| 摘要 |
PURPOSE:To obtain a compact cathode-ray tube device for projection, which has no parallaxes and can be easily controlled, by performing a projection by use of a simple projection lens structure after making pictures to correspond to each other by means of fluorescent screens located on the projection optical axis by taking advantage of concave mirrors. CONSTITUTION:The projection optical axes of cathode-ray tubes 1-3, the angles of the central axes of concave mirrors 11 and 14, and the distances between the cathode-ray tubes 1-3, and a projection lens structure 15 and the mirrors 11 and 14 are adjusted so that the centers of the pictures of the fluorescent screens of the side cathode-ray tubes 1 and 3 correspond to the center of the picture of the fluorescent screen of the central cahode-ray tube 2 by means of the mirrors 11 and 14, and so that the sizes of the above three pictures become the same. From the viewpoints of the structure and the compactness of the entire device, the distances between the fluorescent screens of the side cathode-ray tubes 1 and 3, and the centers of the corresponding mirrors 11 and 14 are adjusted within the range of R-1/2R when the curvature radiuses of the mirrors 11 and 14 are supposed to be R. In addition, the mirrors 11 and 14 can be provided as fluorescent screens 30 and 32 in cathode-ray tubes. |
