Diffraction

Front

Diffraction Noun

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[dih-frak-shun]

Back

Diffraction

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The spreading out of waves from a straight-line path as they pass through a narrow opening or around an edge.

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Example: Sound waves from Jack bend, or diffract, as they pass through the doorway, allowing Jill to hear him even without a direct line of sight.

Front

Huygens' Principle Noun

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[hoy-genz prin-suh-pul]

Back

Huygens' Principle

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The principle that every point on a wavefront can be considered a source of tiny secondary wavelets that spread forward.

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Example: This diagram shows how a wave moves forward: each point on a wavefront acts as a source for a new, smaller wave, and the next wavefront is formed by combining them.

Front

Diffraction Pattern Noun

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[dih-frak-shun pat-ern]

Back

Diffraction Pattern

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The pattern of bright and dark bands produced by the interference of waves after passing through an aperture or around an obstacle.

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Example: This image shows that when a wave passes through a narrow gap, it spreads out more (large diffraction effect) than when it passes through a wide gap.

Front

Coherent Light Noun

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[koh-heer-ent lite]

Back

Coherent Light

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Light in which the waves have a constant and predictable phase relationship, allowing for stable interference and diffraction patterns.

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Example: This diagram shows how a single light source passing through two narrow slits creates two new sources of light waves whose crests and troughs are perfectly aligned, making them coherent.

Front

Monochromatic Light Noun

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[mon-oh-kroh-mat-ik lite]

Back

Monochromatic Light

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Light that is composed of a single wavelength or a very narrow range of wavelengths, appearing as a single color.

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Example: This diagram shows that monochromatic light, like from a laser, consists of light waves of a single frequency, unlike sunlight which has many frequencies.

Front

Diffraction Grating Noun

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[dih-frak-shun gray-ting]

Back

Diffraction Grating

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A device with many small, equally spaced slits or lines that diffracts light to form a pattern for wavelength analysis.

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Example: When a beam of white light hits a diffraction grating, the light waves bend and spread out, separating into their individual colors to form a spectrum.

Front

Transmission Grating Noun

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[trans-mish-un gray-ting]

Back

Transmission Grating

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A diffraction grating on a transparent material where light passes through spaces between lines, which act as multiple parallel slits.

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Example: When light passes through a transmission grating, it splits into multiple beams, creating a pattern of bright spots called diffraction orders on a screen.

Front

Reflection Grating Noun

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[ri-flek-shun gray-ting]

Back

Reflection Grating

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A diffraction grating with fine lines on a reflective surface, which reflects light to form a diffraction pattern.

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Example: When white light hits a reflection grating, the surface reflects and splits the light into its different colors, similar to a rainbow.

Front

Grating Spectroscope Noun

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[gray-ting spek-truh-skohp]

Back

Grating Spectroscope

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An instrument that uses a diffraction grating to separate light into its constituent wavelengths for precise measurement and analysis.

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Example: A diffraction grating splits a single beam of white light into its different colors, separating them into a spectrum, which is the basic principle of a spectroscope.

Front

Aperture Noun

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[ap-er-cher]

Back

Aperture

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A circular opening or hole, such as a lens or pupil, through which light passes and is subsequently diffracted.

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Example: This diagram illustrates 'depth of field' in photography, showing how a camera can focus on nearby objects (flowers) while distant objects (bear, mountains) appear blurry.