Slide: Cut through the Single-Field Condensing Lens and Objective with Polschuh Lens and Specimen Gate
The Photoelectric Effect
When light shines on a metal, electrons are emitted from the metal surface. The measured voltage - and so the energy of the electrons - only depends on the color of the light. Einstein's explanation: Light delivers energy in quanta - blue light quanta have more energy than red light. However, not even Einstein himself claims that light simply consists of particles since the wave-like characteristics of light are too well established.