Lähdevalaisimet

Lähdevalaisimet, commonly translated as source luminaires or light sources, refer to the components within a lighting fixture that actually produce light. This is a fundamental concept in lighting design and electrical engineering. The type of source luminaire used significantly impacts the fixture's performance, energy efficiency, color rendering, and overall aesthetic.

Historically, incandescent bulbs were the primary source luminaire. These work by heating a filament until it glows. While offering good color rendering, they are very inefficient, converting most of their energy into heat rather than light. Fluorescent lamps became a popular alternative, offering much higher efficiency. These tubes contain a gas that, when excited by an electric current, emits ultraviolet light, which then strikes a phosphor coating on the inside of the tube, causing it to emit visible light.

Modern lighting predominantly relies on Light Emitting Diodes (LEDs) as source luminaires. LEDs are semiconductor devices that emit light when an electric current passes through them. They are highly energy-efficient, have a very long lifespan, and offer excellent control over color temperature and brightness. Other source luminaires include high-intensity discharge (HID) lamps like metal halide and high-pressure sodium, often used in streetlights and industrial applications due to their high lumen output. The choice of source luminaire is a critical design decision based on the intended application, desired light quality, and energy consumption targets.