I have no doubt that you have heard a politician or someone at work say that they are going to “focus like a laser” on some particular area but for someone who understands the actual workings of a laser, that phrase is so wrong from a physics standpoint. If you hear someone say “focus like a magnifying glass” then they’d be on sound physics ground but lasers obtain their energy by not focusing light but by a method that is far more interesting.
I will detail the operation of a laser in this post and then assert how we can use these principles to affect the way we interact with others in our daily life.
To understand lasers we must first understand atoms and quantum physics so let me hit this main points in a way that those of you who don’t have a science background can understand.
Everything around us is comprised of atoms – cats, dogs, baseballs, iPads, trees, desks – and each atom is comprised of three main building blocks (protons, neutrons and electrons). Every atom has a nucleus where protons and neutrons reside and then there is a shell, or cloud, where electrons orbit the nucleus. It was determined a long time ago that these electrons don’t orbit in some random or continuous fashion but instead occupied very specific orbits or energy levels. The laws of quantum physics prove that electrons can only occupy certain energy levels and to move an electron to a higher energy level requires an energy input. Once the electron is moved to this new energy level it will stay there until it drops back down to its ‘normal’ or ground state.
When the electron decays to its ground state (or a lower energy state) the electron gives off energy in a strange particle called a photon. Photons are small packets of energy that make up all electromagnetic radiation and they take on both wave and particle characteristics. Each photon vibrates and has a particular frequency/wavelength and this frequency is important because the energy of the photon is directly proportional to its frequency (i.e. high frequency photons have high energy).
There are two methods to move an electron from an energized state to its ground state – Spontaneous Emission and Stimulated Emission. The electron will naturally ‘want’ to move to its ground state so eventually it will drop down and this is what’s called spontaneous emission. There is a much more interesting type of transition called stimulated emission which happens when a photon interacts with an atom that has an electron in an excited state and that interaction causes the electron to drop to a lower energy level. This new photon that is released via stimulated emission will have the same frequency as the photon that interacted with that atom and essentially creates a twin moving in the same direction and same frequency. This is important because it is the essence of what makes a laser work (which will be explained below) and a diagram of this type of emission is shown below.
Now that the basics of atoms, photons and quantum physics are out of the way, let’s move on to the laser operation and the basic components of a laser are shown in the diagram below.
There is a media that is excited by an energy source (usually a flash lamp) that moves electrons to a higher energy level. After a while, through spontaneous emission, photons are emitted in all directions and those that are perpendicular to the mirrors will start bouncing back and forth. When these photons interact with atoms that have excited electrons, stimulated emission takes place and we have an increase in the number of photons that match the frequency and direction of the original photons and as they bounce back and forth there is an amplification of the photons at a specific frequency and direction (called coherent in physics terms). The mirror on the left is 100% reflective but the mirror on the right is less than 100% reflective and the laser light emerges from this mirror and is translated to the fiber optics that deliver the laser energy.
You can now see why the term ‘laser’ stands for Light Amplification by Stimulated Emission of Radiation.
There is no focusing that generates this high energy light but instead it arises from photons bouncing back and forth and creating twins of itself through stimulated emission. And it was this understanding of stimulated emission that led Charles Townes in 1953 to perform the pioneering work that led to the invention of the laser and he was eventually awarded the Nobel Prize in Physics in 1964.
The laser has changed the way the world operates from manufacturing, retail, communication and defense but there an object lesson we can take from the operation of a laser.
Think about political movements. There is a ‘flash lamp’ that starts the process – i.e. the Tea Party movement – and then all sorts of random emissions come forth from that stimulation. The good ideas are bounced around and that stimulates others to join the movement and soon you have a whole host of individuals who are coherent in their views and actions. Each individual is powerless on their own but when a large group of people join forces around a common ideal and combine their resources a powerful movement is created that can do great things.
Think about Christianity. The Holy Spirit, the ‘flash lamp’, starts the process and excites humans to a higher energy level. This generates all sorts of initial excitement but only the individuals who really understand the message proclaim it and this gets others involved. In His infinite wisdom, God set up Christianity so that others come to belief through the interaction with others. Even after Jesus was resurrected, His message to the Disciples was to go and tell others about Him and in Matthew 29:10 Jesus said the following to the women who found him resurrected at the tomb:
“Do not be afraid. Go and tell my brothers to go to Galilee’ there they will see me.”
Witnesses who share their faith and the saving Grace of Jesus Christ are the vessels that the Holy Spirit uses to share the Gospel to others. In over 2,000 years, very few have had a Damascus road experience like Paul but instead, most come to the saving knowledge of Christ through the interactions with others.
Think about business. A good CEO will communicate a vision that will inspire all sorts of ideas from the employees. As these ideas get communicated and vetted, only those that contribute to the corporate goals get traction and eventually the whole organization is moving in the same direction to accomplish the goals. When people are moving in different directions or if there is infighting then the company is not coherent and can’t move in a direction that supports the business model.
Learn the theory of the laser and understand that people can be like photons – We can influence others by just coming in contact with them. When we decide to occupy our time with what is really important and cast aside the trivial minutia that gets in the way, we can be a force to be reckoned with. Don’t be afraid to come in contact with others and speak you mind because you shouldn’t discount the power of an individual photon. Social media (Blogs, Twitter and Facebook) provides us with tools that were unthinkable 20 years ago and we should use those to spread our influence and stimulate people who are energized but need motivation to move from their chair and enter the conversation.
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