Laser energy, energy density, fluence, leprechauns and star bursts……

  I constantly hear laser users talking about the ‘energy’ they are using to treat tattoos, hair, blood vessels etc. However, it is clear that many don’t really understand what they mean. I often read about treatments using “500” or “250” or “never above 600” joules, millijoules or whatever!! I think these are the numbers… Continue reading Laser energy, energy density, fluence, leprechauns and star bursts……

What is your weight on Mars? Or other planets???

  There is a curious anomaly around today. When we discuss our weight we invariably refer to the number of kilograms we ‘weigh’. But this is a measurement of mass, not weight! So, if someone claim a weight of 100 kg, they are really referring to their mass. This is where it gets interesting. To… Continue reading What is your weight on Mars? Or other planets???

Single or Double Rod Nd:YAG Lasers?

  Nowadays, it is possible to purchase Q-switched Nd:YAG lasers with a single YAG rod, or with two rods. So, what is the difference and is it important? To understand why a laser might have two rods instead of one we should look at the basic design of a laser first. Basic laser cavity A… Continue reading Single or Double Rod Nd:YAG Lasers?