Steering light in fiber-optic medical devices: a patent review

Abstract

Introduction Steering light is relevant to many medical applications that require tissue illumination, sensing, or modification. To control the propagation direction of light beams, a great variety of innovative fiber-optic medical devices have been designed. Areas covered This review provides a comprehensive overview of the patent literature on light beam control in fiber-optic medical devices. The Web of Science Derwent Innovation Index database was scanned, and 81 patents on fiber-optic devices published in the last 20 years (2001–2021) were retrieved and categorized based on the working principle to steer light (refraction/reflection, scattering, diffraction) and the design strategy that was employed (within fiber, at fiber end, outside fiber). Expert opinion Patents describing medical devices were found for all categories, except for generating diffraction at the fiber end surface. The insight in the different designs reveals that there are still several opportunities to design innovative devices that can collect light at an angle off-axis, reduce the angular distribution of light, or split light into multiple beams.

Optical Fibre-Based Sensors—An Assessment of Current Innovations

“…These sensing mechanisms can be combined or adapted to various types of optical fibre sensors to measure a wide range of physical quantities such as temperature, strain, pressure, humidity, chemical composition, and more [ 80 , 81 , 82 ]. The choice of sensing mechanism depends on the specific application requirements and the target variable being measured [ 83 ].…”

“…The plasmonic element typically consists of metallic nanoparticles, nanowires, or thin films deposited on the fibre’s surface or within its core [ 82 ]. These plasmonic structures interact with the evanescent field of light propagating through the fibre, allowing the detection of analytes or changes in the surrounding environment [ 83 ]. Another highly sensitive temperature sensor is proposed based on PCF utilizing a flat metal-coated trapezoidal surface, as shown in Figure 5 b [ 104 ].…”

Seeing from a new angle: design of a sideways-looking fiber-optic probe to advance spine surgery

“…Through design of the distal end of a fiber-optic medical device, the light path is determined, which offers potential to control the angular distribution of light, and to emit and collect light off axis to allow for sidewaysdirected DRS measurements. 10 Emitting light diffusely into the tissue through a diffuser tip will increase the illuminated volume. 11 To cover the full range of impending cortical breaches whilst keeping the complexity of the probe low and minimizing the amount of fibers used, the probed volume can be manipulated with obliquely oriented collecting fibers.…”

Preliminary Results of Laser Ablation during In Vivo Experiments: Comparison of Thermal Effects Obtained with Bare and Diffuser Tip Applicators

“…This allows also treating tumors in particular locations, such as brain, thyroid, pancreas, breast, and liver. The mechanical and optical characteristics of the optical fiber which constitutes the laser applicator affect the way the photons are delivered inside the tumor, in terms of spatial distribution of the light and power density [6]. Therefore, having information about the shape and size of the induced thermal lesions, along with the temperature gradient, is a key factor to guarantee a safe and successful LA.…”