Metal Halide "Coated"

[ElectDesigner]

When referring to metal halide lamps, the term coating is often used, I just want to know what exactly they are referring to by "coated", are they refering to:
1. Coating on the outside of the lamp, to prevent shattering? Or
2. Coating on the arc tube to keep the right temp.

Or something else?

 

[Stevareno]

I would assume it means a coating on the inside of the outer globe, much like an incandescent bulb.

Clear


Coated

 

[Hv&Lv]

When referring to metal halide lamps, the term coating is often used, I just want to know what exactly they are referring to by "coated", are they refering to:
1. Coating on the outside of the lamp, to prevent shattering?

Normally the coated ones we buy are the phosphor coating on the inside of the outer shield.
The shattershield coatings are normally special order in my experience.

 

[weressl]

When referring to metal halide lamps, the term coating is often used, I just want to know what exactly they are referring to by "coated", are they refering to:
1. Coating on the outside of the lamp, to prevent shattering? Or
2. Coating on the arc tube to keep the right temp.

Or something else?

The coating is on the inside of the bulb.

1. to diffuse the light
2. If it is an active - phosphorous - coating, it changes the lights color properties.
3. UV filtering

 

[ElectDesigner]

Thanks guys.

 

[Andrew Hui]

coat picture

coat picture


This is a coated fixture, you can see that coat on the outer frame to improve the lumen effect. For HML, coat also means the inside white powder like a flourescent.