Invisible Ink Pen With Light

Write secret messages that can only be read using the UV micro light provided. The invisible ink from the pen only fluoresces under ultraviolet light, so it is easy to keep your messages top secret. Or use it as a tool to teach about ultraviolet light and fluorescence. Your students will be keen to know why messages only show-up when the UV micro light is shone on the invisible ink. Lots of light and colour science here.

Ages: 6+

What you get

2x Invisible pen, 2x UV micro light

How does it work?

Different light has different wavelengths. Ultraviolet wavelengths are short with a very high frequency. When this UV micro light, or black light, is shone on the invisible ink from the pen, the fluorescent ink lights up with a beautiful greenish-blue luminescence. Sun light and light from incandescent bulbs do not excite the fluorescent ink and it remains invisible.

Teach

• Ultraviolet light demonstrations.
• Different wavelengths of different light.
• Wavelength frequency.
• Fluorescence.
• Valence electrons.

FAQ

Invisible ink can removed from surfaces using soap and water.