Diffraction
14 articles on diffraction, sorted newest first.
Diffraction Grating Spectrometer Guide: 5 Easy Facts & Uses
A diffraction grating spectrometer is an instrument that splits light into its component wavelengths to reveal what substances are made of. It works by passing light through a narrow entrance slit, collimating it into a parallel beam, diffracting it off a grating, and projecting the separated wavelengths onto a detector. The grating is the key component — its groove density and blaze angle determine how finely the light is spread. Spectrometers are used in chemistry to identify elements, in astronomy to analyse starlight, and in gemology to distinguish natural from synthetic diamonds. Here is how a diffraction grating spectrometer works, the main types, and 5 key uses.
Diffraction of Sound: 5 Key Ways Sound Bends Around Corners
Diffraction of sound waves is why you hear someone talking in the next room before you see them, why bass from a subwoofer fills the whole house, and why thunder rumbles from miles away. Sound diffracts because its wavelengths are comparable to everyday objects: low bass notes have wavelengths of several metres, while high treble notes are centimetres. The longer the wavelength relative to the obstacle, the more the sound bends. Here is how diffraction works for sound, why frequency matters, and how acousticians use it to design concert halls and noise barriers.
Diffraction of Water Waves: Ripple Tank Demonstration Guide
Diffraction of water waves is the most visual way to understand how all waves bend around obstacles. A ripple tank — a shallow tray of water with a vibrating dipper — turns invisible wave physics into shadows you can see projected on a screen. Water waves diffract strongly because their wavelengths (centimetres to metres) match the size of everyday obstacles and openings. Here is how a ripple tank works, 3 essential demonstrations you can run, and what they teach about diffraction.
Diffraction Spikes Guide: 5 Best Sharpness & f-Stop Secrets
Diffraction spikes are the star-shaped rays that radiate from bright points of light in a photograph — street lamps at night, the sun through trees, or stars in an astrophotograph. They happen when light diffracts around the edges of your camera's aperture blades or a telescope's support struts. The number of spikes depends on your aperture blade count: even-numbered blades produce the same number of spikes, odd-numbered blades produce twice the number. Diffraction also softens your images at small apertures (high f-numbers) because the Airy disc — the smallest point your lens can resolve — grows larger than your sensor's pixels. Here is what diffraction spikes are, why they matter for sharpness, and 5 ways to manage them.
Diffractive Optical Elements (DOEs): Uses, Types & Applications
Diffractive optics is the technology of using micro-structured surfaces — etched or replicated patterns with features as small as a few hundred nanometres — to control light through diffraction rather than refraction or reflection. A diffractive optical element (DOE) splits a single laser beam into an array of beams, shapes a circular spot into a square one, or focuses light using a flat surface instead of a curved lens. DOEs are compact, lightweight, and can perform optical functions that conventional lenses and mirrors cannot. Here is how diffractive optics works, the main types of DOE, and 5 real-world applications.
Electron & Neutron Diffraction: How Matter Waves Reveal Structure
Electron diffraction is the wave-like scattering of electrons by crystalline materials, proving that matter has wave properties. When a beam of electrons is accelerated through a potential difference and directed at a thin crystal, it produces a diffraction pattern — exactly like X-rays or light. This is a direct consequence of wave-particle duality: every particle has a de Broglie wavelength λ = h/p, and when that wavelength is comparable to atomic spacings in a crystal, diffraction occurs. Here is how electron diffraction works, the experiments that proved it, and how it is used in techniques like TEM, LEED, and neutron diffraction.
Fraunhofer Diffraction vs Fresnel: 5 Essential Differences
Fraunhofer diffraction (far-field) and Fresnel diffraction (near-field) are two regimes that describe how diffraction patterns change with distance. In Fraunhofer diffraction, the source and screen are effectively at infinity, giving planar wavefronts and a stable pattern. In Fresnel diffraction, the source or screen is close to the aperture, giving curved wavefronts and a pattern that changes with distance. The Fresnel number N_F = a²/λL tells you which regime applies. Here is the difference, the maths, and when to use each.
Laser Diffraction & Particle Size Analysis: The Lab Guide
Laser diffraction measures particle sizes by analysing how a laser beam scatters off particles in suspension. Large particles scatter light at small angles; small particles scatter at large angles. By measuring the angular intensity pattern of the scattered light and applying Mie theory or the Fraunhofer approximation, a laser diffraction particle size analyser calculates the full particle size distribution — from tens of nanometres to several millimetres — in less than a minute. Here is how it works, the theory behind it, and what the results mean.
Single Slit Diffraction: 3 Essential Equations & Pattern
Single slit diffraction produces a pattern of bright and dark fringes when light passes through a narrow opening. The central maximum is twice as wide as the others and contains most of the light. The dark fringes follow a sin θ = mλ. Here is how the pattern works, how to derive the equation from Huygens principle, worked examples with real numbers, and why single-slit is different from double-slit or grating patterns.
X-Ray Diffraction (XRD) Explained: Crystals, Proteins & Machines
X-ray diffraction (XRD) is a technique that uses X-rays to determine the atomic and molecular structure of crystals. When X-rays hit a crystal, they scatter off the regularly spaced atoms and produce a characteristic diffraction pattern. By measuring the angles and intensities of the diffracted beams, scientists can calculate the positions of atoms in the crystal — revealing the 3D structure of materials, proteins, and even DNA. Here is how XRD works, what Bragg's law means, the machines that do it, and 5 applications you should know.
Diffraction of a Wave: How Waves Bend Around Obstacles (Guide)
Diffraction of a wave is the bending and spreading that happens when a wave meets an obstacle or passes through an opening. Water waves spread through a harbour mouth. Sound waves bend around a doorframe. Light waves spread through a narrow slit. All waves diffract, but the amount depends on one thing: the size of the obstacle relative to the wavelength. Here is how diffraction works for water waves, sound waves, and light waves — with the Huygens principle and real examples.
Diffraction Examples: 15 Surprising Everyday Phenomena (with Pictures)
Diffraction is the bending and spreading of waves around obstacles or through openings — and you see it every day. The rainbow pattern on a CD, the soft edge of a shadow, the halo around the Moon, the reason you hear someone talking in the next room before you turn the corner: all are diffraction. Light, sound, and water waves all do it, just on different scales. Here are 15 surprising diffraction examples you have seen without realising it, with pictures and explanations.