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easily viewable cheap LCD in bright glaring sunlight? Answered

I recently bought the cheapest screen I could on amazon for around 20 or so dollars for use on my quadcopter, it is a really crap quality display (only 480 x 272 resolution, and very poor color reproduction, viewing angles, and contrast) but it does serve the purpose of a FPV display for my quadcopter.

However, I remember my old faithful flip mino camera as well as my old palm centro phone which had some type of semi-reflective LCDs on them! The displays could easily be seen in direct sunlight even with the brightness set to the minimum! They seemed to work a bit like calculator LCD displays, where they work on a basis of reflection, but also have backlights in them. To verify that the display on that flip camera does indeed reflect light back, I charged it up and turned it on with my 2000 lumen LED torch shining directly at it. images on my GS3's AMOLED panel would only be visible with the brightness cranked wayyyy up, and similarly on most LCD displays. They just could not handle the same way the flip camera did! You could clearly make out a picture on the flip camera display even when it was charging and the backlight was 100% off!

What would I be searching for to find a display with a composite video input capible of being viewable in direct sunlight like this? Might it be possible to modify my current LCD to make it more viewable in direct sunlight?



I know this post is quite old but I'm currently working on a sunlight viewable LCD. I'm planning to make a digital dashboard for my racecar, sorta like AIM racing display. The idea is I'll buy a panel that fits, strip it of the led backlight layer, and using, probably milky acrylic sheet and high power LEDs (cree or similar) make a new, ultrabright, and automatically dimmable one. At least that's the theory...and maybe a candidate for a first instructable :)

THing is though I do not really want to pay more than $40 for a 5 to 7 inch monitor, for more than that I can deal with what I have. I wonder what would happen though if I take the LCD apart, remove the dim LED backlight and replace it with a light pipe facing the sun, so ambient light is directed into the LCD matrix instead. Might be worth a shot!

If you want to go cheap you won't be able to see in the sun.
There is a reason why these screens are so expensive...
And directing sun light instead of back ligh won't solve the problem of not being able to read the screen if the sun hits it.
It will only make things worse on a cloudy day when your display turns dark.

I decided to try the simplest solution, "overclocking" the LED driver that I made to drive thethe backlight really hard. This did the trick, as the screen is now easily viewable with direct sunlight!

The idea was to make the brightness of the screen a function of the amount of light hitting it, hopefully emulating the screen on the flip camera and palm centro phone that is reflective. I do not think the LCDs on those devices was particularly expensive, and they would work fine I think for my use.

I already destroyed the screen once with reverse polarity, luckily the 5V 2A voltage regulator onboard took the beating and saved the digital/mixed domain stuff. In the process of building up a replacement switching buck regulator for it, I killed the boost converter responsible for generating the 30V or so necessary to drive the 6 LED series, and had to make another custom boost converter to make the screen work again. This was about a day's worth of work (really I was not expecting it to be so difficult, and really did not feel like waiting for shipping on another unit and waiting half a week. Yes I'm that impatient.)

I might be able to hack the screen by removing those LEDs entirely and adding maybe a 1000 lumen CREE XML LED or 2, or maybe just totally overdrive the current LEDs to see if I can make it so that I can at least make out what is on my FPV monitor.


2 years ago

I discovered that the purpose-designed LCDs go by the term "transflective LCD" but they seem to be some sort of niche product only made by a few companies, and the videos shown on youtube of one of these products really blows me away! But the price is in the thousands, several orders of magnitude more than what I am willing to pay.