The highest resolution of the Acer X1140 is SVGA (800x600). That's 53% less resolution than a WXGA (1280x800) projector, which is the most common resolution.
A SVGA (800x600) native projector resolution is actually the worst resolution amongst all projectors that have been around for a similar time to the X1140.
Amongst comparable types of projector the best resolution is 1080p (1920x1080).
If the resolution of this multimedia projector is too low for you then you might want to consider the Acer X1240 (XGA (1024x768)) which also has a higher rating.