Insight - How Electric Bulb works
Table of Contents:
The outer glass is attached to the lower casing with the help of a stick material. The environment inside the glass is made inert by filling with a gas like argon. This prevents oxidation of filament at such high temperatures.
There is another assembly glass assembly inside the outer glass which holds the filament, the support wires, and the contact wires. This glass assembly is also called the stem of the bulb.