(Solved):   single-slit diffraction In Fraunhofer single-slit diffraction, the width b of the single ...

 

single-slit diffraction

In Fraunhofer single-slit diffraction, the width b of the single slit is \( 0.60 \mathrm{~mm} \) and the focus \( f \) of the lens is \( 0.40 \mathrm{~m} \). When the parallel light illuminates the silt, we observe the bright fringe on the \( P \) point (the distance \( x \) between \( O \) and \( P \) point is \( 1.4 \mathrm{~mm} \) ). Find (1) the wavelength of the visible light; (2) the order for the bright fringe at \( \mathrm{P} \) point; (3) According to \( \mathrm{P} \) point, the number of half-cycle bands for the wavefront of the slit.