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Topic: Looking for a Display for direct sunlight readable (hard sun) (Read 180 times) previous topic - next topic

fabianbambam

Hello guys, I saw some topics here about this, but I do not see displays that are friendly to work with.

I'm looking for a display for Direct sunlight.


Specifically I'm looking for:
- Direct sunlight readable (hard sun).
- Refresh capable of lap timer count.
- Medium size 3" to 4"

Did you know any options that I could look for? I want to implement it with a board like Arduino UNO, ESP8266, ESP32, Adafruit Feather boards, etc. Boards that I could use with Arduino IDE.


I tried with Epaper displays but they have too slow refresh rate and was very hard to look for a way to make it faster.

Thanks for your help and support, I'm looking forward to read your suggestions

Nick_Pyner

I think you have two choices
1.  a reflective or transflective type LCD. The only one that I am aware of is the Nokia 51110, which is reflective.
2.  a high power LED  of some sort.

cherk

Have look at Newhaven Displays,

www.newhavendisplay.com

olikraus

With your size constraints, I suggest the reflective DOGM240N or the DOGXL240N.
I had used the reflective DOGS102N in the history. More/harder sunshine --> better display.

If price is an issue, look for transflective displays:
https://www.aliexpress.com/item/3-2-inch-20PIN-SPI-COG-256128-LCD-Module-ST75256-Controller-White-Blue-Backlight-I2C-Parallel/32818052799.html

Transflective display are not as good as reflective displays under heavy sunshine, but include a backlight which allow use in dark environments also.

Oliver




fabianbambam

Hello, thanks for your replies and your time!

olikraus, I saw you on older posts like: https://forum.arduino.cc/index.php?topic=261974.0

and seems that those EA DOG displays are very interesting. However, I'm concern about the refresh rate.

Needs to be possible to display a stopwatch or a timer with good visilibity with a format like: "HH:MM:SS.mm"

That's why I need a fast refresh rate. However, I saw this one, for example:

EA-DOGXL240N-7

I could not find the refresh rate.

I wanted to use Epaper displays but they are too slow for this task, the one that I used has a refresh rate of 300-400ms... This is too slow for what I want to do.

Where could I find the refresh rate? At least in the datasheet or the website?

I briefly reviewed the datasheet but I would checked today again. Maybe I miss it.

The other that you suggest, looks like it's not reflective (at least because it seems to have a backlight) and maybe is not readable with direct sunlight:

https://www.aliexpress.com/item/3-2-inch-20PIN-SPI-COG-256128-LCD-Module-ST75256-Controller-White-Blue-Backlight-I2C-Parallel/32818052799.html

TFTLCDCyg

Maybe this:

EVE2 NHD 3.5" 320x240, SPI, FT813 chip driver

or this

EVE2 NHD 4.3" 480x272, SPI, FT813 chip driver



Setup: NHD 4.3" + Teensy 3.6 + microSD sandisk extreme 32 Gb on SDIO


olikraus

Quote
I could not find the refresh rate.
The dogxl240 has a 8MHz SPI interface. There are 240*128=30720 pixel available, so as a max refresh rate there could be 260 frames per second (FPS). Of course there is some overhead and some other timing aspects have to be considered, so it might be lesser than this.

However, the real limitation for the refresh rate will come from the selected interface and the microcontroller (Arduino Board).

I have just tested U8g2 Software emulated SPI (which is known to be very slow) on an Arduino Due in U8g2 full frame mode and received about 2 FPS. I assume with hardware SPI (also supported by U8g2) it will be around 20-30 FPS.

For an Arduino Uno with hardware SPI and u8g2 page mode, you probably should get around 5 FPS.

As a conclusion, I guess, that all Arduino boards should be able to refresh within 200 ms under the assumption, that you use hardware SPI.

If not, there still are some tricks to make it faster with u8g2... just contact me for this.

Quote
The other that you suggest, looks like it's not reflective (at least because it seems to have a backlight) and maybe is not readable with direct sunlight:
Yes, it is not reflective, but still it is readable (but of course not as good as reflective). I mean, there is always a tradeoff. It aliexpress display is cheaper and has a backlight (so it is readable in the dark also).
It also depends on your intended usage.
For example I just did the FPS tests with a transflective version of the DOGXL240 in my lab with not so bright artificial light. But I also did not turn on the backlight of the DOGXL240: It is readable, but definitly not as good as a reflective version under the same light conditions.




Quote
EVE2 NHD 3.5" 320x240, SPI, FT813 chip driver
Of course this is an option, but still a TFT display is not as good readable as a black/white reflective LCD under bright sunshine.





fabianbambam

Quote
As a conclusion, I guess, that all Arduino boards should be able to refresh within 200 ms under the assumption, that you use hardware SPI.
Sounds good.

I was testing with the 296x128, 2.9inch E-Ink display module

They are the best for sunlight to me, however, it is not good with the refresh rate specifications, full refresh = 2 seconds and partial refresh (a part of the screen ) = 0.3 seconds for the 2.9 inch version, in conclusion. They could work for applications that do not required a fast update of the screen. Excellent with power consumption too.

I will keep looking at this EA Dog displays, I will try to reduce the price with a smaller screen.

I agree that SPI interface could give the fastest data transfer as is the fastest over I2C and UART.

Quote
If not, there still are some tricks to make it faster with u8g2... just contact me for this.
I guess I would try with hardware SPI, there is no reason to try it with software simulated SPI when with hardware we could get better results. If there are ways to look for a way to make it even more faster I could contact you if you don't bother. Thank you for your consideration.



Quote
Maybe this:

EVE2 NHD 3.5" 320x240, SPI, FT813 chip driver

or this

EVE2 NHD 4.3" 480x272, SPI, FT813 chip driver
Thanks for your suggestions, however, as I understand with my research, the best option is the reflective displays, they are better suited for applications with direct sunlight contact.

They are not too "arduino familiar" (?)

Awesome setup  btw

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