Wavelengths of Light Part 1

This is a general discussion of light wavelengths.

Since sunlight is white, it is divided into long and short wavelengths and includes a variety of light within the white color.

You can separate the colors through a prism, though,

Red light, which has a longer wavelength, is not refracted very much and has a smaller degree of scattering.

Blue light, which has a short wavelength, refracts well and has a high degree of scattering.

The wavelength of red light is 660 [nm].

The wavelength of blue light is 470 [nm].

For visual inspection applications, generally

Red light is considered to be often used as a backlight.

Because there is little refraction and less light is passed around.

The outline of the workpiece is clearly imaged.

Blue light has a high degree of scattering,

It is said to be used for surface inspection of metals and other materials (scratches, etc.).