Abstract: There is provided a light source control apparatus including an image change determination unit that determines presence or absence of at least one of a change of an image signal and the image signal, and a light source controller that reduces luminous output of a light source at a predetermined decreasing rate when the image change determination unit determines at least one of no change of the image signal and absence of the image signal.

Abstract: A projection display apparatus and an actuation control method thereof are provided. A projection display apparatus includes an apparatus body that forms an optical image projected on a screen, a projection lens that projects the optical image formed by the apparatus body on the screen, a lens actuator that allows the projection lens to be shifted in a vertical direction or in a horizontal direction relative to the apparatus body, and a shift controller that limits a range of shift movement by the lens actuator such that a center position of the projection lens does not go outside of a quadrangle region of which the intersection point of diagonals is located coaxially with the position of the optical axis of the apparatus body.

Abstract: There is provided a light source control apparatus including an image change determination unit that determines presence or absence of at least one of a change of an image signal and the image signal, and a light source controller that reduces luminous output of a light source at a predetermined decreasing rate when the image change determination unit determines at least one of no change of the image signal and absence of the image signal.

Abstract: A projection display apparatus and an actuation control method thereof are provided. A projection display apparatus includes an apparatus body that forms an optical image projected on a screen, a projection lens that projects the optical image formed by the apparatus body on the screen, a lens actuator that allows the projection lens to be shifted in a vertical direction or in a horizontal direction relative to the apparatus body, and a shift controller that limits a range of shift movement by the lens actuator such that a center position of the projection lens does not go outside of a quadrangle region of which the intersection point of diagonals is located coaxially with the position of the optical axis of the apparatus body.

Abstract: A method and a device for converting data of a first format discriminated by an identifier into picture data of a second format different from the first format. In converting the data of the first format into the picture data of the second format different from the first format, discrimination picture data for discriminating the picture data is generated, while data relevant for correlating the picture data to the discriminated picture data is also generated. If, in displaying the converted picture data, the discrimination picture data is selected, the picture data correlated to the discriminated picture data is displayed based on the data relevant for correlating the picture data to the discriminated picture data.

Abstract: The present invention is relative to a method and a device for converting data of a first format discriminated by an identifier into picture data of a second format different from the first format. In converting the data of the first format into the picture data of the second format different from the first format, discrimination picture data for discriminating the picture data is generated, while data for relevance for correlating the picture data to the discriminated picture data is also generated. If, in displaying the converted picture data, the discrimination picture data is selected, the picture data correlated to the discriminated picture data is displayed based on the data for relevance correlating the picture data to the discriminated picture data.

Abstract: A synchronous control device is disclosed which is capable of obtaining stable synchronization regardless of the kind of image source even when the automatic synchronous control circuit cannot operate in the normal manner.The device includes a phase comparator, an integrator, a horizontal oscillation circuit, and a horizontal synchronous control circuit composed of a frequency measuring section consisting of a digital frequency measuring circuit, etc. and a control section consisting of a frequency determining circuit, an oscillation frequency control circuit, etc. The frequency measuring section measures the input horizontal synchronizing frequency and transfers it to the control section as digital data, and the control section determines the true value of the input synchronizing frequency by the frequency determining circuit while monitoring the transition of the frequency data per unit time.