A metal sheet has a longitudinal direction and a width direction. The metal sheet has shapes in the width direction that are taken at different positions in the longitudinal direction of the metal sheet and differ from one another. Each of the shapes is an undulated shape including protrusions and depressions repeating in the width direction of the metal sheet. A length in the width direction of a surface of the metal sheet is a surface distance. A minimum value of surface distances at different positions in the longitudinal direction of the metal sheet is a minimum surface distance. A ratio of a difference between a surface distance and the minimum surface distance to the minimum surface distance is an elongation difference ratio in the width direction. A maximum value of elongation difference ratios is less than or equal to 2×10.sup.−5.

A metal sheet has a longitudinal direction and a width direction. The metal sheet has shapes in the width direction that are taken at different positions in the longitudinal direction of the metal sheet and differ from one another. Each of the shapes is an undulated shape including protrusions and depressions repeating in the width direction of the metal sheet. A length in the width direction of a surface of the metal sheet is a surface distance. A minimum value of surface distances at different positions in the longitudinal direction of the metal sheet is a minimum surface distance. A ratio of a difference between a surface distance and the minimum surface distance to the minimum surface distance is an elongation difference ratio in the width direction. A maximum value of elongation difference ratios is less than or equal to 2×10.sup.−5.

A method of fabricating a metal mask includes receiving a conductive substrate with a first surface, a second surface opposite to the first surface, a third surface connecting the first and second surfaces, and a fourth surface opposite to the third surface and connecting the first and second surfaces. The method further includes forming trenches in a direction from the first surface to the second surface and protrusions in the conductive substrate. The trenches and the protrusions are alternately arranged. The method further includes filling the trenches with an insulation material covering a first area of the protrusions, forming a metal layer on the conductive substrate overlying a second area different from the first area of the protrusions, removing the insulation material, and removing the conductive substrate. The metal layer becomes a metal mask with a three-dimensional structure including strip-shaped structures.

A mask and a method of manufacturing the same are disclosed. The method of manufacturing a mask includes forming a conductive layer on a pattern region and an auxiliary region around the pattern region of a substrate, placing the substrate including the conductive layer in a plating bath, forming a plating layer on the conductive layer, and separating the substrate and the conductive layer from the plating layer.

A mask and a method of manufacturing the same are disclosed. The method of manufacturing a mask includes forming a conductive layer on a pattern region and an auxiliary region around the pattern region of a substrate, placing the substrate including the conductive layer in a plating bath, forming a plating layer on the conductive layer, and separating the substrate and the conductive layer from the plating layer.

A method of manufacturing a metal mask includes providing a growth substrate with a conductive surface. Then, a cover pattern is formed on the conductive surface, which has at least one opening and an insulated surface touching the conductive surface. Next, using the cover pattern as a mask, a first electroforming is performed to form a mold part on the conductive surface. The mold part fills the opening and has a conductive pattern surface touching the conductive surface. The conductive pattern surface is flush with the insulated surface. After the first electroforming, the growth substrate is removed, while the cover pattern and the mold part are reserved. After removing the growth substrate, a second electroforming is performed to the conductive pattern surface of the mold part to form a metal pattern. Afterwards, the mold part and the cover pattern are removed from the metal pattern.

A method of manufacturing a metal mask includes providing a growth substrate with a conductive surface. Then, a cover pattern is formed on the conductive surface, which has at least one opening and an insulated surface touching the conductive surface. Next, using the cover pattern as a mask, a first electroforming is performed to form a mold part on the conductive surface. The mold part fills the opening and has a conductive pattern surface touching the conductive surface. The conductive pattern surface is flush with the insulated surface. After the first electroforming, the growth substrate is removed, while the cover pattern and the mold part are reserved. After removing the growth substrate, a second electroforming is performed to the conductive pattern surface of the mold part to form a metal pattern. Afterwards, the mold part and the cover pattern are removed from the metal pattern.

Disclosed is a method for producing a mold obtained by providing a monolithic optical lens element having at least a finished optical surface, the monolithic optical lens element being made of an organic material. The method includes: coating the finished optical surface with an electrically conductive material; depositing on the coated finished optical surface a layer of metal to produce a metal element having a surface which is a replication of the finished optical surface; and separating the monolithic optical lens element and the metal element, the metal element forming a mold replicating the finished optical surface of the monolithic optical lens element.

A method of fabricating a metal mask includes receiving a conductive substrate with a first surface, a second surface opposite to the first surface, a third surface connecting the first and second surfaces, and a fourth surface opposite to the third surface and connecting the first and second surfaces. The method further includes forming trenches in a direction from the first surface to the second surface and protrusions in the conductive substrate. The trenches and the protrusions are alternately arranged. The method further includes filling the trenches with an insulation material covering a first area of the protrusions, forming a metal layer on the conductive substrate overlying a second area different from the first area of the protrusions, removing the insulation material, and removing the conductive substrate. The metal layer becomes a metal mask with a three-dimensional structure including strip-shaped structures.

According to an embodiment of the present invention, a method for producing a duplicate of a nano-pattern texture of a surface of an object through electroforming using an imprint mold comprises selecting the object having the nano-pattern texture, disposing the selected object and pretreating a surface of the object by washing, drying and then forming a nano-thin film thereto to block transfer of impurities, metallizing a surface of the plastic mold through, e.g., vapor deposition, spraying, and wet silver mirror reaction, and performing a first electroforming of the surface of the plastic mold, and repeating to thus manufacture a plurality of metal module master molds.