An "nm laser" refers to a laser that emits light at a specific wavelength, measured in nanometers (nm). This wavelength determines the color of the laser light.
Here's a breakdown:
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nm stands for nanometer: A nanometer is a unit of length equal to one billionth of a meter (1 x 10-9 meters). It's used to measure the wavelength of light.
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Laser: A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation.
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Wavelength and Color: The wavelength of light directly corresponds to the color we perceive. Different wavelengths fall within different parts of the electromagnetic spectrum, which determines the color.
Common examples of laser pointers and their corresponding wavelengths include:
- Red Lasers: Typically range from 630 nm to 670 nm.
- Green Lasers: Often operate at 520 nm or 532 nm.
- Violet/Blue Lasers: Usually emit light at 405 nm or 445 nm.
Therefore, when someone refers to a "405 nm laser," for instance, they're talking about a laser that emits violet light with a wavelength of 405 nanometers. The lower the nanometer value, the closer the color is to the ultraviolet spectrum, and the higher the value, the closer to the infrared spectrum.
