Friction roller and method for using the same

1. An apparatus for rubbing a surface of a substrate, comprising:

a friction roller comprising:

an inner cylinder, and

a pattern-variable module wrapped outside the inner cylinder, the pattern-variable module comprising a deformation layer comprising a plurality of deformation units;

a controller connected with the pattern-variable module; and

a detection machine connected with the controller,

wherein the detection machine is configured to, responsive to an instruction from the controller, acquire an optical image of the surface of the substrate, obtain step information of the surface based on the acquired image, and send the obtained step information to the controller, and

wherein the controller is configured to control at least one of the deformation units to deform in a radial thickness direction according to the step information.

2. The apparatus as claimed in claim 1 ,

wherein the friction roller further comprises a deformation perception layer comprising a plurality of perception units corresponding to the plurality of deformation units one to one, the deformation layer and the deformation perception layer successively wrapped outside the inner cylinder, and

wherein the controller is further connected with the deformation perception layer and configured to acquire pressure sensing signals generated by the plurality of perception units according to magnitudes of undergone pressures and control the at least one of the deformation units to deform according to the pressure sensing signals, the pressure sensing signals being indicative of the step information of the surface of the substrate.

3. The apparatus as claimed in claim 2 , wherein each of the plurality of perception units is provided with a first electrode, a second electrode, and insulation substance located between the first electrode and the second electrode, the first electrode and the second electrode forming a capacitor, and wherein the perception unit is configured to generate the pressure sensing signal by producing a corresponding number of electric charges that cause a change in the number of the electric charges stored in the capacitor after undergoing a pressure.

4. The apparatus as claimed in claim 3 , wherein the insulation substance is piezoelectric ceramic.

5. The apparatus as claimed in claim 3 , wherein the pattern-variable module is made from an inverse piezoelectric material, and wherein the controller is configured to control the at least one of the deformation units to deform by applying an electric signal to the inverse piezoelectric material to cause a change in a thickness of the inverse piezoelectric material.

6. The apparatus as claimed in claim 2 , wherein the plurality of perception units are made from pressure-sensitive conductive rubber.

7. The apparatus as claimed in claim 2 , wherein the pattern-variable module is made from an inverse piezoelectric material, and wherein the controller is configured to control the at least one of the deformation units to deform by applying an electric signal to the inverse piezoelectric material to cause a change in a thickness of the inverse piezoelectric material.

8. The apparatus as claimed in claim 1 , wherein the friction roller further comprises friction cloth for being wrapped outside the pattern-variable module during a rubbing operation.

9. The apparatus as claimed in claim 1 , wherein the pattern-variable module is made from an inverse piezoelectric material, and wherein the controller is configured to control the at least one of the deformation units to deform by applying an electric signal to the inverse piezoelectric material to cause a change in a thickness of the inverse piezoelectric material.

10. The apparatus as claimed in claim 9 , wherein an absolute value of an amount of change in the thickness is greater than zero and less than or equal to a height of a maximum step of the surface of the substrate.

11. A method for rubbing a surface of a substrate using the apparatus as claimed in claim 1 , the method comprising:

acquiring, by the detection machine, an optical image of the surface of the substrate;

obtaining, by the detection machine, step information of the surface based on the acquired image; and

controlling, by the controller, at least one of the deformation units to deform in the radial thickness direction according to the obtained step information.

12. The method as claimed in claim 11 ,

wherein the friction roller further comprises a deformation perception layer comprising a plurality of perception units corresponding to the plurality of deformation units one to one, the deformation layer and the deformation perception layer successively wrapped outside the inner cylinder, the controller connected with the deformation perception layer,

wherein before controlling by the controller the at least one of the deformation units to deform, the method further comprises: acquiring by the controller pressure sensing signals generated by the plurality of perception units according to magnitudes of undergone pressures, and

wherein controlling by the controller the at least one of the deformation units to deform comprises: controlling by the controller the at least one of the deformation units to deform according to the pressure sensing signals, the pressure sensing signals being indicative of the step information of the surface of the substrate.