Waveguide neural interface device

Abstract

Waveguide neural interface devices and methods for fabricating such devices are provided herein. An exemplary interface device includes a neural device comprising an exterior neural device sidewall extending to a distal end portion of the neural device, an array of electrode sites supported by a first face of the neural device sidewall. The array includes a recording electrode site. The exemplary interface device further includes a waveguide extending along the neural device, the waveguide having a distal end to emit light to illuminate targeted tissue adjacent to the recording electrode site, and a light redirecting element disposed at the distal end of the waveguide. The light redirecting element redirects light traveling through the waveguide in a manner that avoids direct illumination of the recording electrode site on the first face of the neural device sidewall.

What is claimed is: 
     
         1 . A waveguide neural interface device comprising:
 a neural device configured for implanting in tissue, the neural device comprising an exterior neural device sidewall extending to a distal end portion of the neural device;   an array of electrode sites supported by a first face of the neural device sidewall, wherein the array of electrode sites are configured to electrically communicate with their surroundings and comprises at least one recording electrode site;   a waveguide extending along at least a portion of the neural device, the waveguide having a proximal end to receive light from a light source and a distal end to emit the light to illuminate targeted tissue adjacent to the at least one recording electrode site; and   a light redirecting element disposed at the distal end of the waveguide, the light redirecting element configured to redirect light traveling through the waveguide in a manner that avoids direct illumination of the at least one recording electrode site on the first face of the neural device sidewall.   
     
     
         2 . The waveguide neural interface device of  claim 1 , wherein the at least one recording electrode site is configured to sample illuminated tissue. 
     
     
         3 . The waveguide neural interface device of  claim 1 , wherein the waveguide is an optical fiber supported by the first face of the neural device sidewall. 
     
     
         4 . The waveguide neural interface device of  claim 3 , wherein the optical fiber include a beveled tip as the light redirecting element, the beveled tip having an angle that refracts emitted light away from the array of electrode sites. 
     
     
         5 . The waveguide neural interface device of  claim 1 , wherein the waveguide comprises:
 an inner waveguide core formed over the lower cladding material; and   an upper cladding material portion that partially covers the inner waveguide core.   
     
     
         6 . The waveguide neural interface device of  claim 5 , wherein the light redirecting element comprises an opening in the upper cladding material portion that exposes the inner waveguide core, wherein the opening is angled within respect to a longitudinal axis of the waveguide. 
     
     
         7 . The waveguide neural interface device of  claim 6 , wherein the opening in the upper cladding material portion that exposes the inner waveguide core exposes an edge of the inner waveguide core such that light is emitted from a side surface of the inner waveguide core and from a top surface of the inner waveguide core. 
     
     
         8 . The waveguide neural interface device of  claim 1 , wherein the light redirecting element includes a reflector disposed at the distal end of the waveguide. 
     
     
         9 . The waveguide neural interface device of  claim 8 , wherein the distal end of the waveguide is tapered towards the reflector. 
     
     
         10 . The waveguide neural interface device of  claim 9 , wherein a reflective surface of the reflector is parallel to the first face of the neural device sidewall and the waveguide directs light toward the reflector at an angle relative to the reflective surface. 
     
     
         11 . A waveguide neural interface device comprising:
 a neural device substrate having an elongate shape, the neural device substrate having a first face that is positioned opposite a second face;   an array of electrode sites disposed on the first face of the neural device substrate, wherein the array of electrode sites are configured to electrically communicate with their surroundings and comprises at least one recording electrode site; and   a waveguide extending along the second face of the neural device substrate, the waveguide having a proximal end to receive light from a light source and a distal end to emit the received light to illuminate targeted tissue adjacent to the at least one recording electrode site, wherein the distal end of the waveguide have a light directing feature that extends laterally beyond a lateral edge of the neural device substrate, the light redirecting feature configured to redirect the received light toward the first face of the neural device substrate and around the neural device substrate.   
     
     
         12 . The waveguide neural interface device of  claim 11 , wherein the light redirecting feature extends laterally beyond three sides of the neural device substrate. 
     
     
         13 . The waveguide neural interface device of  claim 11 , wherein the distal end of the waveguide extends beyond a distal end of the neural device substrate and the distal end of the waveguide includes an angled tip to facilitate insertion of the waveguide neural interface device into tissue. 
     
     
         14 . The waveguide neural interface device of  claim 11 , wherein a distal end of the neural device substrate includes an angled tip to facilitate insertion of the waveguide neural interface device into tissue. 
     
     
         15 . The waveguide neural interface device of  claim 14 , wherein a distal end of the waveguide includes an angled tip to facilitate insertion of the waveguide neural interface device into tissue. 
     
     
         16 . The waveguide neural interface device of  claim 11 , wherein the waveguide has a first thickness and the neural device substrate has a second thickness, the first thickness being greater than the second thickness such that the waveguide structurally supports the neural device substrate. 
     
     
         17 . The waveguide neural interface device of  claim 11 , wherein the waveguide comprises:
 an inner core;   a cladding layer surrounding the inner core, wherein a material of the inner core and a material of the cladding layer cooperate to provide internal reflection to the waveguide; and   an optically dissipating portion formed in the cladding layer to selectively emit the light toward the targeted tissue.   
     
     
         18 . The waveguide neural interface device of  claim 17 , wherein the optically dissipating portion comprises an opening formed in the cladding layer and a coating layer of a light dissipating material contacting the inner core. 
     
     
         19 . A waveguide fabrication process, the process comprising:
 depositing a sacrificial material layer onto a substrate;   depositing a lower cladding material layer onto the sacrificial material layer;   forming an inner waveguide core on the lower cladding material layer;   depositing an upper cladding material layer over the inner waveguide core, a portion of the upper cladding material layer contacting the lower cladding material layer; and   forming an aperture in the upper cladding material layer to provide an optically dissipating portion of a waveguide including the inner waveguide core so that light introduced into the waveguide is emitted from the aperture.   
     
     
         20 . The waveguide fabrication process of  claim 19 , further comprising:
 forming a coating layer over the upper cladding material layer and aperture; and   patterning the coating layer to remove at least a portion of the coating layer from over the upper cladding material layer.