Coherent photons, which are particles of electromagnetic energy, are emitted from an infrared cold laser (also referred to as low level laser, soft laser or therapeutic laser). These particles enter the tissues and are absorbed in the mitochondria – which are tiny structures within the substance of each individual cell. The energy is converted to chemical energy within the cell.
The permeability of the cell membrane then changes, which in turn produces various physiological effects. These physiological changes affect a variety of cell types including macrophages, fibroblasts, endothelial cells and mast cells, resulting in wound healing, pain relief, reduced inflammation, drainage, etc. This is a pressure sore that refused to heal until treated with infrared laser light therapy:
When comparing lasers, two measurements are key. The first is the wavelength, which determines the color of the light and is measured in nanometers (nm). The second classification is the power of the laser, which is measured in milliwatts (mW). A laser of 500 mW or less is classified as a Category 3, cold laser. This means there is no danger of burning the skin or tissues, or causing damage from overheating. Lasers that are stronger than 500 mW are classified as Category 4 lasers and these should only be used by professionals, or in conjunction with a device that monitors the temperature of the tissue during exposure.
Another defining characteristic of laser light is that it is coherent light. This means that if you shine the light against the wall and then you back up farther and farther away, the laser point will stay the same size. If you happen to have a laser pen that is just an LED, then as you back away the light will fan out – this is the quick way to tell the difference between the two.
Simple colored laser lights have an affinity for the same color. For example, if you set up a green balloon that has a red balloon inflated inside it, and then you shine a red laser light on the balloons, the red balloon inside will pop, but the green one will stay intact. This is because the red laser has an affinity for the red balloon only.
However, infrared lasers are “colorblind” so they will penetrate deeply into tissue. An infrared laser light needs to be a minimum of 650 nm and 5 mW – at this strength it will penetrate almost half an inch into the skin. So if you have a shallow wound or an abscess, this strength is probably sufficient and infrared laser pen lights of this strength can be purchased fairly inexpensively.