| 摘要 |
PURPOSE:To obtain a lens for projection free of size distortion of images in red, green, and blue by allowing the optical axis of a negative element closest to a projection cathode-ray tube to deviate from the optical axes of other element group. CONSTITUTION:On the optical axis O-O' of the lens 2'' for projection, the projection cathode-ray tube 1, an element group 7 constituting the lens 2'' for projection, and an element having negative optical power are arranged. In this case, the element 6 has its optical axis O1-O'1 deviating from said optical axis O-O' by (h). Consequently, even when each color image projection lens slants to a transmissive type screen, each color image is free of size distortion and projected to the same size. |
