Final answer:
Moire fringes are an interference pattern most commonly seen when doing double-slit diffraction experiments or when light passes through closely spaced slits or a diffraction grating.
Step-by-step explanation:
Moire fringes are an interference pattern most commonly seen when doing double-slit diffraction experiments or when light passes through closely spaced slits or a diffraction grating. These fringes are formed due to the constructive and destructive interference of waves. They appear as alternating bright and dark fringes, with the spacing of the fringes depending on the wavelength of the light. Example experiments that produce moire fringes include the Young double-slit experiment with electrons and the observation of thin film interference.