Question

] A hang glider flying 195 m above the ground looks down on two beacons emitting light with a wavelength of λ = 650 nm. If the glider’s pilot has a pupil diameter of d = 1.5 mm, what is the minimum seperation along the ground between the beacons such that the glider will see 2 distinct beacons? Reminder: The Rayleigh criterion calls for the angular separation to be at least the diffraction minimum angle.

Answer 1

From Rayleigh criterion, angular separation for between two points just resolved is   

Wavelngth of light

Height of glider from fround,,

Diameter of pupil

If the separation between points is ,

For small angles ,

then for human eye,

Minimum separation along the ground between the beacons is