Visible light is the portion of the electromagnetic spectrum that is visible to the human eye, ranging from red to violet wavelengths between 380-740 nanometers. Ultraviolet light has shorter wavelengths than visible light and is invisible but can be detected by some insects. There are three types of UV light - UV-A between 400-315 nm, UV-B between 315-280 nm, and UV-C between 280-100 nm.
3. Visible light
•Visible to the human eye.
•Also known as the “optical spectrum of light.”
•The only part of the electromagnetic spectrum that we can see.
•The wavelength of the light determines the perceived color.
4. The Visible Light Spectrum
Color Wavelength (nm)
Red 625-740
Orange 590-625
Yellow 565-590
Green 520-565
Cyan 500-520
Blue 435-500
Violet 380-435
5. Ultraviolet light (UV Light)
• Invisible rays that are parts of the energy that comes from the sun.
• Means “beyond violet”
• Have shorter wavelengths than visible light
• Some insects can see them.
• Called “oxidizing rays” by johann walhelm ritter, the one who discovered UV Light.
Johann Wilhelm
ritter
6. Three types of UV Light
1. UV-a (400nm-315nm)
2. UV-b (315nm-280nm
3. UV-C (280-100nm)
