Difference Between Ceramic & Quartz Metal Halide Lamp

Metal halide lamps use a gas to produce light directly from their arc tubes.

Ceramic and quartz versions of metal halide lamps are both available for commercial and residential uses. Metal halide lamps are common where bright lamps are needed to illuminate landscaping or construction projects. Some types of metal halide lamps are used to grow plants indoors. In many ways, metal halide science is similar to fluorescent lights, but the light quality and brightness is different. Ceramic lights are newer metal halide lights designed to be more efficient than quartz.

Quartz

Quart metal halide lamps are the traditional versions. They use arc tubes that are made of quartz. On either side of the tube are electrodes that allow the electricity to arc through the tube, just like in a fluorescent light. The tube is filled with a gas that becomes electrically charged and released light wavelengths when the electricity passes through it.

Ceramic

Ceramic metal halide lamps have arc tubes too, but they tend to forego the tube shape for a more box or sphere-like design where the electrodes are positioned closer to each other and the shell is made out of ceramic materials instead of quartz. The gas used inside is also slightly changed and usually contains a greater number of filler materials.

Durability

The primary different between quartz and ceramic bulbs is that ceramic versions are hardier, able to withstand higher temperatures than the quartz versions. This allows the gas inside to reach higher temperatures and the gas composition to be altered slightly. Ceramic also tends to be less easily corroded, so manufacturers do not need to worry as much about the gas eating away at the bulb over time.

Efficacy

With a higher proportion of filler in the metal halide gas, light is produced more easily with less energy, saving electricity. The light brightness also tends to be more stable from lamp to lamp, allowing for easier set-up when using metal halide lamps for landscaping. The ceramic versions are also praised for their smoother, more consistent coloring.

Ballasts

Ballasts manage the electrical current that flows through the metal halide tube. Both quartz and ceramic tubes use the same ballasts, which allows for easier ballast replacement. However, ceramic versions are more often available at lower wattages than quartz versions.

References

• RPI: What is the difference between quartz and ceramic arc tubes?
• Osram: Metal halide lamps with ceramic technology
• Acuity Brands Lighting: GUIDE for Selecting EISA-Compliant Alternatives to 175W Probe Start Metal Halide Products