| 摘要 |
PURPOSE:To obtain a control circuit for high-voltage which is capable of proper control with a small size, high reliability and high accuracy, by detecting the volume of emitted light of a cathode-ray tube and then controlling the operation of a high- voltage generating circuit based on the result obtained by giving a prescribed operation to the output of the above-mentioned detection. CONSTITUTION:The output of an optical detector 1 attached to the cathode-ray tube CRT is applied to the arithmetic control part 3 via an amplifier 2 and then compared with the value obtained by giving a calculation to the current value given from the automatic beam limiter ABL. The output is then converted into e.g. the characteristic curve that is stored previously and through the arithmetic control part 3. Thus a high voltage is stabilized via the errordetecting transistor TR2. On the other hand, the correlation is examined previously between the luminous flux quantity and the X-ray quantity, and the control part 4 stores the limit of allowance for the correlation. Then the X-ray protector PC is actuated by the output of the part 4. In such way, a small-size and accurate high-voltage control circuit can be obtained with high reliability. |
