A phase contrast image is generated on the basis of a plurality of radiation images of an object taken in imaging positions which are different from each other in the distance from the object. The directory terminal retrieves screen interface information associated with the identifier and renders a user interface on a display screen of the directory terminal based on the retrieved information. Also, in interlayer prediction, a prediction signal obtained from an intra-layer image to which the current target block belongs and a prediction signal obtained from a reference layer image may be weighted and then used as a prediction signal. A switching device is connected to the first and second power sources, and to the circuit board for selectively connecting the first power source or second power source between a power source recharger and the circuit board. During the peptization process, hydrolysis and condensation reactions occurs between different metal hydroxyl compounds. As an illuminating optical system is provided rotatably around an optical axis of a projecting optical system, the position of the illuminating optical system can be varied depending on whether the projector device is used or not used, and the overall thickness of the projector device can be thereby reduced.