I am putting together a carputer for a convertible car and I need to have a display that will be easy to read in direct sunlight, as well as during the night.
I will not need to print advanced graphics, just basic info like heading, temperature, voltage, clock, etc.
I had my mind set on an OLED display but I found some tutorials mentioning that it's not great in direct sunlight.
Anybody who has tried various displays can provide some advice if I should go with TFT or OLED?
Thanks in advance!
None of them.
Try a transflective LCD or ePaper display.
ePaper has a slow refresh rate, from what I read so far, so I don't think that will work.
Will research a bit to see what a transflective LCD is. Thanks!
TFT requires back light, can’t see how it is going to be good in sunlight, OLED is already better but the glass reflects on its own so if you can cover it with some non reflective coating
I am not sure whether his TVR is a convertible, but @450nick is building a similar project, maybe take a look at what he is using.
Braille
OLED was my initial choice, but from what I read so far, direct exposure to sunlight will damage it. That's why I am having second thoughts.
Thanks, will take a look!
direct exposure to sunlight will damage many things
Funny, almost. I don't know braille.
Yeah, true. It's not supposed to last a life time 
You don't want your date seeing jumper wires all over your dashboard...
Thanks Bill! Indeed I am... Coming along quite well now
I'm not really building a carputer though, I've built a carputer before many years ago (I think around 2004/2005!) which worked really well for many years. It was a windows XP computer in small aluminium case connected to a 8" touch screen TFT display which I fibre glassed into a replacement dash panel that I got from the scrap yard. I ran some carputer software that booted directly without showing windows, and used a serial port pin raised and lowered by a startup script to trigger my audio amplifiers to come on after the computer had booted. It had GPS, wifi, 3G internet and a 1500w sound system wired up to it so it worked as an internet radio, had a all of my music in an easy to use touch jukebox and worked really nicely!
The TFT wasn't a major problem but then again it was a tin-top car so not so much light around. You can buy lots of different displays which are good for in-car use from carputer component websites (you even could back then!)
What I'm doing is slightly different. I'm building an integrated dash pod to incorporate an analogue looking rev counter, speedo, fuel and temp gauge (I like mechanical things ), then I've built in a tiny 32x16 OLED screen to display things like OBD2 information, other sensor data (temps, voltage etc), warnings, odometer etc. It does not handle entertainment, just information for running the car - this is more than bright enough for a convertible car. For audio, I've designed a bluetooth board that allows high definition bluetooth to be streamed in optical SPDIF straight to the amps with a very tiny hidden volume control, play/pause and skip button to totally hide the traditional head unit, then I've designed an aluminium dash piece that will hold a wireless magnetic charger to securely hold and charge my phone in landscape format. This will handle sat nav and media streaming to the audio system and will hopefully be future proof the design.
If you'd like any info on either project or some other answers to questions that I can help with then I'd be happy to help.
I also think an OLED will be fine. You may have noticed most every type of display in auto's have a hood over them to help shield them from direct sunlight. If you do the same it should last well enough.
Well, our Hyundai I20 has such a display on the dashboard, shaded.
The problems is that because it was "trendy" some ten years ago, it is illuminated by blue LEDs. Basically that is an extraordinarily stupid idea as it is near invisible in daylight even at maximum illumination, however if the sun shines in from the side and directly on the display, the (active) segments (only) are perfectly visible.
I read a bit about your work, interesting stuff. I am a beginner for now so my plans are a bit simpler, but I might "steal" some info from your topics in the future.
Well, seeing all the different opinions I have ordered two cheap displays from Aliexpress, one OLED and one TFT. Will test both and if this thread is still open by the time it's warm outside I will revert back with the results.
I wonder that noone mentioned reflective LCDs.
From my persprective this is the best choice for displays. There are three different types of LCDs: LCD Modes: Reflective, Transmissive, Transflective | New Vision Display
Reflective is exactly the one you need for direct sunlight: More sun even better contrast!
For example the DOG displays from EA include "reflective" displays (for example the DOGS102W https://www.lcd-module.com/fileadmin/eng/pdf/grafik/dogs102-6e.pdf)
Oliver
I mentioned transflective, post #2.
No doubt, transflective will work under sunlight, but reflective are even better because they are optimized for direct sunlight.