Annular Beam Shaping in Multiphoton Microscopy to Reduce Out-of-Focus Background

Figure 2

Schematic view of the coordinates for theoretical simulations; (a) the coordinates used for calculating the Fresnel-Kirchhoff integral. For every point located at a distance from the lens, the contribution from each element on the lens ( = 0) is added; (b) coordinates for considering the out-of-focus signal generated adopting simplified geometrical focusing conditions.

(a)

(b)