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Page 8 of 13 — articles on the physics of light, sorted newest first.
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.
What Is a Diffraction Grating? How It Works, Equation & Types
A diffraction grating is an optical component with a periodic structure that splits light into its constituent wavelengths. Think of it as a supercharged prism. Where a prism bends different colours by different amounts, a diffraction grating separates colours by constructive and destructive interference from thousands of closely spaced slits or grooves. The result is a clean, evenly spaced rainbow spectrum. Gratings are used in spectrometers to identify chemical elements, in CD players to read data, and in telescopes to study stars.
What Is Diffraction? Simple Definition, 7+ Examples & Diagram
Diffraction is the bending and spreading of waves around obstacles or through openings. It happens when a wave meets an object or aperture roughly the same size as its wavelength — the closer the match, the more the wave spreads. Sound diffracts around doorways (which is why you hear someone in the next room). Light diffracts through a narrow slit (which is why a laser beam spreads into a pattern of bright and dark bands). The effect is strongest when the obstacle or opening is about the same size as the wavelength. Here is what diffraction is, how it works, and 7 everyday examples.
Converging vs Diverging Lens: What's the Difference?
A converging lens is convex and bends light inward to meet at a focal point. A diverging lens is concave and spreads light outward. A converging lens can form real or virtual images; a diverging lens always forms virtual, diminished images. Converging lenses are used in cameras, telescopes, and magnifying glasses. Diverging lenses correct myopia, widen peephole views, and expand laser beams.
Lens vs Mirror: 5 Key Differences & Simple Comparison Guide
A lens refracts light through a transparent material; a mirror reflects light off a coated surface. A convex lens converges light like a concave mirror, and a concave lens diverges light like a convex mirror. Here are the 5 key differences between lenses and mirrors, how they pair up, and when to use each.
Convex Lens in Telescopes & Other Real-World Uses
A convex lens in a telescope gathers light from distant objects and brings it to a focus. Convex lenses are also used in magnifying glasses, cameras, microscopes, eyeglasses for farsightedness, and projectors. Here is how each application works and the optics behind it.
Convex Lens Ray Diagram: How to Draw All 6 Object Positions
A convex lens ray diagram uses three principal rays to find the image: the parallel ray, the focal ray, and the centre ray. The image type, size, and orientation depend on the object's distance from the lens. Here is a step-by-step method for all 6 positions — from infinity to between the lens and the focal point.
How Does a Lens Work? Light, Focus & the Lensmaker's Equation
A lens works by bending (refracting) light as it passes through its curved surfaces. A convex lens converges parallel rays to a focal point; a concave lens diverges them. The lensmaker's equation relates the shape and material to the focal length. Here is how lenses work from first principles, with simple worked examples.
Simple Guide: Is a Magnifying Glass Convex or Concave?
A magnifying glass uses a convex lens — thicker in the middle, thinner at the edges. This shape converges light to a focal point, and when the object sits inside the focal length, the lens produces a magnified, upright, virtual image. Here is why only a convex lens can do this and why a concave lens cannot.
How to Draw Ray Diagrams for Mirrors (Step-by-Step Guide)
A ray diagram traces the path of light from an object to a mirror to determine where an image forms. Drawing a concave mirror ray diagram takes just four steps: set up the mirror and axis, draw two incident rays, reflect them using the rules, and mark where they meet. This guide covers those steps for every object position for both concave and convex mirrors, plus the common mistakes that trip students up.
Concave Mirror: Complete Guide, Working, 6 Image Cases & Uses
A concave mirror is a curved mirror where the reflecting surface curves inward like a cave. It converges parallel light rays to a single focal point in front of the mirror. This ability to focus light makes it essential in telescopes, headlights, shaving mirrors, dental mirrors, and solar furnaces. Here is everything you need to know about concave mirrors, from ray diagrams to image formation to the mirror formula.
Concave vs Convex Mirror: Differences, Uses & Diagrams (Comparison)
Concave mirrors curve inward and converge light to a focus, producing real or virtual images. Convex mirrors curve outward and diverge light, always producing virtual, upright, diminished images with a wider field of view. Here are the key differences between the two types of spherical mirrors, with comparison tables for image formation, ray diagrams, applications, and a simple trick to remember which is which.