Filter for use in a cartridge for the preparation of a beverage

A filter for preparation of extracted beverages comprising a single planar sheet of material including two planar surfaces having a plurality of uniformly distributed openings extending through the sheet and having a plurality of nipples, equal in number to the number of openings, projecting from and out of at least one of the planar surfaces to a nipple end disposed away from the planar surface from which the nipple projects, wherein each nipple is associated with one of the openings through the sheet, wherein each opening extends through each nipple, wherein each opening at the end of each nipple forms a minor base of an opening shape, wherein each opening at the other planar surface forms a major base of the opening shape and wherein the opening shape defined about the openings by the sheet and each nipple is a shape selected from a group of shapes consisting of

• (i) a frustoconical shape wherein the minor base opening has a diameter of between 0.1 m and 0.3 mm and the major base opening has a diameter of between 0.2 mm and 0.5 mm
• (ii) a frustopyramidal shape wherein a diagonal of a square of the minor base opening is between 0.1 mm and 0.3 mm and wherein a diagonal of a square of the major base opening is between 0.2 mm and 0.5 mm;
• and
• (iii) a shape in a form of an equilateral truncated tetrahedron wherein sides of a triangle of the minor base opening define an opening of between 0.1 mm and 0.3 mm and wherein sides of the major base opening define an opening of between 0.2 mm and 0.5 mm.