| 摘要 |
PURPOSE:To achieve safe operational view by setting the cross angle between the polarization axes of polarization plates fixed respectively to the light or its front face and within the view of driver seat within predetermined range thereby lowering the permeability of light into the view. CONSTITUTION:A polarization plate 3 having the polarization axis 4 set in the direction of 0 deg. is arranged in front of a light 1 for irradiating the light L while a polarization plate 5 having the polarization axis 4 crossable with random angle is provided in the rear to be viewed from the rear through eyes. The crossing angle is made variable in the range of 60-120 deg.. The permeability of 48% for the crossing angle of 0 deg. can be reduced as the crossing angle increases upto 17% for the crossing angle of 90 deg.. When fixing one polarization plate 3 to the light 1 in tunnel or highway light 2 while another polarization plate 5 to the front glass of car, safe operational view can be achieved. |
