A glow lamp, also known as a neon lamp or indicator lamp, is a small electrical device used as a visual indicator or signal. It typically consists of a glass envelope filled with gas, such as neon, argon, or a mixture of gases, at low pressure. The inside of the envelope is coated with a phosphor material that emits light when ionized by an electric current passing through it.
When a voltage is applied across its electrodes, a glow discharge is established within the gas-filled envelope. The discharge creates a distinctive glow or colored light, depending on the gas used and the composition of the phosphor coating. This emitted light is generally bright and has a characteristic hue that can range from red, orange, yellow, green, blue, to white.
Glow lamps are commonly used as indicators on various devices and equipment to signal power on/off status, activity, or warning messages. They are frequently found in household appliances, electronic devices, automotive instrumentation, industrial control panels, and signage.
One of the main advantages of glow lamps is their longevity, as they have a relatively long operating life and can last for thousands of hours. Moreover, they are energy-efficient, requiring low power to operate. However, with the advancement in technology, glow lamps have largely been replaced by more modern and efficient alternatives, such as light-emitting diodes (LEDs), which offer greater flexibility, reduced energy consumption, and longer lifespans.
