A planar light with a wavelength of 500 nm is dropped on two long slits with a width of 0.10 mm with an interval of 0.20 mm on a light-proof screen. If the curtain is 1m away from the slit and 0.5 m away from the Weld slit, does the resulting pattern correspond to Fraunhofer diffraction or Fresnel diffraction? How many interference fringes are visible in the bright central strip.

A planar light with a wavelength of 500 nm is dropped on two long slits with a width of 0.10 mm with an interval of 0.20 mm on a light-proof screen. If the curtain is 1m away from the slit and 0.5 m away from the Weld slit, does the resulting pattern correspond to Fraunhofer diffraction or Fresnel diffraction? How many interference fringes are visible in the bright central strip.