Broadband, freeform focusing micro optics for side-viewing imaging catheters

A method for manufacturing a side-viewing micro optic for a catheter, comprising:

• creating one or more curved surfaces in a silica wafer, wherein the one or more curved surfaces have a geometry suitable to shape an internal optical beam by reflection;
• depositing a reflective coating on the silica wafer to provide reflectivity, thereby converting the one or more curved surfaces into one or more internal freeform reflective surfaces;
• cutting the silica wafer to obtain one or more micro-optic elements, which are configured to receive an incoming optical beam along a rotational axis of the catheter, wherein each micro-optic element includes a freeform reflective internal surface to reflect the incoming optical beam in a substantially orthogonal direction from the optical axis toward a target location, and wherein internal reflective-freeform reflective internal surface is shaped to focus the light incoming optical beam so that a resulting beam shape at the target location has substantially equal axial and transaxial dimensions;
• and
• wherein creating the one or more curved surfaces involves creating a microlens array comprising a large number of curved surfaces organized in a rectangular pattern on the silica wafer;
• and
• wherein the cutting of the silica wafer is performed using a dicing saw by:
• mounting the coated silica wafer on a silicon wafer using mounting media,
• cutting the microlens array along a vertical direction of the microlens array to create individual strips of microlenses,
• removing each microlens strip from the silicon wafer by heating the mounting media,
• positioning and securing each microlens strip so that a side of the microlens strip is attached to a second silicon wafer using mounting media,
• using a dicing saw to cut each microlens strip into individual microlenses, and
• performing a trimming operation on each microlens.

A method for manufacturing a side-viewing micro optic for a catheter, comprising:

• creating one or more curved surfaces in a silica wafer, wherein the one or more curved surfaces have a geometry suitable to shape an internal optical beam by reflection;
• depositing a reflective coating on the silica wafer to provide reflectivity, thereby converting the one or more curved surfaces into one or more internal freeform reflective surfaces;
• cutting the silica wafer to obtain one or more micro-optic elements, which are configured to receive an incoming optical beam along a rotational axis of the catheter, wherein each micro-optic element includes a freeform reflective internal surface to reflect the incoming optical beam in a substantially orthogonal direction from the optical axis toward a target location, and wherein the freeform reflective internal surface is shaped to focus the incoming optical beam so that a resulting beam shape at the target location has substantially equal axial and transaxial dimensions;
• and
• wherein the cutting of the silica wafer is performed in a single operation by tilting a cutting plane.