Surface shape measuring device

1. A surface shape measuring device, comprising:

a substrate having a flexible polymer material deformable by contact with an external object;

an electrode portion including at least one electrode pattern, the electrode pattern extending on the substrate and having a conductive polymer material;

a coating layer on the substrate to cover the electrode pattern and having a flexible polymer material deformable by contact with the external object; and

a detector electrically connected to the electrode pattern and configured to detect a change in a physical quantity of the electrode pattern generated by at least one of a deformation of the substrate and the coating layer by the external object applied thereto,

wherein the substrate or the coating layer has a surface roughness greater than a surface of the external object so that the surface shape measuring device makes a conformal contact with the surface of the external object, and

the detector is configured to detect the change in the physical quantity of the electrode pattern depending on a shape deformation of the surface of the external object in a state where the substrate or the coating layer is conformally attached to the external object.

2. The device of claim 1 , wherein the electrode portion comprises a first electrode pattern and a second electrode pattern spaced apart from each other.

3. The device of claim 2 , wherein the detector is configured to detect capacitance between the first electrode pattern and the second electrode pattern.

4. The device of claim 2 , wherein the first and second electrode patterns extend in a spiral.

5. The device of claim 4 , wherein a spacing distance between the first and second electrode patterns remains constant as each of the first and second electrode patterns revolves around the central point.

6. The device of claim 4 , wherein a spacing distance between the first and second electrode patterns is changed as each of the first and second electrode patterns revolves around the central point.

7. The device of claim 1 , wherein the electrode pattern extends in a serpentine shape.

8. The device of claim 7 , wherein the detector detects a resistance of the electrode pattern.

9. The device of claim 7 , wherein the substrate or the coating layer further comprises a protrusion on a surface thereof to contact with the surface of the external object.

10. The device of claim 1 , wherein the electrode portion comprises a plurality of electrode patterns arranged in a matrix shape.

11. The device of claim 1 , further comprising:

a calculator connected to the detector, the calculator configured to calculate a variation in a surface shape of at least one of the deformation of the substrate and the coating layer based on the detected change in the physical quantity.