Apparatus and method for holding a green sheet and system and method for inspecting a green sheet

A sheet holding apparatus, comprising:

• a first member having a first porous surface for supporting a first edge of the sheet, the first porous surface being fluidly connected to a vacuum source;
• a second member moveable relative to the first member, the second member having a second porous surface for supporting a second edge of the sheet, the second porous surface being fluidly connected to a vacuum source;
• a third member having a third porous surface for supporting a third edge of the sheet, the third porous surface being fluidly connected to a vacuum source;
• a fourth member moveable relative to the third member, the fourth member having a fourth porous surface for supporting a fourth edge of the sheet, the fourth porous surface being fluidly connected to a vacuum source;
• and
• a forcing mechanism including a housing, the housing attached to the first member, the second member, the third member, and the fourth member, the forcing mechanism being capable of forcing the second member away from the first member, and the forcing mechanism being capable of forcing the fourth member away from the third member, whereby the green sheet is flattened.

A method of holding a screened green sheet, comprising the steps of:

• providing a screened green sheet having a first edge and an opposing second edge;
• securing the first edge to a first member;
• securing the second edge to a second member;
• and
• applying a force to the second member, such that the second member is forced away from the first member and such that the first edge and the second edge are pulled outwardly, thereby flattening the green sheet.

A method of inspecting a screened pattern on a green sheet, comprising:

• providing a green sheet having a first edge and an opposing second edge, a third edge and an opposing fourth edge, and a first side and an opposing second side, the green sheet having a pattern screened thereon;
• and
• securing the first edge to a first member;
• securing the third edge to a third member;
• securing the second edge to a second member;
• securing the fourth edge to a fourth member;
• applying a force to the second member, such that the second member is forced away from the first member and such that the first edge and the second edge are pulled away from each other, thereby flattening the green sheet;
• applying a force to the fourth member, such that the fourth member is forced away from the third member, and such that the third edge and the fourth edge are pulled away from each other, thereby flattening the green sheet;
• directing a light onto the green sheet;
• and
• detecting the light as it emerges or is reflected from the green sheet.