Hi everybody,
i think this is my first post on Arduino Community but i often read your suggestions to help me in my projects... so thx! 
Let's get back to us.
I need to make a bright display that must show an interface masked by a plastic surface (like this more or less http://technabob.com/blog/wp-content/uploads/2008/01/white_led_clock_2.jpg) with an high resolution in a 10cm to 10cm surface.
What do you think is the better solution to achive this?
Thx all for your support!!!
R*
How high is "high resolution"? Pixels
A monochrome display or colour?
You can get quite a good effect with baffled LED's behind a paper mask on a tinted plastic (see pictured here) and I would think you could do the same sort of thing with a simple OLED display where the pixel is the light source. I don't know this would work as well for TFT displays that have a backlight but I have not tried.
Another possibility would be an eInk display
Thx Riva,
i was thinking to a led matrix as the one you use for your amazing clock but i think is not enough hi res because i need also to print text.
Oled display seems the better solution because eInk is not enough bright to pass over a plastic surface.
Do you know where i can buy a large Oled display? I've found only small one like this
R*
robbcasanova:
i was thinking to a led matrix as the one you use for your amazing clock but i think is not enough hi res because i need also to print text.
The matrix in my clock was custom built and it did not need to be high res but if you used something like these you could stack them in a 3x3 square and have a resolution of 24x24 pixels.
It is difficult/impossible to get large OLED displays as you need but maybe they could also be stacked like the LED matrix's.
Yep,you are right. I think stack some led matrix could be the right solution.
Adafruit has this very tiny matrix Miniature Ultra-Bright 8x8 White LED Matrix : ID 1079 : $7.50 : Adafruit Industries, Unique & fun DIY electronics and kits.
Thx.
robbcasanova:
Adafruit has this very tiny matrix Miniature Ultra-Bright 8x8 White LED Matrix : ID 1079 : Adafruit Industries, Unique & fun DIY electronics and kits.
Nice, at 20mm wide you could stack 5x5 and that gives a 40x40 pixels display. The MAX7219 would be a good driver chip though chaining 25 in a row will probably be problematic as most people report problems after about 4-8 in a row but maybe they have found ways to overcome this with buffering chips?
Neat, that clock is not unlike the effect I would like to get with my own gauge project -- http://forum.arduino.cc/index.php?topic=315899.0 -- though I was thinking that a tinted, non-refective plastic surface would provide better readablity in sunlight.
I am also looking at those same Adafruit mini 8x8 matrix modules, thinking that I could use two to display four digits in a 8x16 matrix using a 4x6 or 4x8 font. In my case, I would have liked to use normal alphanumeric LEDs but they won't fit inside the neopixel ring that I would like to use for analog readout.
Would an alphanumeric LED work in your case, maybe one of these?
