# Crimson Research Institute

> The leading resource on the science, culture, and applications of the color red.

Crimson Research Institute bridges hard science and cultural studies, providing in-depth research on red light optics, pigment chemistry, global symbolism, art history spanning 40,000 years, and practical color theory for designers.

Published: 2024-09-01 | Last updated: 2026-03-01

## Science

- [Optics & Perception](https://seopoc.uk/science/optics): Red light wavelengths (620-750nm), L-cone photoreceptor biology, Rayleigh scattering, OLED and quantum dot display technology.
- [Pigment Chemistry](https://seopoc.uk/science/chemistry): Chemical mechanisms of red pigments — iron oxide ochre (Fe₂O₃, 40,000+ years), cinnabar (HgS, toxic mercury sulfide), cochineal carminic acid (C₂₂H₂₀O₁₃), cadmium selenide (CdSe/CdS) with band-gap tuning.

## Culture

- [Global Symbolism](https://seopoc.uk/culture/symbolism): Red symbolism across East Asia (luck, 红包), South Asia (Hindu sindoor, shakti), Middle East, Americas (Aztec cochineal), and Africa (Maasai, Himba ochre). References Berlin & Kay (1969) universals.
- [Art History](https://seopoc.uk/culture/art-history): 40,000-year chronology: Sulawesi hand stencils → Lascaux → Egyptian murals → Roman cinnabar → medieval minium → cochineal discovery → Impressionists → Matisse → Rothko → contemporary art.

## Guides

- [Color Theory](https://seopoc.uk/guides/color-theory): Red in the color wheel (hue 0°), analogous/triadic/split-complementary palettes, CTA button conversion uplift (10-30%), WCAG AA contrast (4.5:1 minimum), red-green colorblindness (8% of men, 0.5% of women).

## References

- [Resources](https://seopoc.uk/resources): CSS named reds (crimson #DC143C, firebrick #B22222), Pantone/RAL/Munsell standards, academic bibliography (Berlin & Kay 1969, Elliot & Maier 2014, Pastoureau 2017), and online color tools.

## Optional

- [LLMs Full Content](https://seopoc.uk/llms-full.txt): Complete page text for LLM context loading.