How to Calculate the Angle to the First Dark Ring in a Laser Diffraction Experiment
What is the angle from the center of the airy disk to the first dark ring in a laser diffraction experiment?
Given data: wavelength of laser light = 632.8 nm, aperture of lens diameter = 1 mm
Answer:
The angle from the center of the airy disk to the first dark ring in a laser diffraction experiment can be calculated using the formula:
When laser light passes through an aperture, diffraction of light takes place. The first diffraction minima occurs at:
[tex]a \sin(\theta) = \lambda[/tex]
Where:
a is the width of the aperture
λ is the wavelength of the light
θ is the angle
Plugging in the values:
[tex]\sin(\theta) = \dfrac{\lambda}{a}[/tex]
[tex]\sin(\theta) = \dfrac{632.8 \times 10^{-9}}{1 \times 10^{-3}}[/tex]
[tex]\theta = \sin^{-1}(0.0006328)[/tex]
θ = 0.0363° (angle of the first dark ring)