Window for display apparatus, manufacturing method thereof, and manufacturing method of display apparatus

A window for a display apparatus comprising:

• a foldable part bent along a first direction;
• and
• a flat part adjacent to the foldable part,
• wherein the foldable part comprises a groove surface providing a groove having a plurality of radii of curvature defined in a plane perpendicular to the first direction, the groove surface comprises one end contacting the flat part, an other end contacting the flat part and facing the one end, and an internal point between the one end and the other end, and each of the one end, the other end and the internal point has a minimum radius of curvature among the plurality of radii of curvature, and
• a width of the groove surface in a second direction intersecting the first direction is defined as L1, the maximum depth of the groove is defined as d1, a thickness of the flat part is defined as h1, and the minimum radius of curvature is defined as RR, wherein
• RR is 2 m to 10 m inclusive,
• d1 is 0.01 mm to 0.05 mm inclusive,
• RR×(d1/L12) is 0.08 to 0.12 inclusive, and
• RR×(d1/L1/h1) is 10 to 50 inclusive.