Why is light made up of seven colors?

What is Ultraviolet Light? How can it be used in life?

The only thing you need is that visible light is made up of seven colors of light.

Generally speaking, the selection of the three primary colors can be arbitrary, as long as the three-color mix can cover as many areas of the ignition-burning color as possible.

The three primary colors of light that are commonly set at present are:

The three primary colors of optics: red, green, and blue.

Colors combined: red and green equal to yellow; Green and blue are equal to cyan; Red and blue are equal to magenta; Red and green and blue are equal to white.

The colors written here are all macros and voids, and they are 100% superimposed colors. As they are stacked in different proportions, different colors are produced.

The color of light depends on the wavelength.

Different colors of visible light at different wavelengths:

Above the frequency range of sound waves, the frequency range that can be heard by the human ear is 20Hz-20000Hz, and the sound (20000Hz 10 12Hz or more) is called ultrasound, and the sound is called infrasound.

The frequency range of visible light is 3 9 10 14 to 7 7 10 14 Hz, the frequency range of ultraviolet light is roughly 8 10 14 to 3 10 17 Hz, and the infrared wavelength range is roughly 3 10 11 to about 4 10 14 Hz.

Light waves are electromagnetic waves, and sound waves are mechanical waves. The speed of light waves (i.e., the visible brother spectrum of electromagnetic waves) is 300,000 kilometers per second, the speed of sound waves is 340 meters per second, the transmission speed of the human optic nerve is 1200 1400 meters per second, and the transmission speed of the human auditory nerve is 800 1200 meters per second.

Difference Between Sound Wave and Light Wave:

The greater difference between sound waves and light waves is that the former requires a medium, while the latter does not. The Doppler effect of sound waves is related to the mutual motion of the wave source, the medium, and the observer. Since light waves have no medium, the Doppler effect of light only involves the relative motion between the light source and the observer.

Laser wavelength:

The concept of laser wavelength:

Laser wavelength refers to the output wavelength of the laser, which is an important parameter of the laser output laser beam. The frequency of the corresponding output is called the laser frequency.

In fact, laser is also a kind of electromagnetic wave, but the wavelength of the laser is not an order of magnitude with the radio wave of the dust-free line, it is many orders of magnitude shorter than the radio wave. The wavelength unit of a laser is usually measured in nm, and lasers can be divided into two categories: visible and invisible. In general, the wavelength of visible light that can be clearly distinguished by the human eye is basically between 400 nm and 700 nm.

The law of wavelength and color of laser:

The shorter the wavelength of the laser, the bluer and violet its color will be, up to the ultraviolet rays, which are invisible to the human eye. However, the longer the wavelength, the more red its color shifts until the infrared, which is invisible to the human eye. The human eye is most sensitive to green, orange and yellow light with wavelengths between 550-570 nanometers.

Therefore, in the visible range, the wavelength can be understood as a numerical identifier of the color.

The color wavelengths of laser visible beams from short to long are: blue-violet (375nm, 405nm), blue (445nm, 488nm), green (520nm, 532nm), yellow (589nm, 577nm) and red (635nm, 650nm); Lasers in this wavelength range are often used in stage performances and medical applications.

Red, orange, yellow, green, blue, indigo, purple.

Sunlight is refracted through a prism and forms a colored band of light on the screen. The end of the light band near the top corner of the prism is red, and the end near the bottom surface is purple, forming a seven-color band of red, orange, yellow, green, blue, indigo, and violet.

If you put another prism and turn its bottom upside down, allowing the seven colors of light to pass through, it will form a beam of white light. Newton's experiments showed that white sunlight is made up of a mixture of seven colors of light.