| 摘要 |
PURPOSE:To judge the rate of error with high precision by measuring the distance between a graduation and pointer and the distance among unit graduations and calculating the ratio of error by using image signal, horizontal and vertical synchronous pulses of a photographing device. CONSTITUTION:It is assumed that a pointer 2 is supposed to point a graduation 3 but lies between the graduations 3 and 4. The distances la, lb and lc of the centers of the graduations 3 and 4 and the pointer 2 from the left end of the photographed picture are calculated by distance calculating devices 18, 48 and 52 by using horizontal synchronous pulse 10, vertical synchronous pulse 12 and image signal 14 that are drawn out from the composition photo-image signal 7 of a photographing device 6 by means of a synchronous separator 8, and at a subtraction section 60 the subtraction (lc-la) is carried out to calculate the distance D between the graduations 3 and 4, and at the same time the subtraction (lb-la) is carried out at a subtraction section 62 to calculate the distance (d) between the graduation 3 and the pointer 2. The rate of error is obtained by carrying out the division ddivided by D at a division section 64. |
