Paddles used in Lipo Laser Machines
A lipo laser would have a few paddles, and each paddle would have a bunch of diodes fitted onto it. The goodness of a lipo laser (and LED) machine would be measured by three things: (a) the number of existing paddles and the number of paddles that can be added on, (b) the number of diodes per paddle and (c) the penetration depth of the diodes at peak and at the lowest point, measured by the wavelength.
So clearly, the number and quality of paddles is key to the goodness of the overall lipo laser machine. A lot of the machines that we recommend start at a minimum of 4 paddles, each of which have a lot of deeply-penetrating diodes. And in many of these, one could add on more paddles, up to 8-20 (depending upon the brand and model of the lipo laser machine).
On the flip side, it is not too easy to manage to many paddles while running a laser session in real life, so some of the top brands also manufacture larger paddles to cover more area faster, but keep away from the hassle of managing too many small paddles.
An important factor is to look at how many diodes of how much penetration capability (laser generation wavelength: measured in nm) exist per paddle, and at what kind of uniformity of distribution. Note that the fluence of the paddle (the "brightness" emerging out of the diodes on the paddle arms) needs to be uniformly distributed for all-round penetration. So the uniformity of diode distribution is very important when assessing the goodness of a lipo laser. The penetration of the diodes are in the 670-635 nm range (over the different generations, the high-end diodes these days go as low as 635 nm, making them very powerful and effective), and at the other extreme, for starting the process, around the 980-1060 nm range.
Cooling of the paddles is important to avoid bruises on the patients body from overheating. Some of the newer paddles have cooling systems built in, so that the paddles and diodes do not heat up too much (such as Body Slender). Some others have tiny fans built on to the paddle, which keeps the paddles cool while they work by taking some of the heat away.
And finally, the make of the paddles is also another factor to consider. The modern ones are made of fiberglass - some are high quality plastic. Times have moved on, and the older-day stainless steel paddles are no longer manufactured much. Fiberglass is the most preferred option for most, because they are lightweight, robust and effective.