1. A release mechanism for releasing a medical device, the release mechanism comprising:
a generally elongate shaft defining a longitudinal axis;
an actuating member receivable in the elongate shaft, the actuating member having an interlocking position and a releasing position; and
at least two, mutually opposed arms at a distal end of the elongate shaft, the arms being biased to open relative to each other, each arm comprising:
a gripping portion at a distal end thereof, and
at least one interlocking member, wherein the gripping portions of the arms at least partially define a hollow space for holding a medical device to be released, the interlocking member of each arm is longitudinally spaced from the interlocking member of any other arm, each interlocking member extends circumferentially around a sufficient proportion of the actuating member such that, when the actuating member is in the interlocking position, opening of the arms is prevented by interaction between the actuating member and the interlocking members, and the actuating member is longitudinally retractable from the interlocking position to the releasing position to enable the arms to open for releasing a medical device from the gripping portions.
2. The release mechanism as claimed in claim 1, wherein the actuating member comprises a substantially cylindrical, elongate member, and each interlocking member extends around more than 180\xb0 of the circumference of the actuating member when the actuating member is in the interlocking position.
3. The release mechanism as claimed in claim 1, wherein each arm further comprises a connecting member, the connecting member of a first one of the at least two, mutually opposed arms is located generally opposite the interlocking member of a second one of the at least two, mutually opposed arms, and the connecting member of the second one of the at least two, mutually opposed arms is located generally opposite the interlocking member of the first one of the at least two, mutually opposed arms.
4. The release mechanism as claimed in claim 3, wherein each interlocking member defining a spacing between end portions of the respective interlocking member, the connecting member of the first one of the at least two, mutually opposed arms is interposed between the end portions of the interlocking member of the second one of the at least two, mutually opposed arms, and the connecting member of the second one of the at least two, mutually opposed arms is interposed between the end portions of the interlocking member of the first one of the at least two, mutually opposed arms.
5. The release mechanism as claimed in claim 1, wherein the mutually opposed arms comprises a pair of arms, each having a longitudinal axis and, when the actuating member is in the interlocking position, the longitudinal axes of the arms are substantially parallel to each other.
6. The release mechanism as claimed in claim 1, wherein each interlocking member comprises a strip joined at least at one end, and at either end, of the strip to the respective arm and depending therefrom in the general direction of an opposing arm wherein each strip and respective arm together extend circumferentially around the actuating member to prevent opening of the arms.
7. The release mechanism as claimed in claim 6, wherein each arm has a generally arcuate inner surface, and each strip is generally arcuate such that the arcuate strip and respective arm together at least partially, and entirely, encircle the actuating member when the actuating member is in the interlocking position.
8. The release mechanism as claimed in claim 6, wherein each strip is integrally formed with a respective arm.
9. The release mechanism as claimed in claim 6, wherein each strip is defined by a pair of circumferential slits in a generally concave portion of the respective arm, the strip between the pair of circumferential slits being deflected inwardly in the general direction of an opposing arm, by pressing on the strips, to form a generally convex arcuate strip.
10. The release mechanism as claimed in claim 1, wherein at least the arms or the elongate shaft are flexible, being formed from a flexible material, comprising a flexible polymeric material being polyimide.
11. The release mechanism as claimed in claim 1, wherein at least the arms or the elongate shaft comprise a flexible metal alloy, being formed from a flexible metal alloy.
12. The release mechanism as claimed in claim 1, wherein the arms are integrally formed with the elongate shaft.
13. The release mechanism as claimed in claim 1, wherein the arms are laser cut from the distal end of the elongate shaft.
14. The release mechanism as claimed in claim 1, wherein the actuating member comprises a wire, the wire being retractable from a proximal end of the elongate shaft to move the actuating member to the releasing position to release the arms.
15. The release mechanism as claimed in claim 1, wherein the hollow space at least partially defined by the gripping portions is configured for holding an embolic coil, an embolic coil having an enlarged head portion at a proximal end thereof, the head portion being substantially spherical.
16. The release mechanism as claimed in claim 1, wherein the gripping portions of the arms define the distal end of the release mechanism and have a dimension generally perpendicular to the longitudinal axis of the elongate shaft that is less than the outer diameter of the elongate shaft so as not to increase the outer profile of the release mechanism when the actuating member is in the interlocking position and the arms are closed.
17. A method of manufacturing a release mechanism for releasing a medical device, the method comprising:
forming a hollow elongate shaft that defines a longitudinal axis; and
cutting to form at least two, mutually opposed arms at a distal end thereof such that the arms are biased to open when unconstrained, each arm having at least one interlocking member and a gripping portion, the gripping portion located at the distal end of the arm, wherein the interlocking member of each arm is longitudinally spaced from the interlocking member of any other arm, the gripping portions are formed so as to at least partially define a hollow space for holding the medical device to be released, and the interlocking members are formed such that each interlocking member extends around a sufficient proportion of an actuating member receivable within the hollow elongate shaft such that opening of the arms is prevented by interaction between the actuating member and the interlocking members.
18. The method of claim 17, further comprising:
cutting a first pair of circumferential slits into a first one of the at least two mutually opposed arms to define a first strip;
cutting a second pair of circumferential slits into a second one of the at least two mutually opposed arms to define a second strip, the second strip being longitudinally spaced from the first strip; and
pressing the first and second strips inwardly in the general direction of an opposing arm to form arcuate strips.
19. The method of claim 18, further comprising introducing an actuating member, comprising an actuating wire, into the lumen defined by each arcuate strip and the respective arm from which it is cut, thereby holding the arms against their bias to open.
20. A method of releasing a medical device at a release location within a body, comprising the steps of:
gripping the medical device by a release mechanism comprising a generally elongate shaft defining a longitudinal axis and at least two, mutually opposed arms at a distal end of the elongate shaft, the arms being biased to open relative to each other and each comprising a gripping portion at a distal end thereof serving to grip the medical device and at least one interlocking member;
locking the release mechanism by positioning an actuating member such that the interlocking members extend circumferentially around a sufficient proportion of the actuating member to prevent opening of the arms;
navigating the release mechanism to the release location; and
retracting the actuating member longitudinally to enable the arms to open so releasing the medical device from the gripping portions.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A hybrid vertical cavity laser comprising:
an optical circuit substrate including,
a grating including lower refractive index units and a higher refractive index unit alternately arranged in a first direction, the lower refractive index units having a lower refractive index than the higher refractive index unit, and
a waveguide guiding light in the first direction;
a mesa structure on the optical circuit substrate, the mesa structure including a first-type semiconductor layer, an active layer, a second-type semiconductor layer, and an upper reflective layer sequentially stacked in a second direction perpendicular to the first direction, the first-type semiconductor layer including an exposed portion;
a first electrode on the exposed portion of the first-type semiconductor layer; and
a second electrode on the upper reflective layer,
wherein an overlapped length between the waveguide and a mesa aperture forming an opening through which light produced from the active layer enters the grating is D, a pitch of the grating is p, and 0<D<p.
2. The hybrid vertical cavity laser of claim 1, wherein the optical circuit substrate comprises:
a first layer;
a second layer on the first layer, the second layer including a material having a refractive index higher than that of the first layer and patterned to form the grating and the waveguide; and
a dielectric material layer on the second layer, the dielectric material layer including a material having a refractive index lower than that of the second layer.
3. The hybrid vertical cavity laser of claim 2, wherein the first layer is formed of silicon oxide, and the second layer is formed of silicon.
4. The hybrid vertical cavity laser of claim 2, wherein
the optical circuit substrate includes a silicon on insulator (SOI) substrate, the SOI substrate including a first silicon layer, a silicon oxide layer, and a second silicon layer,
the silicon oxide layer is the first layer, and
the second silicon layer is patterned to form the second layer.
5. The hybrid vertical cavity laser of claim 1, wherein the higher refractive index unit includes silicon, and the lower refractive index units include air.
6. The hybrid vertical cavity laser of claim 1, wherein a width of lower refractive index units and an interval between neighboring lower refractive index units are constant.
7. The hybrid vertical cavity laser of claim 1, wherein
the lower refractive index units include a first lower refractive index unit and a second lower refractive index unit, the first lower refractive index unit and the second lower refractive index unit having different widths,
the first lower refractive index unit and the second lower refractive index unit are alternately arranged, and
the pitch p of the grating is defined as \xbd of a pitch between neighboring first lower refractive index units.
8. The hybrid vertical cavity laser of claim 7, wherein an interval between neighboring first lower refractive index units and an interval between neighboring second lower refractive index units are constant.
9. The hybrid vertical cavity laser of claim 1, wherein an angle between a side of the mesa structure and the exposed portion of the first-type semiconductor layer is less than 90\xb0.