Specular reflection
A smooth surface sends a ray into a specific reflected direction.
Open this demonstrationICUX-005 · Atlas & knowledge layer · interactive companion
Color, Light and Perception Lab
Sixteen grounded demonstrations connect ray optics, wave behavior, colorimetry and visual perception. Change an illustrative screen light source, inspect what the physical explanation actually claims, then compare it with what an ordinary browser can and cannot reproduce.
16 grounded demonstrationsOriginal explanatory vectorsReproducible JSON + deep linksNot a calibrated display or clinical test
Physical explanation stays separate.
Each demonstration names its light model, viewing/display assumption, color space and approximation note. A diagram can explain geometry or relationships without pretending that its pixels are measurements.
Color is never the only signal.
Angles, labels, patterns, numeric values and text repeat the essential state. Keyboard users can reach every demonstration and control; touch targets remain large enough for coarse pointers.
01 · Reflection
Specular reflection
A smooth surface sends a ray into a specific reflected direction.
Screen source HSL hue 48°, intensity cue 82%
Physical explanation
What the grounded model says
For a smooth reflecting surface, the reflected ray leaves at an angle equal to the incident angle.
- Light model
- Sources
Screen approximation
What these pixels actually do
- Display assumption
- Color space
- Approximation note
Reproducible settings
Export or share this scene
JSON export includes the stable demonstration ID, control values, current model notes and a permalink. Reopening the permalink reproduces the interactive state, subject to normal display differences.
Full catalog
16 ways light, matter, displays and perception diverge.
The cards below are static HTML, so the knowledge layer remains readable if scripts or analytics are unavailable.
Diffuse reflection
A rough surface sends reflected light into many directions.
Open this demonstrationRefraction at a boundary
A ray changes direction when it crosses between media with different refractive indices.
Open this demonstrationTotal internal reflection
Above a critical angle, a ray in a higher-index medium can reflect instead of crossing the boundary.
Open this demonstrationDispersion through a prism
Different wavelengths can refract by different amounts, separating a broadband beam into colors.
Open this demonstrationAdditive light mixing
Overlapping red, green and blue screen-emitter regions create additive mixtures.
Open this demonstrationTransmission and absorption
A filter can transmit some portions of incident light while absorbing or reflecting others.
Open this demonstrationShort-wavelength scattering
Small-particle scattering can send shorter visible wavelengths more strongly in many directions.
Open this demonstrationPolarization analyzer
Rotating an analyzer changes transmitted intensity for linearly polarized light.
Open this demonstrationThin-film interference
Reflections from two nearby interfaces can interfere and strengthen or suppress different wavelengths.
Open this demonstrationDiffraction at an aperture
A finite aperture spreads a wave and can produce structured intensity patterns.
Open this demonstrationIlluminant × reflectance
The light reaching an observer from an object depends on both the illumination and the object's spectral reflectance.
Open this demonstrationMetameric match, then mismatch
Different spectra can produce the same tristimulus match for one observer/condition, then diverge under another condition.
Open this demonstrationSimultaneous contrast
Identical center pixels can appear different when their surrounds differ.
Open this demonstrationPhotopic versus low-light sensitivity
Visual response changes with adaptation level; rods and cones contribute differently across lighting regimes.
Open this demonstrationDisplay gamut clipping
A browser can describe colors that a particular display may not reproduce exactly.
Open this demonstrationSource & provenance ledger
Evidence is linked; third-party media is not copied.
CIE standards/publications, NIH/NEI, W3C, OpenStax and MIT perception resources ground the explanations. This candidate redistributes none of their figures or article bodies.
Defines standard colorimetric observers and colour-matching functions used in colorimetry.
Open sourceAuthoritative overview of standard observers, illuminants, tristimulus values, chromaticity, colour spaces and viewing conditions.
Open sourceSupports the distinction between physical tristimulus values and viewing-condition-dependent colour appearance.
Open sourceGrounds the simultaneous-colour-contrast demonstration and its viewing-condition caveats.
Open sourceDefines browser-facing color spaces including sRGB and explains in-gamut versus out-of-gamut CSS colors.
Open sourceGrounds the basic eye/retina/photoreceptor boundary without turning this lab into a clinical vision test.
Open sourceGrounds specular and diffuse reflection behavior.
Open sourceGrounds Snell-law refraction and changes in ray direction across media.
Open sourceGrounds polarization, analyzer rotation and intensity change.
Open sourceGrounds interference and diffraction as wave phenomena.
Open sourceGrounds dispersion, total internal reflection and the scope of geometric optics.
Open sourceGrounds the distinction between pixel luminance and perceived surface lightness under inferred illumination.
Open sourceGrounds the wavelength-dependent Rayleigh scattering explanation and the blue-sky example.
Open source