How to convert equivalent focal length into actual focal length in photography?

The equivalent focal length we are talking about now is based on 135 film:

Actual focal length × (diagonal length of 135 film/diagonal length of the local photosensitive element Line length)

=Actual focal length × ([24↑2+36↑2]↑(1/2)/diagonal length of the local photosensitive element)

=Actual Focal length "Diagonal length" is also called the conversion coefficient. For example, the conversion coefficient of an ordinary Canon SLR is 1.6, and the conversion coefficient of an ordinary Sony SLR is 1.5,...