盲点是在视网膜上，视神经穿出眼球的地方。这里没有感光细胞，物体的物象落在此点不能引起视觉。一般测试盲点的方法是闭上左眼，用右眼注视纸上的“十”字，然后移动白纸，以看不到纸上的圆圈来测定。 本实验对此进行了改进，以黑板代替纸，以教师自己代替纸上的圆圈，可以结 The blind spot is on the retina where the optic nerve pierces the eye. There is no photoreceptor cell here, and the object’s image falls on this point and cannot cause vision. The general method for testing blind spots is to close the left eye, look at the “ten” on the paper with the right eye, and then move the white paper to determine the circles on the paper. This experiment has been improved to use blackboard instead of paper to replace the circle on the paper itself.