5V LED backlight, but it didn't. So no test of the backlight on the transflective STEP display (it looked good for the 15 seconds before it burned out)
VEMS yellow/green shop display
Black on white (no backlight, see above)
White on black
