From a general point of view the difference between indoor and outdoor screens are the following: 

#1 – Resolution: as the outdoor screens are usually watched from greater distances, they do not need the highest resolution (from great distance the human eye do not discriminate small details anyways). 

The cost due to the big dimensions is therefore compensated by the lower resolution needed to provide a good image quality.

The Virtual Pixel is a technology of image management that allows visualizing pictures of a definition higher than the physical one, thanks to a technique called pixel interpolation? Virtual Pixel technology is able to control every single LED: this particular and exclusive screen management feature allows overlying every single pixel to the next one, creating a so-called Virtual pixel?(a pixel that does not exist but is perceptible by the human eye).

The “definition” is the number of vertical and horizontal pixels that are on the entire screen. For example, some standard definitions are 96×64 pixels (=low definition); 256×192 pixels (=medium definition): 640×480 pixels (=high definition). The definition is therefore related to the pixel pitch, the distance between the pixels.

Gray grades means one color from the most dark to most brightness ‘s grade. More Gray grades mean more color displayed and more definition.

IP65 means waterproof and dust protection. so it can be used outdoor,if the IP54, then will be used indoor.

Driving IC means to control the LEDs current,LEDs usually the constant current 0.16mA to 1.2mA. so it is important for screen to use the good Driving IC.