The illumination component will consist of several laser light sources along with design-specific beam manipulation optics.
While much of the laser technology being developed at present involves finely focused beams that can even be used as pinpoint “optical tweezers” and which can manipulate individual molecules, the laser technique for this application is much the opposite.
Rather than tightly focussed beams, the optical approach for this clinical application requires a broad beam geometry. Moreover, the profile of a beam leaving the laser aperture is that of a Gaussian.
Contrary to the above, a flattened and expanded beam with a homogeneous energy fluence across the entire beam profile is what is required for this current invention.
Such beam shaping filters do exist and are often known as a “top hat” or “flat top” filter. However, their use is not that common.
Therefore, the most important objective from an optics perspective is to modify a 3 mm to 5 mm diameter input beam with a Gaussian profile to that of a 5 cm diameter output beam with a flat profile that has a uniform energy fluence over its entire area.
Moreover, as all of the photons are expected to be fully absorbed, another matter to consider is the transfer of heat to the blood. The heat absorbed by the blood during the extracorporeal illumination must not be allowed to exceed a clinical threshold. Calculations have already been accomplished that address this issue. Fortunately, the temperature rise of the blood is modest, and mitigation techniques have already been incorporated into design aspects.