Laser Pointer: How does it work?

You know when you’re attending a meeting and the person presenting is holding a small device that emits a laser dot, to highlight whatever it is they’re explaining? That small device is a laser pointer. But have you ever wondered how it actually works or what laser pointers are used for – apart from making your cat go mad?

Laser pointer uses

Lasers have been used in technological advancements and many areas of science and exploration. With the use of laser, medical achievements have been made where surgeons have found laser useful in diagnosing and treating various types of cancers, experiments in science fields have been possible and laser cutters were designed to create outstanding results. Nowadays, with laser technology advancement, the use of laser is evident in far more common and accessible items such are laser pointers.

Laser pointers are most commonly known to be used during presentations to point out something important on a slide or help follow a diagram being explained from a distance while presenting. If you’ve ever tried to use a laser pointer on a smart TV, you’ll understand the frustration that comes with it. That is mainly because smart televisions contain an LCD or LED screen which works by absorbing incoming light,  allowing viewers to get a better range of colors visible on the screen, and that they require specialized laser pointers. You’ll find that the Logitech Spotlight with a digital laser pointer works best on TV screens, and that if you are planning to use a TV for presentations, then it’s better to look at the reviews and see which pointer would suit your TV best. While that is one of the most common uses, there are other applications and uses for them, too. Green laser pointers, for instance, can be used for stargazing as they usually have higher power and therefore can be used at night.

How do laser pointers work?

In order to understand how laser pointers work, it is wise to understand how lasers work first, in general. Lasers are a small, powerful beam of concentrated light that work to magnify a light source and turn it into a powerful, focused beam.  The word “laser” is an acronym that stands for “light amplification by stimulated emission of radiation.”

The laser light is different from ordinary light or natural light. The main difference is that natural light generally illuminates a large area by allocating light to that area. However, when focusing a laser light into one beam, it is so much more powerful than a natural light that is designed to be distributed amongst larger areas, becoming far less powerful.

Laser pointers are made up of three parts: lasing medium, energy source and a resonator. The lasing medium is a form of light or electricity that can be powered by a source of energy. Light mediums, however, can be found used in the form of minerals, gases or even liquids. When powering a laser diode with a form of energy, the laser pointer will emit a beam of light evident to the naked eye.

When the laser medium is activated, it will discharge the energy as a monochromatic radiation. The resonator then does its job by holding the energy and building it up before it is released. This resonator is composed of a rod that has two mirrors found on each side of the lasing medium. Each mirror has a different task, the solid mirror reflects the light back to the medium, whereas the transparent mirror breaks down and divides the light between the medium and the exit point. When the light bounces between the two mirrors, the resonator is in charge of aligning the beam of the light in one direction, resulting in a solid laser beam.

There are two types of laser pointers: Ruby Lasers and Green lasers:

Ruby Lasers

As evident in the name, the ruby laser projects a red beam of light in the form of a red dot. The laser pointer contains a ruby rod inside it and works exactly as explained above with a mirror reflecting the atoms and the other mirror dividing the light so that it can be visible to the eye in the form of a projection of the light beam onto the targeted surface in the form of a laser dot.

Green Lasers

The most obvious difference between green lasers and ruby lasers are the colors they emit. In this case, instead of a red-colored beam of light, there is a green beam inside the laser point that results in a green beam of light being visible.

When choosing a laser pointer, it is recommended to choose quality, especially with green laser pointers. This is because green lasers can be quite dangerous as they are a lot more powerful due to the fact that the beam of light is very focused. With cheap, green laser pointers, unconverted infrared laser light will most probably not be filtered out, resulting in an invisible laser beam that shines in your eyes without you being able to see it. That means that you will not blink or move because of being unaware of the problem, causing permanent damage to the eyes and could lead to total blindness.

How to safely use your pointer

No matter how high or low the power of the light your laser pointer emits, there are a few points to consider when using a laser pointer:

  • Although it seems obvious, but you should NEVER point your laser directly towards someone’s eye to avoid eye damage.
  • Laser beams should not be used on animals. Even when playing with your cat, make sure the laser is not directed at them.
  • Never look directly into the laser beam, no matter how curious you are.
  • Laser pointers should not be used on any kind of vehicles as they might interfere with the driver’s focus and lead to accidents.
  • Understand that reflective surfaces will cause the laser beam to bounce off it, and so be aware of them and use them accordingly.
  • Avoid using the laser on the skin, especially for a long period of time.

The fascination with laser and laser pointers has been extremely common since their release. But while they started out as just a game, they are now a device that can come in really handy, especially in the areas of education and public speaking. If you’re using in the habit of presenting occasionally, then getting yourself a laser pointer will make your life a whole lot easier when presenting. Just remember the precautions above and you’ll be good to go.