Halogen Bulb and Its Parts | Poly Notes Hub

Halogen Bulb and Its Parts | Poly Notes Hub

A halogen bulb is a type of incandescent light bulb that uses halogen gas to increase light output and lifespan. It is widely used in headlights, floodlights, and home lighting systems because of its brightness and efficiency.

In this post, we’ll discuss what a halogen bulb is, its construction, and the functions of its parts in detail.

What Is a Halogen Bulb?

A halogen bulb is an advanced version of the traditional incandescent bulb. It contains a tungsten filament sealed inside a compact transparent envelope filled with a halogen gas (such as iodine or bromine).

The presence of halogen gas enables a chemical reaction known as the halogen cycle, which redeposits evaporated tungsten back onto the filament, extending its life and maintaining brightness.

Construction of a Halogen Bulb

A typical halogen bulb consists of several key parts that work together to produce light efficiently. Below are the main components and their functions:

1. Glass Envelope (Quartz Capsule)

• Made of fused silica (quartz) or high-silica glass.
• Withstands high temperatures produced by the filament.
• Prevents the escape of halogen gas and protects the inner components.

1. Tungsten Filament

• Acts as the light-emitting element.
• When electric current passes through it, the filament heats up and glows.
• Tungsten is used because of its high melting point and durability.

1. Halogen Gas (Iodine or Bromine)

• The key component that differentiates halogen bulbs from standard incandescent bulbs.
• Helps recycle evaporated tungsten back onto the filament (halogen cycle).
• Maintains consistent brightness and prevents blackening of the bulb wall.

1. Metal Lead Wires

• Provide a path for electric current from the base to the filament.
• Made of materials with good electrical conductivity and heat resistance.

For an in-depth explanation with diagram and labeled parts, visit:
👉 Halogen Bulb and Its Parts | Poly Notes Hub

The halogen bulb is an efficient and bright lighting source that continues to find applications in vehicles, studios, and home lighting. Its halogen cycle mechanism ensures longer life and better light quality than traditional incandescent bulbs.