Patent ID: 8059274

Claim:
An optical sensor that provides lateral viewing while maintaining light polarization, the sensor comprising: an endovascular catheter comprising a proximal end and a distal end; at least one waveguide including a distal end and a proximal end, wherein the proximal end of the waveguide is coincident near the proximal end of the endovascular catheter, the distal end of the waveguide is coincident at a point near the distal end of the endovascular catheter, and the waveguide is positioned within the endovascular catheter; and at least one refractive optical element positioned within the endovascular catheter near the distal end of the waveguide, wherein the refractive optical element is configured to refract light received from the distal end of the waveguide laterally from the endovascular catheter while maintaining the polarization state of the light, and wherein the at least one refractive optical element and the waveguide are configured such that the polarization state of light loses less than 40% of the light's polarization.