Which of the following procedures best describes the use of diffractive phenomena in separating the individual components of an electromagnetic wavefront?

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11ecba2d_1317_e3a8_a3bf_e953be222a4b_MD0008_00 A diffraction grate is a diffractive array composed of numerous slits with near-zero width similar to the wavelength of incident light. Like the band patterns produced through single-slit diffraction and double-slit diffraction, dark bands that result from light passing through a diffraction grate are caused by destructive interference between light waves. Conversely, light bands are caused by constructive interference between light waves. Compared to other diffractive phenomena, the band pattern caused by grated diffraction is characterized by relatively sharp and narrow peaks (ie, thin peaks with highly variable amplitude). This band pattern occurs because constructive and destructive interference occurs not only between waves emerging from adjacent slits (eg, double-slit diffraction) but also between waves emerging from slits separated from each other by other slits. Light bands (regions of maximum light intensity) from the diffraction grating occur when diffracted light waves pass through the slits at angles (θ) that are a function of the distance separating each slit (d) and an integer multiple (m = ±1, ±2, ±3…) of the wavelength: 11ecba2d_1318_0ab9_a3bf_2d504061eaad_MD0008_00 The sharp, narrow peaks of the band pattern produced by a diffraction grating are useful in analyzing the properties of the light that enters the slit. For example, long-wavelength light diffracts more than short-wavelength light. Consequently, transmitting polychromatic light composed of light waves with different wavelengths (eg, white light) through a diffraction grate will produce a series of multicolored arrays (eg, rainbows) that enables an analysis of wavefront composition. (Choices A and B) Compared to grated diffraction, the band patterns produced by single- and double-slit diffraction are relatively diffuse. Therefore, single- and double-slit diffractions are not helpful in analyzing the individual components of light wavefronts. (Choice D) In contrast to polychromatic white light, monochromatic light is composed of only one color (ie, one wavelength). Consequently, the wavelength of monochromatic light can be detected without the use of diffraction. Educational objective: Diffraction grating refers to passage of light through an array consisting of numerous slits. Diffraction grating may be used to determine the components of polychromatic (eg, white) light and other mixed electromagnetic wavefronts.

Which of the Following Procedures Best Describes the Use of Diffractive