Introduction to laser wavelength, laser power and laser brightness
There are many technical parameters describing a laser, but for the demonstration laser, the most important and the most heard are the three terms of laser wavelength, laser power and laser brightness. Many people don’t understand the relationship between these three, so that when buying laser lights, they are often misled intentionally or unintentionally by manufacturers and suppliers who don’t understand laser. There is a big difference. Below, the brief answer is as follows:
A. What is the concept of laser wavelength?
Answer: Anyone who has studied electronics knows the wavelength of radio, or a more professional one is the wavelength of electromagnetic waves. In fact, laser is also an electromagnetic wave, but the wavelength of laser is not in the same order of magnitude as radio waves, it is many orders of magnitude shorter than radio waves. The wavelength unit of the laser is usually measured in nm (1/1000000000 meters), and the laser can be divided into two categories: visible laser and invisible laser.
In the visible laser used for performances, lasers of many colors can be separated according to the different wavelengths. The wavelength of visible laser that can be clearly distinguished by the human eye is basically between 400nm and 700nm. The shorter the wavelength of the laser, the more bluish-violet its color will be invisible to the human eye until the ultraviolet; and the longer the wavelength, the more its color will be red, until the infrared, which is invisible to the human eye. , Orange, and yellow light are the most sensitive. Therefore, in the visible light range, wavelength can be understood as a digital identification of color.
B. How is laser power defined?
Answer: Like electric energy, the light emitted by a laser is also an energy source, but it appears in the form of light. Therefore, the output power of a laser is the same as the output power of a generator in a power plant. It is a physical dimension measuring the output energy per unit time. The unit of measurement used is the same as electric power, which is also W (watts) or milliwatts (mW).
In order to understand the concept of 'laser powerJust a 1W laser. In fact, the DPSS laser commonly used in laser shows is a typical electro-optical converter, but its conversion efficiency is less than 100%, which is only a few to tens of percent.
C. What is the relationship between laser brightness and laser power and wavelength?
Answer: Laser brightness is the comprehensive subjective perception or description of laser wavelength and laser power by the human eye. There is a wavelength meter to measure the laser wavelength, and a power meter to measure the laser power. There are objective standards for measuring these two physical quantities, and they are calibrated general-purpose instruments and equipment. The measurement of laser brightness can only be seen with your own eyes, because it is not bright or not, and the brightness can only be concluded after seeing it with your own eyes. That is to say, your eyes are a test instrument for the amount of 'laser brightness'. Everyone’s eyes are slightly different. If your eyes are color-blind to red light with a wavelength of 635nm, even if others look at the dazzling red laser with a wavelength of 635nm, you will still feel very dark after seeing it, or even look at it at all. Does not come out.
The human eye has different visual sensitivity to lasers of different wavelengths, so when talking about 'laser brightnessIs that laser light on or off?