For an aperture of `2mm` and wavelength of `500 nm`, Fresnel distance is

The width of an aperture is 4 mm and wavelength of light illuminating it is 600 nm. Find the distance up to which ray optics is valid.

For an aperture of size a illuminated by a parallel beam of light having wavelength 1, the Fresnel distance is:

For an aperture of size a illuminated by a parallel beam of light having wavelength 1, the Fresnel distance is:

What is the Fresnel distance for an aperture of 3 mm and wavelength 400 nm?

Estimate the distance for which ray optics is good approximately for an aperture of 2mm and wavelength 500 nm.

Estimate the distance for which ray optics is good approximately for an aperture of 2mm and wavelength 500 nm.