| 摘要 |
PURPOSE:To inject electrical charge into a charge coupled device without the reduction of SN ratio and working range by a method wherein a d.c. gate is prepared between a sampling gate and a floating junction part in a CCD element. CONSTITUTION:A charge generated in an input diode 11 by the application of a signal voltage V1 is injected into the regions under d.c. gates 41, 42 applied with a reference voltage VR and into a floating junction 13 at on-time (t2) of sampling pulse phiS applied to a gate 12. When a gate 15 is made to be off state at time t3, a signal charge 43 is left at the floating junction 13, and coupling capacitance does not exist between the gate 12 and the junction 13 being shielded by the d.c. gate 41. Therefore, feed through component of pulse phiS at its rise time and fall time and noise in phiS does not add to the signal charge 43, and the deterioration of SN ratio of signal charge and the reduction of working range in a process of charge injection can be suppressed. The signal charge 43 is sent to a transfer gate 15 at the time t4. |
