The distance between the two slits and the display screen is d, and the distance between the two slits is l. It doesn't matter if the wavelength is outside the λ influence formula. Single slit is only used to obtain coherent light source.
When light encounters obstacles in the process of propagation, it will bypass obstacles and change the straight-line propagation of light, which is called light diffraction. When the size of obstacles is not much larger than the wavelength of light, such as slits, small holes, small round screens, hair, fine needles, metal wires, etc. We can observe the obvious diffraction phenomenon of light, that is, the phenomenon that light deviates from a straight line.
Extended data:
Precautions:
1, instruments and equipment should be handled with care to avoid collision.
2, eyes don't directly to the laser power beam, so as not to damage the eyes.
3. Turn on the laser power supply, adjust the slit width of the single slit disk, let the laser beam pass through the single slit, and pay attention to the display screen. Then you can see a set of bright and dark stripes appear on the display screen, the stripes in the middle are the brightest, and the brighter the stripes are toward the two sides.
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