What is the wavelength of a red laser?

Wavelength of a Red Laser

Lasers emit light at specific wavelengths, which correspond to different colors when they fall within the visible spectrum of light. The color of a laser is determined by its wavelength, which is measured in nanometers (nm). The wavelength of a red laser typically falls within a certain range of the visible spectrum.

Typical Wavelength Range for Red Lasers

Red lasers commonly have wavelengths that extend from about 620 nm to 750 nm. Within this range, the human eye perceives light as red. The specific wavelength used can vary depending on the application and type of red laser.

Common Types of Red Lasers

• Helium-Neon Lasers: These often have a wavelength of around 632.8 nm and are known for their excellent coherence properties.
• Diode Lasers: These can emit at various wavelengths within the red part of the spectrum, typically starting at 635 nm going up to around 690 nm or higher.

Applications of Red Lasers

Red lasers are used in a variety of applications due to their visibility and the technology available to produce them. Common applications include barcode scanners, laser pointers, surveying equipment, and in some cases, medical procedures.

Laser Emission Principle

Lasers operate on the principle of stimulated emission of radiation. A medium (gas, liquid, or solid) is excited to a higher energy state. When the excited electrons in the medium return to a lower energy state, they emit photons which are all coherent, meaning they are at the same wavelength and phase. The specific wavelength of the light emitted primarily depends on the medium used and the design of the laser.

Conclusion

The wavelength of a red laser falls within the red region of the visible spectrum, commonly between 620 nm and 750 nm. This specific range allows for a variety of practical applications based on the properties of red light.