| 摘要 |
PURPOSE:To make easy the adjustment for electron rays to go into the electronic optical axis of an object lens by enabling the deflection signal synchronized to the scan signal of a scanning coil to be inputted to an alignment coil at the time of adjustment. CONSTITUTION:A scanning type electron ray device is made up of a scanning coil 25, an object lens 24, and an alignment coil 21 used for adjustment of the direction of electron rays coming in. At this time a drive circuit 22, which is to drive the alignment coil 21, is formed in combination with an adding machine 23 whih has a function to add a voltage obtained from a high-voltages signal generation circuit 38 via alignment adjust resistors RVx, RVy, to a voltage obtained from a magnification switching circuit 28 via switches Six, Siy and to input the result to the drive circuit 22. Therefore, based on the figure appearing on a CRT display 30, the alignment coil 21 can be adjusted so that the electron rays go into the electronic optical axis of the object lens 24, and the adjustment can be made very easily. |
