principal plane การใช้

For a thin lens in air, the principal planes both lie at the location of the lens.
The GAIA plane is the principal plane obtained by applying a principal components analysis to the set of actions in this space.
For example, because it is not practical to locate the principal planes of such small lenses, measurements are often made with respect to the lens or substrate surface.
Note, however, that for a real lens the principal planes do not necessarily pass through the centre of the lens, and in general may not lie inside the lens at all.
If the aperture is right next to the lens, ( technically, at one of its principal planes ), then the area of the image is not affected by the area of the aperture.