ITE Ball Chart

1£® This Chart is used for strain measurement of a TV camera's geometric image. 2£® There are 158 double rings which are arranged in 14 rows and 17 columns. The vertical spacing is 1/14h and the horizontal spacing is 2/25h. 3£® The sizes of the double rings are stated as follows: (1)Outer rings ¡¡Outer circle of the ring¡¡Radius£º2/100h(2%) ¡¡Inner circle of the ring¡¡Radius£º1.5/100h(1.5%) (2)Inner rings ¡¡Outer circle of the ring¡¡Radius£º1/100h(1%) ¡¡Inner circle of the ring¡¡Radius£º0.5/100h(0.5%)