Any ordinary electric light bulb that is fitted so that it points upwards will often produce a bright circle of light on the ceiling above. Especially if it is fitted to a light with a dense fabric shade.
To avoid this effect, replace the bulb with a crown silver bulb. This is a bulb which has a special coating across the top. The light from the bulb is reflected downwards and outwards only. Because it is softer and warmer the wattage of the crown silver bulb will have to be higher than that of an ordinary bulb if the same degree of brightness is required.