itsevalaiseva

Itsevalaiseva is a Finnish term that translates to "self-luminous" or "phosphorescent" in English. It describes a material or object that emits light without external stimulation, such as heat or electricity, after being exposed to a light source. This phenomenon is a form of luminescence, specifically phosphorescence, where energy is absorbed and then slowly re-emitted as light over a period of time.

The effect is typically achieved through the use of phosphorescent pigments. These pigments contain compounds, often based on rare earth elements like strontium aluminate, that can store energy from ambient light. When the external light source is removed, the stored energy is gradually released, causing the material to glow. The intensity and duration of the glow depend on the type of pigment used, the amount of light absorbed, and the surrounding conditions.

Common applications for itsevalaiseva materials include safety signage, emergency exit markers, watches, toys, and decorative items. They are valued for their ability to provide visibility in low-light or blackout conditions without requiring batteries or a power supply. The glow can last for several hours, gradually fading as the stored energy is depleted. The term emphasizes the inherent light-emitting property of the material itself.