The color of a neon tube can vary depending on the gas or gases used within it. Here's a detailed explanation:

Pure Neon Gas

• Color: When pure neon gas is used in a vacuum tube and an electric current is applied, it glows a bright red-orange color.
• Source: This information is based on the scientific properties of neon gas, which is widely documented and accepted in the scientific community.

Colored Neon Signs

• Non-red-orange Colors: If a neon sign displays a color other than red-orange, it is because other gases have been added to the neon. These gases, such as argon, krypton, helium, xenon, or even small amounts of mercury, can alter the color of the light emitted.
  • Argon: When lit, argon gas produces a lavender color. With a tiny drop of mercury, it can produce ultraviolet light.
  • Helium: Produces an orange-white color.
  • Krypton: Emits a greenish-gray color.
  • Mercury Vapor: Produces a pale blue light.
  • Xenon: Produces a blue-gray color.
• Source: These details are derived from scientific experiments and observations on the properties of different gases when excited by an electric current in a vacuum tube.

LED-based Neon Tubes

• Color Variety: Modern LED-based "neon" tubes, often marketed as LED neon flex strips or LED neon rope lights, offer a wide range of colors including but not limited to red, green, blue, yellow, purple, warm white, RGB (Red-Green-Blue), and RGBW (Red-Green-Blue-White).
• Advantages: LED neon tubes are energy-efficient, long-lasting, and can be easily controlled to create dynamic lighting effects.
• Source: This information is based on the product specifications and descriptions provided by manufacturers and suppliers of LED neon tubes.

Conclusion

The color of a neon tube can be red-orange when pure neon gas is used, or it can be any other color depending on the additional gases included in the tube. Additionally, LED-based neon tubes offer a vast array of colors and lighting effects, making them versatile and popular for various applications.