The requirements for the display quality of the client's screen are becoming stricter and newer problems have been discovered. Our company has discovered a new type of streak defects: when blinking or shaking your head, you will find vertical stripes on the display, but you can't see the defects when staring at the screen. This shaking head pattern is found in many products. In this study, we selected the G127 screen and adjusted the Vcom of the 6.47‐inch A‐si screen to different degrees to reproduce the bad head‐shaking pattern. Observing the visual effects of the experimental screen, we found that the greater the deviation of the Vcom, the more serious the head‐shaking phenomenon. The brightness test of the screen with the shaking head pattern shows that as the degree of the shaking head pattern becomes heavier, the brightness difference between adjacent columns is larger. It can be seen that the minimum brightness difference of the shaking head pattern is 0.108nit.