| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide the convergence correction device for a projection video display device and it method that correct automatically a convergence according to video signals, the aspect ratios of which are 12.8:9 and 4:3. SOLUTION: This device consists of a system control signal 20 that discriminates as to whether an aspect ratio of a video signal is 12.8:9 or 4:3, produces a control signal according to the result of discrimination and provides an output of size information of the video signal, a main deflection circuit section 21 that generates a main deflection signal with respect to the video signal whose aspect ratio is 12.8:9 or 4:3, based on the control signal being an output of the system control section 20, an auxiliary deflection circuit section 22 that stores a convergence correction value with respect to the video signal whose aspect ratio is 12.8:9 or 4: 3 in advance and provides an output of the convergent correction signal with the convergence correction value corresponding to the size information of the video signal outputted from the system control section 20, plural wide cathode ray tubes 231-233 that deflect and display electron beams for R, G, B video signals in accordance with the output signals from the main deflection circuit section 21 and the automatically deflection circuit section 22, and a wide screen 234 on which the video images displayed on the wide cathode-ray tubes 231-233 with magnification through an optical section.</p> |
