Grating Light Modulator (GLM) based on Micro-Electro-Mechanical Systems (MEMS) is applied in projection display.Operating principle of GLM is introduced in the paper.Critical factors influencing the performance of passive matrix addressing for GLM are analyzed in detail.Both the response frequency and the driving voltage are relative to the elastic coefficient of GLM.If the elastic coefficient is larger,both response frequency and driving voltage are larger.It is indicated by analysis that in a m×n array when an all-selected pixel is actuated by a voltage V0,the voltages of half-selected pixel in row and column are respectively V0(m-1)/(m+n-1) and V0(n-1)/(m+n-1),and non-selected pixels voltage is V0/(m+n-1).Finally,the operating voltage and the pull-in voltage are respectively 7.8V and 8.5V measured by the experiment,and these experimental values are very approximate to the theoretical values.When GLM is actuated by a 7.8V square-wave voltage with lkHz frequency,the rising-edge time and the falling-edge time are respectively about 46.59μs and 44.77μs.The experiments indicate that the response frequency of GLM is about 5kHz.And,the other experiment validates the correctness of crosstalk in a 16×16 GLM array.These experiments provide a theoretical basis for improving the driver of GLM.