GB/T 37900-2019 specifies the test principles, equipment, procedures, and result calculations for the hardness and fracture toughness of ultra-thin glass using the small-load Vickers hardness indentation method with applied loads ranging from 1.961 N to 49.03 N. It is applicable to hardness testing of glass with thicknesses of 0.1 mm to 1.1 mm and fracture toughness testing of glass with thicknesses of 0.3 mm to 1.1 mm. The method involves indenting the specimen with a diamond indenter and measuring the indentation diagonals and crack propagation lengths to calculate the performance parameters. Relevant testing instruments include a small-load Vickers hardness tester (with a test force resolution not lower than 0.01 N), a reading microscope with a magnification not less than 50×, and a rigid support block paired with a high-precision measurement system to ensure test accuracy.