A gas-catalytic infrared oven is switched on, a coated product is conveyed through and leaves the oven with the powder coating perfectly cured.
Nevertheless, the oven appears black inside. Shouldn't it be lit up? Are infrared emitters not usually orange-red?
No, because infrared radiation is a thermal radiation that is invisible to us. The radiation from an infrared emitter will only be visible to us if it emits some visible light in addition to the radiation. Radiation from short-wave emitters shines brighter than long-wave radiation.
However, gas-catalytic infrared emitters usually emit medium to long-wave radiation, usually with a spectrum that is far away from the visible range. A gas-catalytic heating panel therefore looks dark; however, the radiation can be felt as heat.
A thermal camera can visualize the heat radiation. Our picture shows a thermo camera taking pictures of the gas-catalytic oven while the product was being cured. And here you can see it, the invisible infrared radiation in radiant colors.