Method for manufacturing glass sheet, and glass sheet and glass sheet assembly

A method of manufacturing a glass sheet having a through hole, the method comprising:

• a first step of preparing a glass sheet;
• and
• a second step of forming, in the glass sheet, a through hole gradually widened toward at least one side of a sheet thickness direction,
• wherein the first step comprises:
• preparing a glass sheet for which a sheet thickness variation range ΔT of the glass sheet satisfies the following relationship when the through hole in the second step is gradually widened toward only one side of the sheet thickness direction:
• ΔT≤(D×A/tan θ)/200, or
• preparing a glass sheet for which the sheet thickness variation range ΔT of the glass sheet satisfies the following relationship when the through hole in the second step is gradually widened from a middle portion in the sheet thickness direction toward both of one side and another side of the sheet thickness direction:
• ΔT≤(D×A/tan θ)/100
• provided that θ represents an inclination angle of an inner wall surface of the through hole with respect to the sheet thickness direction;
• D represents a minimum hole width of the through hole;
• and an allowable variation range of the minimum hole width D is represented by A % of the minimum hole width D.