PG-MB60X. Version 1.2 - Sharp Projector Handy Guide. Page 21

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This is the physical component within the projector that creates the image. It can be either an
LCD panel or DMD device.

Calculating Image Size and Throw Distance using Focal Length 
If the throw ratio of the lens is not available then the focal length can be used to calculate the
image size or throw distance, however the dimensions of the display panel are needed.

To calculate the throw distance for a pre-defined image size:

Example
Calculate the throw distance required to give a 2.5m diagonal image. The focal length of the
lens is 44mm and the DMD panel is 20.32mm (Diag)

To calculate the image size from a set distance:

Example
Calculate the image size (diag) at a throw distance of 3m. Focal length is 63.8mm and the
LCD panel is 63.8mm (Diag)

f Focal Length

Display Device

Screen

Focus
Lens

Zoom
Lens

       44mm 

             x 

2500mm (diag)  =  5413mm  (5.413m)

20.32mm (diag)

 

3000mm 

        x      33.25mm (diag)  =  1563mm  (diag)  (1.563m)

63.8mm (diag)

Image and Panel Size must be of the same dimension. i.e. Image and Panel

diagonal measurement OR width measurement.