PURPOSE: To obtain correct observation information on a liquid crystal display element to be tested by placing the polarizing plate on the side of a camera near and in front of the camera lens or placing the plate between the lens and the element to be photographed.
CONSTITUTION: A TN type liquid crystal element 5 on which a polarizing plate is not yet pasted on is irradiated by a light 3 that is not polarized from the side of a TV camera 1, and the light passing through the element 5 is reflected with a polarizing plate 6 and a reflecting plate 7, so that the reflected light again passes the element 5. By the reflected light the liquid crystal element 5 is photographed on the TV camera 1, and test is performed based on the electric signal thus obtained. With this arrangement no shadow occurs on the reflecting plate 7 and the reflected light from it is polarized through the polarizing plate 6 and irradiates the liquid crystal element 5 from underneath and when the reflected light reaches the polarizing plate 9, it is detected whether or not the polarizing direction of the light has rotated through the liquid crystal element 5.
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