Multi-spot laser probe with micro-structured faceted proximal surface
View Patent ↗An optical surgical probe includes a cannula; a light guide within the cannula, configured to receive a light beam from the light source, to guide the light beam to a distal end of the light guide, and to emit the light beam at the distal end of the light guide; and a multi-spot generator at a distal end of the cannula, the multi-spot generator having a faceted proximal surface with oblique facets, configured to receive the light beam emitted at the distal end of the light guide and to split the received light beam into multiple beam-components, and a distal surface through which the multiple beam-components exit the multi-spot generator, wherein the proximal surface of the multi-spot generator is micro-structured with a modulation length smaller than a wavelength of the light beam in order to reduce the reflectance of light back into the probe.
1. An optical surgical probe comprising:
a cylindrical cannula;
a light guide within the cannula, the light guide configured to receive a light beam from a light source, to guide the light beam to a distal end of the light guide, and to emit the light beam at the distal end of the light guide; and
a multi-spot generator at a distal end of the cannula, the multi-spot generator having a faceted proximal surface with oblique facets, configured to receive the light beam emitted at the distal end of the light guide and to split the received light beam into multiple beam-components, an a distal surface through which the multiple beam-components exit the multi-spot generator, wherein the proximal surface of the multi-spot generator is micro-structured with a modulation length smaller than a wavelength of the light beam.
2. The probe of claim 1 , the proximal surface of the multi-spot generator comprising:
micro-structures, with an average separation less than the wavelength of the light beam.
3. The probe of claim 2 , the micro-structures comprising at least one of: bumps, cones, prisms, pyramids, grooves, troughs, divots and a relief pattern.
4. The probe according to claim 1 , wherein: the proximal surface of the multi-spot generator has a moth's eye structure.
5. The probe according to claim 1 , wherein: the proximal surface of the multi-spot generator is micro-structured to have an effective index of refraction that reduces a reflection of the light beam by the proximal surface of the multi-spot generator to below 1%.
6. The probe of claim 1 , the multi-spot generator comprising:
a cured adhesive medium at a distal end of the cannula, the micro-structured proximal surface being formed at a proximal surface of the adhesive medium; and
a ball lens, disposed in the cured adhesive medium.
7. The probe of claim 6 , the ball lens comprising:
a sapphire ball lens.
8. The probe of claim 1 , the multi-spot generator comprising:
a distal surface, micro-structured with a modulation length smaller than the wavelength of the light beam; and the proximal surface and the distal surface of the multi-spot generator are micro-structured to have effective indices of refraction that reduce an overall reflection of the light beam by the multi-spot generator to below 1%.