How to use fabric warp and weft density mirror?

First, you need to figure out what is fabric density? Fabric density refers to the number of yarns per unit area of the fabric. The longitude direction is called warp density, and the latitude direction is called weft density. The current fabric density in China can be expressed in metric system and British system. The metric system refers to the number of yarns within 10 cm of the fabric. Imperial refers to the number of yarns within 1 inch of a fabric. The two can be converted, calculated as 1 inch = 2.54 cm. According to the above definition, the densitometer is generally designed as a square magnifying glass in inches or centimeters. For example, the density above you is 30 pieces 78 * 65, which means that there are 78 warp yarns and 65 weft yarns in 1 square inch of fabric. Written Jingmi: 78 pieces / inch; Weft density: 65 pieces / inch; It's 78 * 65. For example, the upper fabric is expressed in the British system (for example, the British system is a unified unit). In fact, it depends on whether the upper fabric is expressed in the British system or in the British system