Ceramic Heat Emitters, that is. That makes them by far the cheapest per year heat source. Any typical light bulb will burn out quickly.
Pet stores sell a brand of bulbs that look black. You can't see any color or light when you operate them during the day. But at night they emit a very bright dark, dark blue. I like that color, but it is within the light that reptiles can easily see.
I have some CHE's that have lasted about 20 years so far. I'm just careful to not bump or shake them when they are hot.
You are using the black light for nighttime heating. It emits UVA if it's working right. This wavelength is just a bit shorter than the darkest violet color we can see, and is harmless. If it emits any UVC, it would be extremely dangerous for your pet. I'm not sure whether these tubes/bulbs are tested, and I don't know exactly the wavelengths they produce. Besides, that lamp heats only because it's ballast gets warm.
Infra-red bulbs give off a really bad strong dark red color. It's very ugly. I bought one once, and instantly knew I couldn't use it. Once I broke down and bought a CHE, I never had any heating "bulbs/tubes" again.