3D printed graded refractive index device

A GRIN (graded-index) device comprising:

• i) a first phase comprising at least one polymer formed by vat polymerization of a substantially homogeneous mixture of a monomer and at least one first component;
• ii) a second phase comprising the at least one first component;
• and,
• iii) an interface between the first phase and the second phase, wherein the interface has a uniform concentration gradient of the at least one first component, whereby the concentration of the at least one first component decreases with distance away from the second phase towards the first phase,
• whereby as the vat polymerization occurs, the at least one first component diffuses away from a focused region of polymerization in the mixture thereby forming in the GRIN device the interface having the uniform concentration gradient of the at least one first component,
• wherein the at least one first component comprises at least one functional component, at least one functional precursor component, or combinations thereof, and
• wherein the device is a functional device, a functional precursor device, or a combination of a functional and functional precursor device.