import numpy as np

"""
lens makers equation:
1/f = (n-1)( 1/R1 - 1/R2 + (n-1)d/nR1R2 )

with
f = focal length
n = IOR (quartz glass = 1.458)
R1 = radius of curvature 1
R2 = radius of curvature 2
d = thickness


F-stop = f/D


variables:
D_lens
D_ground
"""

