IEC 63181-2:2020 specifies measuring methods for LCD multi-screen display terminals. To evaluate the characteristics of LCD multi-screen display terminals, the following measurement items are specified: – gap (physical, optical): detailed splicing precision; – splicing deviation: splicing accuracy of active areas of LCD splicing screen; – installation deviation: the flatness of terminal surfaces in vertical and horizontal directions; – luminance uniformity: luminance uniformity of adjacent LCD units; – chromatic uniformity: chromatic uniformity of adjacent LCD units.