I am considering to use Arduino for a prototype I have in mind. I've read and seen many tutorials on Arduino and seems very straightforward as I am a programmer. Keep in mind I have 0 experience with Arduino or electrical engineering in general.
My requirements are to be able to display a picture on a 7" LCD screen (bigger is also fine). No need for touchscreen. What should I take into considerations when buying such a display? I found different products ranging from $48 to $200.
Why such a big difference between those two? Any other displays I should consider? Anything else I should consider? Connectors, software libraries, etc?
there is difrent between OLED display and LED btw
anyway if this project just for fun use your home lcd display, you don't need any other sheild with your arduino bourd just make like this project
The difference between those two displays is that the cheaper one is the basic type of a LCD module. You have to find a library (or create one) to draw lines, text, etc. Also if you have troubles running it, I guess your only friend will be google.
The display from 4DSystems has a graphic processor (as oppose to a graphic controller) and that LCD module can run on it's own without Arduino. The company provides an IDE where you can basically drag and drop buttons, pictures etc and not worry how it will be drawn. The LCD module also has GPIOs, I2C, multiple SPI and Serial channels, analog inputs, timers, etc. The company also provides support (not sure how good or bad it is) and probably a better warranty. I assume you can drive the display the same way as the cheap one (e.g. via SPI) but it's processor would be bored while your Arduino sweating while trying to draw a straight line. So I don't know what your project is but if you just need to hook up a few buttons, maybe read some analog inputs or some other basic things then the display can do it on it's own. The disadvantage is that you have to learn a new programming language (whatever they use to program the LCD) but I guess it should not be too hard (especially if you're a developer). Anyway, hopefully that explains the price difference a bit.
So if you go with the cheaper option these are the things I would consider:
are there any available arduino libraries that support the LCD controller?
what interface do you want to use (SPI, parallel 8bit, parallel 16bit, etc), has library, speed and number-of-pins implications
are you ok how fast is it gonna draw? Btw. you did not mention what arduino you want to use, if it's one of the AVR ones, like Uno, Mega, Mini Pro,... then drawing on an 7" display (assuming 800x480) will in general be slow...but it might be ok for you so it depends on what you are after...
maybe type of the LCD (if viewing angles matter to you), the cheapest ones are not really great when you look at them from an angle (black becomes gray etc.)
the price I guess...
Btw. buydisplay.com seem to have some nice (customizable) displays (same seller as in your ebay link)