Phototherapy is widely used in the field of pain management, mainly through different wavelengths of light acting 

on the human body, promoting cell repair, relieving inflammation, improving blood circulation, so as to achieve the 

effect of relieving pain and promoting recovery. Different wavelengths of light have different effects, the following 

are some common wavelengths of light therapy and their effects:

1. Red light (600-700nm)

Function: red light has strong penetrating power, which can penetrate into the superficial layers of the skin, promote 

blood circulation, reduce muscle tension and inflammation, and relieve pain caused by soft tissue injuries.

Applications:

Relieve muscle pain and arthritis

Improve blood circulation

Promote cell repair

2. Near infrared light (700-1000nm)

Effects: Near infrared light can penetrate deeper into the skin and act on the deeper layers of muscles and joints, 

promoting tissue repair and relieving deep pain.

Applications:

Relieve pain in deep tissues, such as back, spine, knee, etc.

Accelerates healing of damaged tissues

Relieve chronic pain, such as chronic arthritis

3. Blue light (450-495nm)

Effects: Blue light is mainly used for antibacterial and anti-inflammatory purposes as well as relieving localized pain. 

It has a strong inhibitory effect and can reduce the inflammatory response and relieve acute pain.

Applications:

Relief of acute muscle and joint pain

Anti-inflammatory effect to reduce local inflammation

Relief of pain caused by inflammation

4. Ultraviolet light (UV-A 320-400nm, UV-B 280-320nm)

Effects: UV rays relieve pain mainly by promoting blood circulation and enhancing the function of the immune system, 

applicable to some chronic pain and pain caused by skin diseases.

Applications:

Relieving pain caused by arthritis

Treatment of pain associated with skin diseases (e.g. vitiligo)

Improve blood supply to muscles and reduce muscle tension

5. Low intensity laser light (usually in the range of 600-1000nm)

Action: low intensity laser light stimulates cellular repair through the photochemical action of light, relieves chronic 

pain in muscles and joints, and promotes healing of damaged tissues.

Applications:

Relieving chronic muscle and joint pain

Promote healing of wounds and soft tissues

Relieve pain caused by sports injuries or long-term strain injuries

6. Green light (500-570nm)

Effects: Green light has a calming effect and can soothe muscles, relieve tension and pain. It is suitable for relieving 

pain caused by neurological or muscle tension.

Applications:

Relieving neuropathic pain

Relaxes muscles, relieves tension and pain

Summary:

Light therapy can effectively relieve all types of pain in muscles, joints, nerves, etc. by applying different wavelengths 

of light to the body. Red light, near-infrared light, blue light, ultraviolet light, and low intensity laser each have different 

effects, which can promote blood circulation, accelerate cell repair, and reduce inflammation, thus effectively relieving 

different types of pain and promoting recovery.