Think light emitting diodes (LEDs) are just for flashlights and cell phone displays? Think again. Once relegated to humble indicator lights in electronic devices, LED lights have advanced at remarkable rates to enable an entirely new category of lighting that’s projected to reach $30 billion by 2025.

These very same sources will one day light our homes and everyday spaces. Why? Because they’re highly efficient, long lasting, environmentally friendly and inherently controllable – enabling both new and traditional applications of light. Promising future aside, LED lighting systems already illuminate famous buildings, bridges, retail shops, television studios, theatre stages, hotels, casinos, hospitals, restaurants and celebrity-filled nightclubs around the world.

First, let’s take a look at the traditional light bulb or “lamp” as it’s called by the industry.

The light in most homes is produced by incandescent sources. The bulb structure is produced when hot glass is blown into moulds and then cooled and coated with diffusing material. Placed inside the bulb is a very thin and fragile, coiled tungsten filament (.0017 inches thick). For the bulb to produce light and an electric current is passed through a conductor and the tungsten is heated to the point at which it gives off light. Unfortunately, these bulbs, like many of their relatives, are not very energy efficient; roughly 10% of the energy is used to make visible light.

The structure of the LED light is completely different than that of the light bulb. Amazingly, the LED has a simple and strong structure. The beauty of the structure is that it is designed to be versatile, allowing for assembly into many different shapes. The light-emitting semiconductor material is what determines the LED’s colour.

As indicated by its name, the LED is a diode that emits light. A diode is a device that allows current to flow in only one direction. Almost any two conductive materials will form a diode when placed in contact with each other. When electricity is passed through the diode the atoms in one material (within the semiconductor chip) are excited to a higher energy level. The atoms in that first material have too much energy and need to release that energy. The energy is then released as the atoms shed electrons to the other material within the chip. During this energy release light is created. The colour of the light from the LED is a function of the ingredients (materials) and recipes (processes) that make up the chip.