LED display for outdoor usage

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Hello dear PJRC community,

First of all, I hope this is in the right forum.

I'm currently in the process of building LED displays for outdoor usage. This is something I'm new to so bear with me :)
The display should measure 1000x700mm with a pitch of between 5-16mm (depending on amount of power), driven by a Teensy 3.6 with the ethernet module, powered by a 12v car battery. I know this size of display draws a tremendous amount of current but thats a problem for later :)

In the first version I've used the WS2812 5050 pixels. They are perfect indoors but as soon as I try it outside, with some sunlight, it completely washes the colors out and it's almost impossible to see the graphics. I've also built a sun shield to protect the display and it somewhat helps but during certain hours during the day I'm still having problems + this is not feasible / possible to have for the end product.

Started doing some research and it seems that most outdoor displays use DIP LEDs instead of SMD so I looked into display modules with DIP LEDs and found the following product LINK.
They look promising. However, I have NO CLUE how to display any kind of graphic on them. It says that it accepts the following signal "AV, S-Video, VGA, DVI, YPbPr, HDMI, SDI", but can the Teensy handle / provide that?

Summary and the final question: Does anyone here av any advice or experience of what kind of LEDs I should use for this project? They need to be visible and not wash out in direct sunlight. They need to be controlled from a Teensy. If possible, it should also be weatherproof.

Thank you for your time!

Regards
 
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As you've discovered, the sun is very bright. One car battery won't supply enough current to light your display for long at levels required to compete with direct sunlight.

You might want to look into the power requirements of traffic lights and scale the numbers to the size of your display.

If low power is more important than using LEDs, you might be better off with different display technology entirely, such as flipping disc displays.

The signals you mentioned are video standards, like you'd find for a TV display. There's been some work for VGA, but you wouldn't get the others out of the box. You'd need something like a BeagleBone Black or Raspberry Pi Zero to drive video unless you want a very challenging electronics development project.

Whatever route you choose, try to find datasheets for the components you are considering. Many of the questions you'll have are best answered by understanding what the manufacturers themselves say.
 
They need to be visible and not wash out in direct sunlight. They need to be controlled from a Teensy.

That will require a very powerful LED.

One trick to make things more visible, which traffic lights usually use, it a shroud to cast a shadow over the light source. It can still be washed out with very bright sunlight, but at least this can help without needing more LED power.
 
Some have gone down this road already. Its a fun project and Here is a shield that you can use to connect to certain kind of panels.

https://www.adafruit.com/product/1902

However If you new to this you are in a steep learning curve especially if you new to MCU's etc. Panels like these use several signal clock lines to function. Google a bit more and you will find others that have evolved code to accommodate different needs and desires. These panels are dense in pixels and require a decent amount of resources. One thing to keep in mind the network connectivity to drive a larger matrix is going to be your challenge. Depending on the size and refresh rate your going to find quickly that the teensy and or coding skills may not be adequate to do the job. I have seen others use the beaglebone or raspberry pi to get the needed CPU and memory resources to drive these matrix panels like your expecting.

Suggestion: If this is for yourself and want to learn... even better! however if you doing this for client or looking to get in the business of LED Signs, then may I recommend going with products already made available and designed for this purpose. There are so many to choose from but if you on the budget and not sure where to start check out http://www.led-card.com I am not recomending that you buy from here, however this place has all the common low priced components out there to build your own outdoor sign.

Offtopic: I have serviced these larger LED signs and they are fun to diagnose and see how they all work. I actually live a few min from a LED sign manufacture and everyonce in a while get some surplus components from (LED's, LED IC's etc)
 
As you've discovered, the sun is very bright. One car battery won't supply enough current to light your display for long at levels required to compete with direct sunlight.

You might want to look into the power requirements of traffic lights and scale the numbers to the size of your display.

If low power is more important than using LEDs, you might be better off with different display technology entirely, such as flipping disc displays.

The signals you mentioned are video standards, like you'd find for a TV display. There's been some work for VGA, but you wouldn't get the others out of the box. You'd need something like a BeagleBone Black or Raspberry Pi Zero to drive video unless you want a very challenging electronics development project.

Whatever route you choose, try to find datasheets for the components you are considering. Many of the questions you'll have are best answered by understanding what the manufacturers themselves say.

The amount of time that the battery will be able to power the display is not a concern since the displays are just going to be on for 1-4hours at a time and if needed, we could just put two batteries in parallel to extend the running time.

I've looked through numerous datasheets and watch pictures and videos but they rarely represent how the LED's look in real life since cameras often have a hard time picking this up. I also think there is more to this than just LED power, like the display I put in the description has small shrouds over each pixel, what viewing angle the LED's have, size of pixels, distance to the glass (if any), glass treatment(like anti glare), what color the pixels are, for instance the majority of the WS2812 are white, maybe the black ones would perform better in terms of contrast in sunlight, etc. etc.
 
Some have gone down this road already. Its a fun project and Here is a shield that you can use to connect to certain kind of panels.

https://www.adafruit.com/product/1902

However If you new to this you are in a steep learning curve especially if you new to MCU's etc. Panels like these use several signal clock lines to function. Google a bit more and you will find others that have evolved code to accommodate different needs and desires. These panels are dense in pixels and require a decent amount of resources. One thing to keep in mind the network connectivity to drive a larger matrix is going to be your challenge. Depending on the size and refresh rate your going to find quickly that the teensy and or coding skills may not be adequate to do the job. I have seen others use the beaglebone or raspberry pi to get the needed CPU and memory resources to drive these matrix panels like your expecting.

Suggestion: If this is for yourself and want to learn... even better! however if you doing this for client or looking to get in the business of LED Signs, then may I recommend going with products already made available and designed for this purpose. There are so many to choose from but if you on the budget and not sure where to start check out http://www.led-card.com I am not recomending that you buy from here, however this place has all the common low priced components out there to build your own outdoor sign.

Offtopic: I have serviced these larger LED signs and they are fun to diagnose and see how they all work. I actually live a few min from a LED sign manufacture and everyonce in a while get some surplus components from (LED's, LED IC's etc)


This is great! I had no idea they provided a Teensy shield for these displays. I already own a couple of 32x32 4mm pitch SMD displays of this kind I will try this path. Just placed an order for the shield! :)

I'm not really concerned about the performance of the Teensy not being enough since I'm more or less only going display stationary graphics, not any animations (just maybe a scrolling text).

Thank you for the link, had a look and it looks like they have exactly the products I've looked into and I will most certainly go down this path! Thank you! :)
 
pictographer, PaulStoffregen and crees, I would like to thank all of you for taking the time to answer my questions and giving me new ideas.

I will post my results and findings here in this thread later!

Thank you!
 
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