A projector's aspect ratio refers to the ratio between the width and height of its projected image, in which the width is usually the first number and the height is the second number. For example, a 4:3 display could be 16 inches long and 12 inches high, or 20 inches long and 15 inches high.

Aspect ratio by its very nature describes the shape of the rectangle. Nowadays the most popular aspect ratio for a high-definition TV set or consumer video display is 16:9 and that is precisely the reason almost all Nebula projectors’ aspect ratio is 16:9. Due to Nebula projectors’ aspect ratio, watching videos or movies on a Nebula projector will bring you the same wonderful watching experience as on a TV or computer screen.

The aspect ratio for Nebula projectors is attached below for your reference: