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A low cost light diffuser made of metal coil
Nozomi Morita1, Tsunenori Arai
1School of fundamental Science and Technology, Graduate School of Science and Technology Keio University (Japan).
Summary
We developed a low-cost, flexible metal coil light diffuser for precise laser therapy in narrow organs. This coil effectively diffuses light, improving therapeutic outcomes and minimizing energy loss.
Area of Science:
- Biomedical Engineering
- Optical Physics
- Materials Science
Background:
- Delivering precise light doses in laser therapies within narrow, bending organs is challenging.
- Existing light diffusers may lack flexibility or cost-effectiveness for such applications.
Purpose of the Study:
- To develop and evaluate a novel, low-cost, flexible light diffuser for laser therapies.
- To optimize light diffusion characteristics for effective treatment in confined anatomical spaces.
Main Methods:
- Fabrication of prototype diffusers using stainless steel (sus304) coils.
- Experimental measurement of light intensity distribution (FWHM) along and around the coils.
- Analysis of light diffusion parameters including pitch distance and numerical aperture (NA).
- Measurement of temperature elevation to assess energy waste.
Main Results:
- Achieved a Full Width at Half Maximum (FWHM) of 12.8 mm with constant pitch (0.09 mm) and NA (0.038).
- Improved FWHM to 13.7 mm using composite pitch coils (0.09 mm proximal, 0.18 mm distal).
- Identified significant energy loss to heat (approx. 90%) with 50% surface reflectance.
Conclusions:
- The metal coil light diffuser offers a flexible and potentially low-cost solution for laser dosimetry in challenging anatomical locations.
- Optimizing coil pitch and surface reflectance can enhance diffusion efficiency.
- Further improvements in surface reflectivity are needed to maximize light delivery and minimize thermal waste.
