BSS-only multi-sport laser probe

1. An optical surgical probe comprising:

a cylindrical cannula;

a light guide partially within the cannula, configured

to receive a light beam from a light source through a proximal end,

to guide the light beam to a distal end of the light guide, and

to emit the light beam through the distal end of the light guide;

a multi-spot generator at a distal end of the cannula, the multi-spot generator including

an optical element with a proximal surface to receive the emitted light beam, the optical element having an index of refraction n oe in the range of 1.45-1.70; and

a focusing lens comprising at least one of a ball lens, a plano-convex lens, a bi-convex lens, a concave-convex lens, and a meniscus lens, positioned inside the optical element to focus the received light beam into a focused beam, the focusing lens having an index of refraction n fl in the range of 1.65-1.85, wherein

the optical element has a faceted distal surface comprising at least one facet forming an acute facet-angle in the range of 20-60 degrees with respect to a portion of an optical axis centered in the cannula proximal to the faceted distal surface, the at least one facet configured

to split the focused beam into multiple distally emitted beam-components when the optical surgical probe is operated in a fluid with a fluid index of refraction in the range of 1.30-1.40, and

to confine the focused beam into the optical surgical probe when the optical surgical probe is operated in air.

2. The optical surgical probe of claim 1 , wherein:

the fluid index of refraction is in the range of 1.35-1.37.

3. The optical surgical probe of claim 1 , wherein:

the fluid is a balanced saline solution.

4. The optical surgical probe of claim 1 , wherein:

the faceted distal surface is configured to confine the focused beam without distally emitting beam components when the optical surgical probe is operated in air.

5. The optical surgical probe of claim 1 , wherein:

the index of refraction n oe of the optical element is within 20% of the median of the fluid index of refraction n f and an index of refraction n fl of the focusing lens.

6. The optical surgical probe according to claim 1 , wherein:

the index of refraction no, of the optical element is in the 1.50-1.65 range.

7. The optical surgical probe of claim 1 , wherein:

the focusing lens comprises at least one of sapphire, ruby, zirconia, silica, and glass.

8. The optical surgical probe of claim 1 , wherein:

the optical element comprises a cured adhesive.

9. The optical surgical probe of claim 1 , wherein:

the fluid with the fluid index of refraction in the range of 1.30-1.40 is a balanced saline solution.

10. The optical surgical probe of claim 9 , wherein:

facet-angles of the faceted distal surface and an index of refraction n oe of the optical element are configured to confine and reverse the focused beam in a proximal direction through two sequential total internal reflections when the optical surgical probe is operated in air.

11. The optical surgical probe of claim 10 , wherein:

the two sequential total internal reflections reverse the focused beam back into the light guide.

12. The optical surgical probe of claim 1 , wherein:

a distal end of the optical element is proximal to the distal end of the cannula.

13. The optical surgical probe of claim 1 , wherein:

a distal end of the optical element is distal to the distal end of the cannula.

14. The optical surgical probe of claim 1 , wherein:

the proximal surface of the optical element is a planar surface.

15. An optical surgical probe comprising:

a cylindrical cannula;

a light guide partially within the cannula, configured to

receive a light beam from a light source through a proximal end,

guide the light beam to a distal end of the light guide, and

emit the light beam through the distal end of the light guide;

a multi-spot generator at a distal end of the cannula, the multi-spot generator comprising:

an optical element with a proximal surface to receive the emitted light beam, the optical element having an index of refraction n oe in the range of 1.45-1.70; and

a focusing lens comprising at least one of a ball lens, a plano-convex lens, a bi-convex lens, a concave-convex lens, and a meniscus lens, positioned inside the optical element to focus the received light beam into a focused beam, the focusing lens having an index of refraction n fl in the range of 1.65-1.85;

wherein a distal surface of the optical element comprises at least one facet forming an acute facet-angle in the range of 20-60 degrees with respect to a portion of an optical axis centered in the cannula proximal to the distal surface, the at least one facet-angle configured

to split the focused beam into multiple distally emitted beam-components in response to immersion in a fluid with a fluid index of refraction in the range of 1.30-1.40; and

to confine the focused beam into the optical surgical probe in response to interfacing with air.

16. A method, comprising:

generating, by a light source of an optical surgical probe, a light beam;

receiving the light beam through a proximal end of a light guide situated partially within a cannula of the optical surgical probe;

guiding the light beam to a distal end of the light guide;

emitting the light beam through the distal end of the light guide;

receiving the emitted light beam at a focusing lens positioned inside an optical element of a multi-spot generator situated at a distal end of the cannula, the optical element having an index of refraction n oe in the range of 1.45-1.70;

focusing the emitted light beam into a focused beam by a focusing lens comprising at least one of a ball lens, a plano-convex lens, a bi-convex lens, a concave-convex lens, and a meniscus lens, the focusing lens having an index of refraction n fl in the range of 1.65-1.85;

splitting, by a faceted distal surface of the optical element angled acutely in the range of 20-60 degrees with respect to a portion of an optical axis centered in the cannula proximal to the distal surface, the focused beam into multiple distally emitted beam-components when the optical surgical probe is operated in a fluid with a fluid index of refraction in the range of 1.30-1.40; and

confining, by the faceted distal surface of the optical element, the focused beam into the optical surgical probe when the optical surgical probe is operated in air.