200 Years of Pioneering Spirit: How Otto Lehmann Laid the Foundation for Modern Displays

Otto Lehmann conducted research on “living crystals” at Karlsruhe Institute of Technology (KIT) – and laid the foundation for modern displays. When Lehmann assumed the chair of physics at what was then the Karlsruhe Polytechnic in 1889, no one could have imagined that his research would one day end up in almost every pocket. The successor to Heinrich Hertz was an inventor with vision – and a fascination for the invisible.

An Idea Ahead of Its Time

Using a microscope he had developed himself, which featured its own light source and a heatable sample stage, Lehmann observed the behavior of chemical substances as they melted and solidified. In doing so, he discovered something entirely new: states of matter that behaved neither like liquids nor like solid crystals – but like both at once.
Lehmann called them “apparently living crystals.” Today, we know them as liquid crystals – the basis for LCDs (liquid crystal displays) used in flat screens, tablets, and smartphones. In 1904, Lehmann published his groundbreaking findings in the book Flüssige Kristalle (Liquid Crystals). But his contemporaries dismissed him as an eccentric. A colleague in Karlsruhe sneered that Lehmann was “horribly one-sided in his focus on liquid crystals.” The scientific community ignored him – and his discovery was forgotten for decades.

From Outsider to Pioneer

It wasn’t until the 1970s, when the first LCDs were developed, that people remembered the pioneer from Karlsruhe. Today, every liquid crystal laboratory uses a microscope based on Lehmann’s design, and his name has long since been rehabilitated – as the founder of a technology that makes our digital world visible.

mex, July 30, 2025