Via the San Francisco Chronicle we learned about a Petaluma, California startup called Raydiance Inc., a firm that developed a type of laser which “generates an ultrashort burst of photons so intense that it can vaporize matter without creating heat.” The Ultrashort pulse (USP) laser technology implemented in the company’s desktop-size laser unit is thought to offer a great deal of medical applications, such as directed killing of cancer cells, or even tattoo removal, according to the Chronicle.
Here’s what the company says:
The Raydiance breakthrough came in developing a desktop-size USP laser that could deliver power levels that could achieve non-thermal ablation in a device small and robust enough to have practical applications. Raydiance has transformed USP technology by shrinking a laboratory behemoth down to a desktop Internet appliance that is “plug and play”.
Equally important, Raydiance has infused the laser with integrated software control. A user simply controls the laser from a graphical interface on a laptop. Virtually every step in pulse generation is monitored and controlled by embedded microprocessors. Researchers with little or no laser experience, for example, those in medical-related fields, can spend their time developing application breakthroughs rather than worrying about tedious fine tuning of the laser before and during every experiment…
USP lasers and traditional continuous wave (CW) lasers differ fundamentally in the way they interact with matter, particularly in the ablation process (removal of material). A CW laser uses a process of linear excitation, generating substantial heat during ablation. The heat generated transfers to the area surrounding the target, leading to melting, material reflow or tissue charring.
USP lasers, by contrast, ablate via a non-linear process called multi-photon ionization. Due to the extreme brevity of the light pulses (typically a trillionth of a second), the energy concentrated in the ultrashort pulse produces a peak power large enough to disrupt the atomic bonds of the target material, resulting in electrostatic forces that expel material from the surface. This process happens at a rate such that the energy of the laser goes into vaporizing material before it can be converted to heat and transferred to materials near the target zone…
The combination of dramatic size and cost reductions with integrated software control leads to limitless research and application possibilities and widespread development of USP laser-based products and services. Whether the desire is to precisely diagnose and ablate malignant tissue at the cellular level or identify the presence of hazardous materials at a distance, Raydiance is the engine powering these breakthroughs.
The extremely short pulses generated by USP lasers offer important applications benefits:
Minimal heat is transferred from the target to surrounding material, resulting in extraordinarily clean and precise ablation. Ablation with micron-level resolution is easily achieved. The non-linear ablation mechanism is materials agnostic: any material can be ablated, including reflective and transparent materials. USP lasers can be utilized at lower average powers and/or energies for diagnostic and remote sensing applications. The short duration of the pulses and their high electric field enables precise temporal and spatial resolution for imaging/diagnostic applications. These include time-resolved optical tomography, laser image detection and ranging (LIDAR), laser detection and ranging (LADAR), and multi-photon fluorescence spectroscopy. Other photodynamic effects, such as stimulated gene transfection and the suppression of metabolic activity in cancer cells, have been induced via USP lasers.
Among applications under development, Raydiance lists cancer treatment, vision correction, cosmetic treatments, nano science applications, and applications in genomics.
To learn more about Ultrashort pulse (USP) laser technology go to the company page or a SF Chronicle article: Laser precision, no heat.