Astigmatism

The Astigmatism test gives the astigmatism of your system as defined on the picture.



Astigmatism = ç1/Tangential Image Distance - 1/Sagittal Image Distance ç

In detail:

For each sample VIij of the virtual image, the "Astigmatism" gives the mean of the astigmatism for VIij over the EBij samples of the binocular eyebox, expressed in dioptre.

Astigmatism for VIij : For each sample EBij of the binocular eyebox, the astigmatism for VIij is egal to Abs(1/Tangential Image Distance for VIij - 1/Sagittal Image Distance for VIij).

Tangential Image Distance for VIij : For each sample EBij of the binocular eyebox, the tangential image distance for VIij is the distance from the sample EBij of the binocular eyebox to the sample VIij of the tangential image seen from the sample EBij of the binocular eyebox. This distance is expressed in meter.

Sagittal Image Distance for VIij : For each sample EBij of the binocular eyebox, the sagittal image distance for VIij is the distance from the sample EBij of the binocular eyebox to the sample VIij of the sagittal image seen from the sample EBij of the binocular eyebox. This distance is expressed in meter.

Note: In the plugin, the dynamic distortion of the sagittal and tangential images is computed in three dimensions.

The result of the computation is displayed as a table that contains the "Astigmatism" computed for each sample VIij of the virtual image.



In particular, you can notice that:

  • There is one table result by configuration created.

  • Each table has the size of the sampling of the virtual image.

  • The test also displays a sum up, for each configuration, of the Average, the Standard deviation, the Minimum and the Maximum of the value contained in the table.