An x-ray transmissive housing window for reducing non-uniform attenuation of x-rays in a rotationally driven x-ray device is disclosed. The x-ray tube is disposed within an interior portion of an outer housing that is filled with cooling fluid. An x-ray beam produced by the tube passes through the housing window, which is disposed in a port defined in the outer housing. The housing window includes a convexly shaped inner surface adjacent the cooling fluid. The shape of the window's inner surface cooperates with centripetal and other dynamic forces within the x-ray device to act on bubbles that form in the cooling fluid and attach to the window's inner surface. These forces create a moving force that acts on the bubbles at the housing window inner surface. The convex curvature of the inner surface enables the dynamic forces to displace the bubbles from the x-ray beam transmission region of the housing window.