Size of the source: A smaller source produces better-defined diffraction patterns compared to a larger source
Slide 19: Applications of diffraction patterns
Diffraction patterns are used in various scientific and technological applications, including:
X-ray crystallography to determine atomic structures
Optical microscopy to enhance resolution
Spectroscopy to analyze the properties of materials
Slide 20: Conclusion
Diffraction patterns occur when waves pass through narrow slits or circular apertures
Single-slit diffraction produces a central bright fringe surrounded by alternating dark and bright fringes
Circular aperture diffraction produces a central bright spot surrounded by alternating dark and bright rings
Various factors such as wavelength, size of the aperture or slit, distance, and source size affect the diffraction patterns
Slide 21: Diffraction grating
A diffraction grating is an optical device that contains a large number of equally spaced slits or rulings
It is used to separate light into its component wavelengths
The spacing between the slits determines the angular separation of the diffracted wavelengths
The formula for the angular separation is given by: sinθ = mλ / d, where d is the spacing between the slits and m is the order of the maximum
Slide 22: Diffraction and interference
Diffraction and interference are closely related phenomena
Diffraction is the bending and spreading of waves around obstacles or through openings
Interference is the interaction and superposition of waves, resulting in constructive or destructive interference
Both phenomena can be observed in diffraction patterns
Slide 23: Diffraction in everyday life
Diffraction is not limited to the study of light waves
It can also be observed in everyday life, such as:
The bending of sound waves around obstacles
The spreading of water waves after passing through a small opening
The interference patterns formed by radio waves
Slide 24: Diffraction in photography
Diffraction affects the quality and sharpness of images in photography
As light passes through a small aperture in a camera lens, it diffracts, leading to a decrease in image sharpness
This is why larger apertures (smaller f-numbers) are used to capture sharper images with less diffraction
Slide 25: Diffraction-limited resolution
The diffraction-limited resolution is the maximum resolution that can be achieved for an optical system
It is determined by the wavelength of light and the size of the aperture
The formula for the diffraction-limited resolution is given by: θ ≈ 1.22λ / D, where θ is the angular resolution, λ is the wavelength, and D is the diameter of the aperture
Slide 26: Rayleigh criterion
The Rayleigh criterion is used to determine the minimum resolvable detail in an optical system
According to the criterion, two point sources are just resolvable if the maximum of the central diffraction pattern of one source coincides with the first minimum of the diffraction pattern of the other source
The formula for the Rayleigh criterion is given by: θ ≈ 1.22λ / D, where θ is the angular resolution, λ is the wavelength, and D is the diameter of the aperture
Slide 27: Applications of diffraction
Diffraction has numerous applications in various fields, including:
X-ray diffraction for studying crystal structures
Spectrophotometry for analyzing the chemical composition of substances
Holography for creating three-dimensional images
Optical storage devices such as CDs and DVDs
Slide 28: Diffraction in astronomy
Diffraction plays a crucial role in astronomy, allowing scientists to study distant celestial objects and phenomena
Astronomers use various diffraction-based techniques, such as:
Spectroscopy to analyze the composition and temperature of stars
Interferometry to enhance resolution and study distant objects
Coronagraphy to observe the faint structures around stars
Slide 29: Diffraction and wave-particle duality
Diffraction and interference phenomena provide evidence for the wave nature of particles such as electrons and photons
The diffraction of electrons and photons, observed in experiments, supports the concept of wave-particle duality
The diffraction patterns obtained are consistent with the wave nature of particles
Slide 30: Summary
Diffraction is the bending and spreading of waves around obstacles or through openings
Diffraction patterns can be observed when waves pass through narrow slits or circular apertures
The properties of the diffraction pattern depend on factors such as wavelength, size of the aperture or slit, and distance between the source and the screen
Diffraction has applications in various fields, including optics, spectroscopy, astronomy, and particle physics
Diffraction Patterns Due to a ‘Single-Slit’ and a ‘Circular Aperture - Title Sequence Definition of diffraction Diffraction patterns Single-slit diffraction Circular aperture diffraction Factors affecting diffraction patterns