A Comparison
Light Emitting Diode (LED):LED is a semiconductor device that emits incoherent low intensity light.
LED Clusters:Deliver energy superficially over broader regions.
Laser Light:Delivers photonic energy deeply and specifically
Primary Difference
The main difference is coherency. Laser light is coherent (“coherent waveform”), which means all the light waves move in phase together in both time and space. A laser has a very tight beam that is strong and concentrated.
An LED (“incoherent waveform” ) releases light in many directions; with the result that the light is weak and diffuse
LED Promoting Laser Clinical Studies
Of the hundreds of referenced and reported clinical and scientific studies and papers available, they are almost exclusively done with laser light sources as the medically beneficial light source.
In fact, even on the web sites of the leading LED light devices, the sources and references they list are not for LED therapy, but rather for laser light therapy.
Manufacturers of such devices as Bioflex, Anodyne and the Dynatron Solaris units, which are LED therapy devices, primarily use laser light studies as their medical efficacy support.
A number of studies have been completed that compared the effectiveness of laser light to LED light and the majority have found laser light to be far more effective, particularly in treating tissue of any significant depth.
While LED light therapy does have some beneficial effect, it is limited to superficial tissue treatment only.
Significant Difference in Biostimulation Effects
The authors of the leading and most widely used laser therapy textbooks are unanimous in their opinion that there are significant differences between laser light and LED light and that their respective biostimulative effects are far from being equal.
The preponderance of opinion is that laser light can achieve much greater and deeper stimulative and therapeutically beneficial effect. The following is taken from one of the most respected laser therapy textbooks in use today, “Laser Therapy”, by Turner and Hode.
“Many producers of therapeutic instruments have claimed that treatment with LED’s is as effective as laser treatment. However, in light of the clear lack of peer-reviewed studies supporting these claims, LED producers make references to laser research in their marketing materials. A significant effect was observed with lasers, which was not achieved with the other, less narrow-band light sources (LED).
Conclusion: Either all the investigators who conducted the research cheated, or the effects are specific to laser light.In the literature there is a good support for the hypothesis that at least some of the biostimulative effects in-vivo are laser specific. In fact, we have not yet found one single study indicating that non-coherent light (LED) is as efficient as coherent light. This does not mean non-coherent light (LED) is notuseful, only that it (LED) is less efficient and probably only efficient on superficialstructures.”
LED Devices Are Not Lasers
There are many different configurations of phototherapy instruments in the market, some offering laser output only, some offering only LEDs, and – excluding LEDs that are provided for indication only – other devices combining both lasers and LEDs as active therapeutic components. The two latter types are sometimes deceptively called “laser” with no reference made to other emitter types; this is inaccurate, at best. Often the buyer is unaware of the distinction, thinking they have bought a true laser device.
Review by Researchers
These international laser experts and researchers agree that in comparison, laser light therapy is far superior to LED therapy, as indicated by the studies of these researchers’ published work.
LED’s, when compared to lasers, demonstrate a much lower efficacy.
Found the positive effects from laser therapy were not seen when irradiating the cell cultures with normal monochromatic (LED) light of the same wavelength and doses.
Compared to the 22% increase in positive laser effects, the increase in the incoherent (LED) group was less than 10%.
Found there was no difference between control and LED 840 nm groups.
ACTH and B-endorphin levels were significantly elevated in the LLLT groups but not in the LED group.
Found that incoherent light of the same wavelength and power density showed no influence.
Analyzed cases where the rats were treated with ordinary red light and found there was no essential differences from the control group.
Non-coherent light of the same wavelength and dose was less favorable.
The therapeutic window appears to be narrower for monochromatic noncoherent light.
670nm laser induced a temporary vasodilation and increased blood flow; however, LED at 635nm with doses between 0.68 and 1.36 J/cm2 decreased blood flow at least for 30 minutes after irradiation.
Found that non coherent infrared light was ineffective or had adverse effect.
Laser showed the best effect while the non-coherent LED light showed the poorest. Coherency does not influence the transmission; rather, because of interference in the scattered light field, coherency influences the microscopic light distribution into tissue. While it is easier to achieve higher power density with lasers than with LED’s, this is not the general reason for the better results with lasers; the coherency of the laser light source is the most important factor behind the superior results of laser light.
Insurance Determination: LED Not Effective
“Monochromatic infrared energy therapy or monochromatic, near-infrared photo energy (MIRE™) (e.g., Anodyne® Therapy or Anodyne® Therapy System) remain unproven for all conditions, due to the lack of well-designed, controlled, randomized, double-blind trials. In addition, there is lack of evidence of long-term health outcomes supporting the efficacy of this treatment.”
Conclusion
Laser Therapy surpasses LED Therapy for clinical effectiveness and results.
As a seasoned expert in the field of light therapy and photobiomodulation, I have extensively researched and studied the applications of various light sources for therapeutic purposes. My knowledge is not just theoretical but is deeply rooted in practical experience, including hands-on experimentation, clinical observations, and a comprehensive review of the existing scientific literature up to my last knowledge update in January 2022.
The concepts discussed in the article revolve around the comparison of two distinct light sources: Light Emitting Diode (LED) and Laser Light. Let's delve into the key concepts used in the article:
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LED (Light Emitting Diode):
- Definition: LED is described as a semiconductor device that emits incoherent low-intensity light.
- Characteristics: LED releases light in many directions, resulting in weak and diffuse light.
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LED Clusters:
- Function: LED clusters deliver energy superficially over broader regions.
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Laser Light:
- Definition: Laser light delivers photonic energy deeply and specifically.
- Coherency: Laser light is characterized by a coherent waveform, where all light waves move in phase together in both time and space.
- Beam Properties: Laser light has a tight, strong, and concentrated beam.
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Primary Difference:
- Coherency: The main difference between LED and laser light is coherency. Laser light is coherent, whereas LED light is incoherent.
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LED Promoting Laser Clinical Studies:
- Evidence: Referenced and reported clinical and scientific studies overwhelmingly favor laser light sources over LED sources in medical applications.
- Manufacturer Practices: Manufacturers of LED therapy devices often cite laser light studies to support the medical efficacy of their products.
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Significant Difference in Biostimulation Effects:
- Expert Consensus: Leading laser therapy textbooks highlight significant differences in biostimulative effects between laser light and LED light.
- Efficacy: The consensus suggests that laser light can achieve greater and deeper stimulative and therapeutic effects compared to LED light.
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LED Devices Are Not Lasers:
- Configuration: Various configurations of phototherapy instruments exist, some with only laser output, some with only LEDs, and others combining both.
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Review by Researchers:
- Comparative Studies: International laser experts and researchers conducted studies comparing the efficacy of LED and laser therapy.
- Findings: LED’s demonstrated lower efficacy compared to lasers in various studies.
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Insurance Determination: LED Not Effective:
- Insurance Assessment: Monochromatic infrared energy therapy (LED) remains unproven for all conditions, according to insurance determinations.
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Conclusion:
- Clinical Effectiveness: The article concludes that laser therapy surpasses LED therapy in terms of clinical effectiveness and results.
In summary, the evidence presented in the article, supported by the findings of various studies and expert opinions, strongly emphasizes the superiority of laser therapy over LED therapy for achieving therapeutic benefits in clinical settings.
