Optical fiber with an acoustically sensitive fiber Bragg grating and ultrasound sensor including the same

An ultrasound sensor, comprising:

• at least one optical fiber embedded in a polymer layer;
• a fiber Bragg grating and a reflector formed in an optical fiber core of the at least one optical fiber, wherein the fiber Bragg grating and the reflector are spaced apart from one another;
• a cladding material disposed on and surrounding at least a portion of the optical fiber core, wherein the cladding material has at least one material property associated therewith, the at least one material property being selected from the group consisting of a smaller Young's modulus than a Young's modulus of the optical fiber core, a larger photo-elastic coefficient than a photo-elastic coefficient of the optical fiber core, and combinations thereof;
• a backing layer;
• and
• an acoustic matching layer,
• wherein the polymer layer and the at least one optical fiber are sandwiched between the backing layer and the acoustic matching layer.

An optical chip with an acoustically sensitive fiber Bragg grating, comprising:

• a substrate;
• an optically transparent layer formed on the substrate, wherein the optically transparent layer defines a core region, and wherein a fiber Bragg grating and a reflector are formed in the core region, the fiber Bragg grating and the reflector being spaced apart from one another;
• and
• a cladding material disposed on and surrounding at least a portion of the core region such that the core region is at least partially sandwiched between the cladding material and the substrate, wherein the cladding material has at least one material property associated therewith, the at least one material property being selected from the group consisting of a smaller Young's modulus than a Young's modulus of the core region, a larger photo-elastic coefficient than a photo-elastic coefficient of the core region, and combinations thereof.