Defaults are lambda = 550 nm (green visible light), D = 100 mm (small telescope), F# = 8 (typical photographic lens) and R = 1000 m. Larger D shrinks the diffraction angle and lets the system resolve finer detail at long range.
Bright central disk = Airy disk / dark concentric circles = first and second dark rings (zero intensity) / faint outer rings = secondary lobes. About 83.8% of the total light sits inside the central disk. Colour follows the visible-light approximation of lambda.
X = radius from centre r [microns] (focal-plane scaling) / Y = relative intensity I/I_0 / blue curve = Airy function [2 J_1(x)/x]^2 / red dashed lines = first dark ring (Airy radius) / yellow band = central disk region.
The Fraunhofer diffraction pattern of monochromatic light of wavelength $\lambda$ passing through a circular aperture of diameter $D$ is given in terms of the Bessel function of the first kind, $J_1$.
Airy intensity pattern (with $x = (\pi D/\lambda)\sin\theta$):
$$I(\theta) = I_0\left[\frac{2\,J_1(x)}{x}\right]^2$$Angular radius of the first dark ring (the first zero $x = 3.8317$ of $J_1$):
$$\theta_\mathrm{Airy} = 1.22\,\frac{\lambda}{D}$$For focal length $f$, F-number $F\#=f/D$ and distance $R$ the Airy radius becomes:
$$r_\mathrm{focal} = 1.22\,\lambda\,F\#,\qquad r_R = \theta_\mathrm{Airy}\,R$$The Rayleigh criterion fixes the smallest resolvable angular separation at $\theta_\mathrm{Airy}$. About $83.8\%$ of the total light energy is concentrated inside the central Airy disk (the rest leaks into the secondary rings), and that fraction also caps the Strehl ratio of the optical system.