Light emitting diode (LED) light sources are unique in that they emit a narrow spectrum in an uncorrelated fashion. LEDs were invented in 1962, but early LEDs lacked the ability to generate biorelevant energy. In addition, the emitted wavelengths are broad, with variations of up to 100nm. In the 1990s, NASA redeveloped the LED, which produced a light spectrum so narrow that it allowed its first clinical application. Over the past few decades, the demand for LED phototherapy biology has increased, and effective dermatological treatment has led to a growing interest in LED devices.

In the early 1990s, people realized the biological significance of light-emitting diodes. Since this discovery, the effects of various light sources on human skin have been studied. It acts on anti-aging, anti-freckle and hair loss and so on.

Findings: Several reports based on real cases and a number of randomized controlled trials evaluating the use of light-emitting diodes at four different wavelengths were identified. Classified as red, blue, yellow or infrared, these LEDs cover a wide range of clinical applications. The 21 patients who participated in the study treatment had mixed results in terms of satisfaction and improvement in clinical appearance before and after treatment.

Conclusion: The literature review shows that light-emitting diode devices with different wavelengths have many beneficial effects, including aiding wound healing, treating acne, preventing sunburn, facial wrinkle reduction, and cell regeneration, among others. Clinical responses to specific yellow LED devices have been variable, depending on the condition being treated, and may be influenced by device parameters.

FDA-approved brand is the application effect:

There are many manufacturers of LED lights that produce different wavelengths of light, such as Photo Therapeutics, Inc. of Carlsbad, CA, which sells a variety of LED light therapy products under the Omnilux© brand name. Omnilux PDT™ (633nm) is indicated for non-melanoma skin cancer (NMSC). Omnilux Revive™ (633nm) is a red light device for skin regeneration. It produces about 30% more output energy than PDT devices. Omnilux Blue™ (415nm) is approved for the treatment of acne and actinic keratoses (AKs). Omnilux Plus™ (830nm) is an infrared device for skin cell regeneration and wound healing.

Recently, Ambicare Health in Scotland developed a portable PDT device called the Ambulight PDT™. Ibbotson and Ferguson12 have shown that it is as effective and less painful than traditional PDT in treating non-melanoma skin cancers due to its lower irradiance. It can be considered as an alternative to traditional PDT.

Light Bioscience of Virginia Beach, VA manufactures the yellow light device GentleWaves® LED Photomodulation® (590nm). It delivers 35 seconds of therapy in a patented 102 millisecond pulse cycle. While pulsed light proved effective during testing, continuous light delivery was not proven effective during initial testing of the device.

Anodyne Therapy, LLC of Tampa, FL sells the MIRE Therapy System (890nm). This device is used to improve blood circulation and reduce pain, stiff skin, and muscle spasms.