Behind the Beam: Power Considerations for Medical Lasers

When designing power supplies for your laser system, consider the device’s complexity, need for flexibility, and other factors.

Gopal Mitra, Global Segment Leader – Industrial

May 29, 2024

5 Min Read
surgical medical lasers
Due to the narrower beams emitted in medical laser devices, surgical use cases require highly sensitive frequencies.Brownie Harris/The Image Bank via Getty Images

At a Glance

  • Lasers are advancing for surgery, dentistry, dermatology, and spectroscopy.
  • Lasers must be operated at the correct frequency and power for medical uses.
  • Don’t let inefficiency and noise detract from your design.

Since the invention of the first laser more than 60 years ago, laser technology has been harnessed for a wide range of applications. When compared with other electromechanical mediums, lasers offer levels of precision, power, and versatility that make them highly preferred for critical and precise use cases. In medical procedures, for example, laser-based treatments offer patients a minimally invasive option to address various health disorders. 

Maximizing the benefits of these powerful tools requires the combined expertise of medical practitioners, device makers, and power design engineers as laser-based medical technology presents unique power challenges. The correct power supplies in a laser for medical use can mean the difference between brilliant new applications and complicated hazards.

The Role of Lasers in Modern Medicine 

In terms of medical applications, lasers can be used to treat conditions such as nonmelanoma skin cancers, the shrinking or destruction of tumors, and polyp removal. Laser technology, due to its highly directional precision, is also commonly used to remove unwanted or abnormal blood vessels in the skin. In cases that require lasers to come in contact with a patient either externally or internally, lasers need to be finely tuned.

Surgical processes don’t call for the high-power outputs that industrial-based applications require as there is, of course, a stark difference between cutting steel and treating a patient. Due to the narrower beams emitted in medical laser devices, medical use cases require highly sensitive frequencies.

As a result, applications in the medical space require unique power supplies to properly dictate the necessary output of pulse width, frequency, amplitude, and other specifications. Interestingly, like the adage that no two snowflakes are alike, no two applications of lasers in the medical space are the same.


Examples of how lasers are utilized in medical treatments include:

  • Surgery. Lasers are commonly used for procedures such as laser-assisted in situ keratomileusis (LASIK) for vision correction as well as treatment for kidney stones, endometriosis, and certain cancers. For oncology in particular, laser-induced interstitial thermotherapy (LITT) and photodynamic therapy (PDT) are used to treat illnesses including epilepsy and brain tumors. 

  • Dentistry. Lasers are used in dentistry for removing tooth decay in preparation for cavity filling, gum disease treatment, and some forms of oral surgery. Other laser dentistry applications such as teeth whitening require increased sensitivity as numbing agents are typically not needed for the procedure.  

  • Dermatology. Though commonly associated with cosmetic procedures such as photorejuvenation or the removal of unwanted hair, there are a wide range of unique laser therapies and treatments in the dermatology field for the treatment of non-cosmetic issues, including actinic keratosis (precancerous lesions), that require specialized power supplies. 

  • Spectroscopy. This branch of scientific medicine deals with the measurement and investigation of spectra produced when matter interacts with or emits electromagnetic radiation. In a laboratory, lasers can be used to make light interact with biological tissue to obtain information about the nature and state of diseases affecting the tissue to better inform diagnoses.

While laser design is typically unique to the manufacturer, ensuring that the power supply can be set and controlled by the operator is paramount to maximize the efficacy of the laser and help ensure proper functionality. Inherently, lasers must be well supported by their power supplies to reliably energize the gain medium. The corresponding output has its own specific frequencies that are unique to a predetermined application. When using lasers for medical procedures, incorrect power frequencies could result in making incisions that aren’t deep enough or are too wide, causing potentially catastrophic results when working on human tissue.  

As there is virtually no acceptable margin of error when it comes to treating patients, lasers for medical applications must be finely tuned, maintained, and operated at the correct frequency and power. The unique and sometimes life-saving applications have a range of power considerations that must be considered, including power design flexibility and noise reduction.   


Laser Choice Based on Use Cases, Power Design Flexibility, and Noise Reduction 

In medical applications, depending on the procedure, the unique features and characteristics of specific types of lasers dictate their respective use cases. Due to their ability to deliver precise, versatile thermal energy that is minimally invasive, CO2 and Yttrium Aluminum Garnet (YAG) lasers are commonly used in medical procedures. Applications for COlasers include skin resurfacing and rejuvenation, gynecological surgery, dental surgery, and veterinary medicine, while YAG lasers are often used for LASIK procedures, removal of lesions, trans myocardial revascularization, and breaking down kidney or bladder stones.

As lasers become more complex, there will be a need for power design flexibility to support a range of alternate voltages for multiple, varying power output needs. For example, the power supply may need to provide both the power required for the laser to function optimally as well as to keep a health-check circuit alive. To support this, power supplies can be designed to deliver a required alternate voltage while also concurrently providing reliable power needed for the laser’s radiation source. In medical applications, lasers also have a specific requirement for isolation due to patient contact, which makes it critical that the frequency control of the power supply has high fidelity. 

Due to heat rejection and the extensive amount of cooling that laser systems require, lasers can be relatively inefficient and noisy machines when in use. The noise associated with the cooling process can also detract from the benefits of using lasers in medical environments by distracting the efforts of surgeons and support staff in the treatment of patients. In such cases, increased fan speeds or the utilization of conduction cooling can help dissipate heat while reducing noise.


Precision, Progress, and Patient Care 

When treating patients, lasers enable surgeons to accomplish more complex tasks, curtail blood loss, and reduce the chance of infection. Lasers will continue to have a diverse and enduring presence in medical applications due to their high reliability, precision, and ability to yield consistent results. 

By fine tuning power supplies to meet individual application needs, power design engineers can help medical practitioners successfully utilize these powerful tools to deliver positive outcomes for patients.

About the Author(s)

Gopal Mitra

Global Segment Leader – Industrial, OmniOn Power

Gopal Mitra is the global segment leader for industrial at OmniOn Power, which designs, develops, and manufactures reliable, high-quality power solutions for mission-critical applications. He works closely with customers to understand and help address their toughest power challenges in applications such as robotics, electric vehicle charging, and lasers.

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