Laser light is widely used in our lives, it can be seen in various occasions like in a bar, on a concert, in a Christamas party and so forth. Although laser light is commen, we selcom think about how it is made and what its operating principle is. In this article the auther will show you how to make a laser light. After mastered this, you can make one a laser light on your own!
What is laser
Before we start, we’d better learn what is laser so as to understand the operating principle of laser light. According to wikipedia, laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. It differs from other sources of light in that it emits light coherently, spatially and temporally.
Nowadays, laser shows up in a really wide range of products and technologies—CD players, dental drills, high-speed metal cutting machines, measuring systems—almost every aspect of our social lives. Therefore, laser is indispensible to our lives.
How laser works
Now that we’ve learned the nature of laser, let’s see how it works. A laser is created when the electrons in atoms in special glasses, crystals, or gases absorb energy from an electrical current or another laser and become “excited.”
The excited electrons move from a lower-energy orbit to a higher-energy orbit around the atom’s nucleus. When they return to the normal state, the electrons emit photons (particles of light).
These photons are all at the same wavelength and are “coherent”, and this explains two characteristics of laser light. First, laser light is of one specific color because it contains only one wavelength. Second, laser light is a tight beam because it is coherent. (Click here to know more about how laser works.)
How to make a laser light
There are several ways to make a laser light. To make sure that you guys succeed at the first time, a comparatively easy way will be introduced here. Now, let’s see how to make your laser light by using LED.
Step1: Prepare a LED. Two qualities should be satisfied. First, its wavelength should be about 560 nm. Our eyes are not equally sensitive to all wavelengths, they peak at a yellowish-green wavelength of about 560 nm, therefore a LED near that wavelength region will create a brighter spot. Second, its output power should be at least 3 milliwatts.
Step 2: Prepare a battery to supply the needed voltage, a lithium cell, for example. Read the specification sheet of the LED and find its forward voltage before you decide which battery to use.
Step 3: Calculate the size of a current limiting resistor. Here’s the equation: R = (supply voltage – LED forward voltage) / (operating current).
Step 4: Prepare a 10 mm diameter/10 mm focal length lens.
Step 5: Wire the LED circuit, then connect the LED with the resistor and the lithium cell through the switch.
Step 6: Place the assembled circuit in a holder and bond it in place. (The diameter of the holder should fit that of the lens.)
Now you’ve finished. Aim your laser light on the wall and you’ll see a light spot.
In this article, what laser is, what laser’s operating principle is and how to make a laser light are introduced and I hope you’ve got a overall understanding of laser light. What about making a cool laser light by yourself now? If you think the way introduced above is too easy for you, click here to learn more from wikiHow and challenge yourself. When you are doing this, do appropriately and remenber to take some measures to protect yourself as the process may be a little dangerous.