Projector Throw Distance
Calculate a projector's mounting distance from the image size, or the image size from the distance, using the throw ratio (fixed or with a zoom range) and the aspect ratio. All in your browser.
How it is calculated · throw ratio and aspect
1. The throw ratio is the
distance divided by the image width (not the
diagonal): throw = distance / width.
2. Width and height come from the diagonal
and the aspect: width = diagonal · aspW / √(aspW² + aspH²)
and height = diagonal · aspH / √(aspW² + aspH²). At 16:9
the width ≈ 0.8716 · diagonal and the height ≈
0.4903 · diagonal.
3. Distance from size:
distance = throw · width. Size from distance:
width = distance / throw, then
diagonal = width / (aspW / √(aspW² + aspH²)).
4. With a throw range (zoom) there is a
minimum and
maximum distance (or size). Conversion:
1 in = 0.0254 m.
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