Changeip, with 5,000 nits you may need some sunblock.
I saw that unit on Digikey for around $40. What driver do you plan to use? What is the cost? Will you have thermal issues?
I was happy to learn of the ECR equation from the
Rugged PC Review. I would like to know the reflectivity rating for the MicroTouch ClearTek II or the Elo IntelliTouch SAW touchscreen surfaces. The ClearTek has a an Anti-Glare (AG) coating, which diffuses light, while what is really needed is the Anti-Reflective (AR) coating, which cancels the reflected light. It appears that this is custom optical work.
The 8.4" NEC panel spec states it has an AR coating but doesn't state a hard reflectivity rating. Using data from the article, with let's say it has a reflectivity of 1% (half of normal untreated panel). The naked surface of the glass touchscreen would be 4% for top and 4% for bottom. This yields a total reflectivity of 9%.
For the stock 8.4", the ECR would be 1 + (600 / (10000 x 0.09)) = 1.6:1.
For the 8.4" with upgraded 5,000 nit backlight, the ECR would be 1 + (5000 / (10000 x 0.09)) = 6.5:1.
The viability of the upgrade would depend on the ST-NLT technology and where it will start to wash out. This is why I am reluctant to use too much back lighting. With a default CR of 600:1 on the 8.4", I'm thinking it would fare well with double, maybe triple the luminosity. Is there a rule of thumb here with current contrast ratio and max brightness limits?
I just don't look forward to a DIY backlight project with custom housing. This is why the ERG solution was so promising. Optical bonding would drop the reflectivity to 4% so ECR = 1 + (600 / (10,000 x 0.04)) = 2.5:1. The 5000 nit would be 12.5:1. Keep in mind that I am a total greenhorn and my reflectivity numbers could be way off.
Turbocad6, I should create an OEM integrator shell website, say Thermoptic Industries International, with one of the cheap hosting companies, a few clicks deep, with a pay-as-you go mobile number. Request a plant tour and on-site visit up front, but only after you have reviewed purchased sample to verify their competence. You know, before you serious consider them for the 1K/month kiosk production ramp.
