Visible Red Light: Red light at a wavelength of 660 nanometers penetrates tissue to a depth of about 8-10 mm (about 3/8′′). It is very beneficial in treating problems close to the surface such as wounds, cuts, scars, trigger points and acupuncture points, and is particularly effective in treating infections.
Infrared Light: Infrared light is not visible to the eye. It penetrates to a depth of about 30-40 mm (1.2′′ to 1.4′′), which makes it more effective for bones, joints, deep muscles, bursa, etc. Infrared light is one of the safest therapies on the market today. When infrared light is administered, it reduces sensitivity of neural pathways and causes the body to release endorphins that provide a nontoxic, natural form of pain relief. Unlike ultrasound and electrical stimulation, infrared technology is so gentle that patients can use it frequently without causing more damage to injuries or other chronic pathologies.
Although both red and infrared wavelengths penetrate to different depths and affect tissues differently, their therapeutic effects are similar.