Question

A cell phone screen shows a green light (wavelength=555nm) from two adjacent pixels an otherwise blank screen. the cell phone screen has a resolution of 1080 pixels by 1920 pixels and is 10.80 cm wide and 19.20 cm long, respectively. each pixel could be considered as an individual light source. how close to the screen do you need to be to see the individual pixels? include a diagram of the problem. (assume the diameter of the eye pupil is 0.925 cm)

Answer 1

The 10.80 cm side of the screen contains 1080 pixels

So, the distance between two pixels is

The diffraction limit resolution of the human eye is approximated by

Using the wavelength of 555 nm and the diameter of the pupil about 0.925 cm

The distance between the eye and the screen can be calculated using

So, the screen should be at a distance of 1.366 m to resolve the pixels.