Abstract: A display device according to the present invention includes a display which is provided on a front surface of the display device and is a display surface on which images are displayed, an illuminance sensor which is provided on a rear surface of the display device and is a first measuring unit measuring illuminance on the rear surface, and a control unit which is a first control unit controlling brightness of the images displayed on the display.

Abstract: An image processing apparatus is obtained which is capable of performing gray-level correction while maintaining real-time property and accurately recognizing the feature of content obtained from an image signal. A luminance information detecting block detects a luminance information value about individual pixels from a luminance signal contained in an image signal. On the basis of the luminance information value, a content feature detecting block determines the feature of one frame of the video content, and obtains a content feature judge information value. On the basis of the content feature judge information value, a multiple content feature detecting block detects the feature of multiple frames of the video content, and outputs a multiple content feature judge information value to an image quality adjustment control block in an image quality adjusting block.

Abstract: A display device is provided that controls, considering affection due to a watcher's age and his viewing distance as human-visual characteristics, a display-screen brightness level at which the watcher does not feel glare. The display-screen brightness is most suitably set by simple calculation using relationships among watcher's ages, display sizes, glare levels, and screen-illuminance levels, etc. obtained by a subjective-assessment experiment. According to this display device, considering watcher's various conditions such as the age, the visual acuity, and the viewing distance, even if the watcher watches the display for a relatively long time, the watcher does not feel tiredness; thus, comfortable watching can be achieved.

Abstract: In a CRT display device including a CRT (MM tube) having brightness higher than that in the background-art CRT, it is an object of the present invention to improve contrast and prevent conspicuous recognition of noises. A video signal modulation circuit (10) modulates a video signal (9) (first video signal) into a second video signal having a signal level in an area of low gradation level lower than a signal level of the first video signal. A cathode bias voltage source (7) generates a driving voltage on the basis of the second video signal. It is therefore possible to keep the driving voltage in the area of low gradation level low and reduce brightness in the area of low gradation level of a CRT (1). As a result, noises of an image in the area of low gradation level are not conspicuously recognized and a contrast value is increased, resulting in improvement in image quality.

Abstract: In a CRT display device including a CRT (MM tube) having brightness higher than that in the background-art CRT, it is an object of the present invention to improve contrast and prevent conspicuous recognition of noises. A video signal modulation circuit (10) modulates a video signal (9) (first video signal) into a second video signal having a signal level in an area of low gradation level lower than a signal level of the first video signal. A cathode bias voltage source (7) generates a driving voltage on the basis of the second video signal. It is therefore possible to keep the driving voltage in the area of low gradation level low and reduce brightness in the area of low gradation level of a CRT (1). As a result, noises of an image in the area of low gradation level are not conspicuously recognized and a contrast value is increased, resulting in improvement in image quality.

Abstract: A display apparatus including a CRT provided with an electron gun having a focusing electrode which is applied with a dynamic focusing voltage for focusing electrons drawn from a cathode of the CRT is disclosed. The display apparatus includes a dynamic focusing circuit for producing the dynamic focusing voltage by superimposing, on a dc voltage supplied from outside, an ac voltage which has a waveform varying in synchronization with horizontal and vertical deflections of an electron beam flowing to a fluorescent screen on the anode. The display apparatus further includes a compensator for lowering the dc voltage supplied to the dynamic focusing circuit by a predetermined value while a brightness signal indicative of brightness of a screen of the CRT exceeds a threshold value.

Abstract: A display apparatus including a CRT provided with an electron gun having a focusing electrode which is applied with a dynamic focusing voltage for focusing electrons drawn from a cathode of the CRT is disclosed. The display apparatus includes a dynamic focusing circuit for producing the dynamic focusing voltage by superimposing, on a dc voltage supplied from outside, an ac voltage which has a waveform varying in synchronization with horizontal and vertical deflections of an electron beam flowing to a fluorescent screen on the anode. The display apparatus further includes a compensator for lowering the dc voltage supplied to the dynamic focusing circuit by a predetermined value while a brightness signal indicative of brightness of a screen of the CRT exceeds a threshold value.