Apparatus for inspecting defect of rubbing cloth and rubbing apparatus with the same

A rubbing apparatus having an apparatus for inspecting a rubbing cloth for a defect, comprising:

• a table for supporting a substrate;
• a rubbing roll rotatably installed on the top surface of the table, a rubbing cloth being wrapped round the outer circumference of the rubbing roll;
• and
• a apparatus for inspecting the rubbing cloth installed on the table
• wherein the apparatus for inspecting the rubbing cloth comprises:
• a housing surrounding the periphery of the rubbing cloth;
• a transfer unit connected to the upper portion of the housing for transferring the housing along a length direction of a rubbing roll, wherein the transfer unit comprises rails installed on a table, wheels contacting the rails and a wheel driving motor for driving the wheels, wherein when the rubbing roll is rotated for inspecting defect of the rubbing cloth, the housing is transferred by the transfer unit at the same time, and when the wheels are rotated by the rotation of the driving motor, the wheels move along the rails to transfer the housing;
• an illumination unit installed at one side in the housing for illuminating the rubbing cloth;
• and a camera unit installed at the other side in the housing to correspond to the illumination unit on the basis of the rubbing roll, wherein the camera unit comprises an upper camera for photographing the top end of the rubbing cloth, a lower camera for photographing the bottom end of the rubbing cloth and an intermediate camera for photographing the intermediate portion of the rubbing cloth.

A method for inspecting defect of a rubbing cloth, comprising:

• preparing an apparatus for inspecting a rubbing cloth and a rubbing apparatus;
• providing the rubbing cloth;
• illuminating the rubbing cloth by using an illumination unit disposed at the apparatus for inspecting the rubbing cloth, wherein the apparatus for inspecting the rubbing cloth comprises a housing surrounding the periphery of the rubbing cloth;
• a transfer unit connected to the upper portion of the housing for transferring the housing along a length direction of a rubbing roll, wherein the transfer unit comprises rails installed on a table, wheels contacting the rails and a wheel driving motor for driving the wheels, and wherein when the rubbing roll is rotated for inspecting defect of the rubbing cloth, the housing is transferred by the transfer unit at the same time, and when the wheels are rotated by the rotation of the driving motor, the wheels move along the rails to transfer the housing;
• measuring the thickness of the rubbing cloth by using a camera unit disposed at
• the apparatus for inspecting the rubbing cloth, wherein measuring the thickness of the rubbing cloth is performed by measuring the thickness from one end to another end of the rubbing cloth at an upper of a rubbing roll by using an upper camera disposed at the apparatus for inspecting the rubbing cloth, and measuring the thickness from one end to another end of the rubbing cloth at a bottom of a rubbing roll by using a lower camera;
• and
• detecting the thickness of the rubbing cloth by subtracting a rubbing cloth value from the values measured by the upper camera and the lower camera.

A method for inspecting defect of a rubbing cloth, comprising:

• preparing an apparatus for inspecting a rubbing cloth and a rubbing apparatus;
• providing the rubbing cloth;
• illuminating the rubbing cloth by using an illumination unit disposed at the apparatus for inspecting the rubbing cloth;
• measuring the thickness of the rubbing cloth by measuring the thickness from one end to another end of the rubbing cloth at an upper of a rubbing roll by using an upper camera disposed at the apparatus for inspecting the rubbing cloth, and measuring the thickness from one end to another end of the rubbing cloth at a bottom of a rubbing roll by using a lower camera, wherein the apparatus for inspecting the rubbing cloth comprises a housing surrounding the periphery of the rubbing cloth;
• a transfer unit connected to the upper portion of the housing for transferring the housing along a length direction of a rubbing roll, wherein the transfer unit comprises rails installed on a table, wheels contacting the rails and a wheel driving motor for driving the whee1s, and wherein when the rubbing roll is rotated for inspecting defect of the rubbing cloth, the housing is transferred by the transfer unit at the same time, and when the wheels are rotated by the rotation of the driving motor, the wheels move along the rails to transfer the housing;
• an illumination unit installed at one side in the housing for illuminating the rubbing cloth;
• and a camera unit installed at the other side in the housing to correspond to the illumination unit on the basis of the rubbing roll, wherein the camera unit comprises an upper camera for photographing the top end of the rubbing cloth, a lower camera for photographing the bottom end of the rubbing cloth and an intermediate camera for photographing the intermediate portion of the rubbing cloth;
• and
• detecting a loosened part from the rubbing cloth according to the thickness of the rubbing cloth.

A method for inspecting defect of a rubbing cloth, comprising:

• preparing an apparatus for inspecting a rubbing cloth and a rubbing apparatus;
• providing the rubbing cloth;
• illuminating the rubbing cloth by using an illumination unit disposed at the apparatus for inspecting the rubbing cloth, wherein the apparatus for inspecting the rubbing cloth comprises a housing surrounding the periphery of the rubbing cloth;
• a transfer unit connected to the upper portion of the housing for transferring the housing along a length direction of a rubbing roll, wherein the transfer unit comprises rails installed on a table, wheels contacting the rails and a wheel driving motor for driving the wheels, and wherein when the rubbing roll is rotated for inspecting defect of the rubbing cloth, the housing is transferred by the transfer unit at the same time, and when the wheels are rotated by the rotation of the driving motor, the wheels move along the rails to transfer the housing;
• an illumination unit installed at one side in the housing for illuminating the rubbing cloth;
• and a camera unit installed at the other side in the housing to correspond to the illumination unit on the basis of the rubbing roll, wherein the camera unit comprises an upper camera for photographing the top end of the rubbing cloth, a lower camera for photographing the bottom end of the rubbing cloth and an intermediate camera for photographing the intermediate portion of the rubbing cloth;
• and
• detecting foreign objects and substances sticking to the rubbing cloth in every predetermined section, and detecting the portion stained with foreign objects and substances due to cloth scouring on the basis of the gray scale, by using the intermediate camera disposed at the apparatus for inspecting the rubbing cloth, wherein the intermediate camera photographs the intermediate portion of the rubbing cloth.