| 摘要 |
An image pick-up apparatus comprising an image sensor with a matrix of radiation-sensitive elements, notably a CCD image sensor, is provided with a control circuit for selecting gate electrodes as collecting gate electrodes or as isolating gate electrodes by application of an electric potential of suitable polarity. Groups of collecting gate electrodes are separated from one another by isolating gate electrodes. The surface area of such a group of collecting gate electrodes co-determines the modulation transfer function and hence the spatial resolution of the image sensor; this surface area, and hence the spatial resolution, can be adjusted by adjustment of the electric potentials. Notably the spatial resolution can be rendered dependent on the different modes of operation of the image pick-up apparatus, for example when the image pick-up apparatus forms part of an X-ray examination apparatus which is suitable for fluoroscopy as well as for making X-ray images. Furthermore, the spatial resolution can be adjusted so that it differs in different directions. In the case of an image pick-up apparatus comprising a plurality of image sensors, each of which picks up the same image, be it with a shift relative to one another, an image is composed from the images supplied by the various image sensors. Differentiation of the spatial resolutions of the images constituting the composite image enables a spatial resolution in the composite image to be achieved which is the same and higher in all directions. <IMAGE> |
