Patent ID: 11953707
Assignee: PURDUE RESEARCH FOUNDATION
Field: Other special machines (Mechanical engineering)
Classification: CPC G  B | IPC B  G

Claim 14:
15. An angular movement sensing system, comprising:
a first multi-layer lens configured to be mounted on a first object, wherein light incident on the first multi-layer lens is configured to diffract;
a second multi-layer lens configured to be mounted on a second object, wherein angular movement of the first object with respect to the second object is to be measured, and wherein light incident on the second multi-layer lens is configured to diffract, each of the first multi-layer lens and the second multi-layer lens comprising
a plurality of dual-layer structures staked on top of one-another, wherein each dual-layer Ri of the plurality of dual-layers includes i) a first curable material having a height of ZLi cured at a predetermined curing level CA, and ii) a second curable material having a height of Zgi cured at a predetermined curing level CB;

a light source configured to be shone on the first multi-layer lens such that the first multi-layer diffracted light is incident on the second multi-layer lens;
a plurality of light sensors a distance away from the second multi-layer lens and configured to sense the first multi-layer diffracted light and the second multi-layer diffracted light; and
a data-processing system configured to
receive signals from the plurality of light sensors corresponding to the first multi-layer diffracted light and the second multi-layer diffracted light, and
determine angular relationship between the first multi-layer diffracted light and the second multi-layer diffracted light to thereby determine the rotational relationship between the first multi-layer lens and the second multi-layer lens.