| 摘要 |
PROBLEM TO BE SOLVED: To provide a video projection display device that conducts sensor signal processings for automatic convergence. SOLUTION: A screen image memory device of the projection display device exposed under unnecessary illumination is placed adjacent to an edge of a screen (700) and includes photosensors (S1-S8) to generate an output signal (Ii11) consisting of a 1st component responding to the emission, due to a projected image and of a 2nd component (Vinf), responding to the emission due to the unnecessary illuminance. A filter (C3, C4, R27, R28), connected to the photo sensors, applies filtering to the output signal (Ii11) to pass the 1st component of the output signal (Ii11) and attenuate the amplitude of the 2nd component (Vinf). |
