GLOW IN THE DARK: HOW DOES IT WORK?

Did you know that you need to charge things that glow in the dark? I don’t mean to say that you need to plug them in but they do need light to charge up the active ingredients inside so that they can slowly release that energy as the glow we know and love.

In short, you need light to create light!

Things that glow in the dark work by absorbing short wavelength light (like blacklight or direct sunlight) and then slowly releasing it as a glow after the light source is gone. 

The wavelength of light used to charge your glow-in-the-dark or phosphorescent objects greatly affects how long its takes to charge and how bright it can glow. The list below can help give you an idea of what I mean.

• 3-4 mins of ultraviolet (black) light

• 7-8 mins of direct sunlight

• 21-23 mins of fluorescent light (strip lighting or energy-saving bulbs)

• 24-26 mins of incandescent light (standard filament bulbs)

There are also two different agents used in glow-in-the-dark things phosphors zinc sulphide which has been around for a longer time and the newer strontium aluminate. Strontium aluminate glows brighter for longer making it ideal to create the ultimate glow-in-the-dark object.

You can also see the difference within these glow-in-the-dark mushroom shelves we make. While I know with certainty the blue, orange, red and yellow colors are made with strontium aluminate and glow brightly for a long time it is uncertain what some of my other filament colors use as they are not as bright or as long-lived.

My partner and I made a chart to help you understand the brightness and duration of the glow of our colors - at least subjectively and comparatively and give it a rank out of 5.