Diffraction Pattern Analysis Using Helium-Neon Laser

When analyzing the diffraction pattern produced by a helium-neon laser with a wavelength of 633 nm illuminating a single slit, the distance between the first and second minima in the pattern was found to be 3.75 mm. To determine the width of the slit, we can utilize the equation for the position of the minima in a single slit diffraction pattern.

The equation for the position of the minima in a single slit diffraction pattern is given by: y = λmD/d, where:

• y is the position of the minima,
• λ is the wavelength of the laser (633 nm),
• m is the order of the minima, and
• D is the distance from the slit to the screen (1.50 m).

The distance between the first and second minima (3.75 mm) can be expressed as the difference in the y positions of these minima. By using the given values and solving the equation, we find that the width of the slit is 0.25 mm.

Therefore, based on the analysis of the diffraction pattern and calculations, the width of the slit in this experiment is determined to be 0.25 mm.