At present we are in the transition era from Standard-Definition Television towards High- Definition Television (HDTV). HDTV offers high-resolution images, sound of compact-disc quality and a wide-screen image format. In Europe, two interim transmission systems (D2- MAC, PALplus) are in use/under development for Extended-Definition Television (EDTV), already offering a wide-screen 16:9 image format with improved image quality. We present the first EDTV image sensor which can switch electronically between a 4:3 and a 16:9 aspect ratio. The introduction of an aspect ratio of 16:9 requires specific pixel dimensions in CCD image sensors. Optimal dimensions mean a trade off between light sensitivity and resolution. This trade off is discussed in detail for the EDTV imager. We have been able to achieve EDTV performance on a 1/2' lens compatible image sensor.