Abstract: An illumination device includes a light source, a pair of wedge prisms, and a driving portion. The pair of wedge prisms deflect incident light. The driving portion includes a gear and a gear, and causes the pair of wedge prisms to rotate about a rotation axis by using the gear and the gear. The pair of wedge prisms include a wedge prism held by a barrel and a wedge prism held by a barrel. The barrel is disposed inside the barrel. A gear whose center axis is the rotation axis is provided on an outer periphery of the barrel. A gear whose center axis is the rotation axis is provided on an inner periphery of the barrel. The gear is disposed on an outer peripheral side of the gear and meshes with the gear. The gear is disposed on an inner peripheral side of the gear and meshes with the gear.

Abstract: A light irradiation device includes a light source, an optical member and a sensor. The light source emits light. The optical member is supported so as to rotate around a rotation axis and includes a prism part that emits detection light based on the light. The sensor receives the detection light and detects a light amount of the detection light. The light amount of the detection light received by the sensor changes depending on a position of the optical member in a rotation direction when the optical member rotates.

Abstract: An illumination device includes a light source, a pair of wedge prisms, and a driving portion. The pair of wedge prisms deflect incident light. The driving portion includes a gear and a gear, and causes the pair of wedge prisms to rotate about a rotation axis by using the gear and the gear. The pair of wedge prisms include a wedge prism held by a barrel and a wedge prism held by a barrel. The barrel is disposed inside the barrel. A gear whose center axis is the rotation axis is provided on an outer periphery of the barrel. A gear whose center axis is the rotation axis is provided on an inner periphery of the barrel. The gear is disposed on an outer peripheral side of the gear and meshes with the gear. The gear is disposed on an inner peripheral side of the gear and meshes with the gear.

Abstract: A light irradiation device includes a light source, an optical member and a sensor. The light source emits light. The optical member is supported so as to rotate around a rotation axis and includes a prism part that emits detection light based on the light. The sensor receives the detection light and detects a light amount of the detection light. The light amount of the detection light received by the sensor changes depending on a position of the optical member in a rotation direction when the optical member rotates.

Abstract: A vehicular display control device includes an image acquisition section configured to acquire a first captured image obtained by capturing a back or a side of a vehicle and a second captured image including an image obtained by a driver of the vehicle by facing to a left side or a right side with respect to a vehicle's traveling direction and a display controller configured to make a head-up display mounted on the vehicle display both of a first display image based on the first captured image and a second display image based on the second captured image on different display screens respectively.

Abstract: A light emission control device includes a partial region feature quantity detector, an enlarged region feature quantity detector, a whole screen feature quantity detector, and a light emission controller. The partial region feature quantity detector detects a feature quantity of the image as a partial region feature quantity. The enlarged region feature quantity detector defines the partial region of interest and the partial regions neighboring the partial region of interest, and detects a feature quantity of the image of the enlarged region. The whole screen feature quantity detector detects this feature quantity as a whole screen feature quantity. On the basis of the partial region feature quantity and the enlarged region feature quantity pertaining to the partial region of interest, and the whole screen feature quantity, the light emission controller controls the light emission luminance of the light emission unit corresponding to the partial region of interest.

Abstract: A light emission control device includes a partial region feature quantity detector, an enlarged region feature quantity detector, a whole screen feature quantity detector, and a light emission controller. The partial region feature quantity detector detects a feature quantity of the image as a partial region feature quantity. The enlarged region feature quantity detector defines the partial region of interest and the partial regions neighboring the partial region of interest, and detects a feature quantity of the image of the enlarged region. The whole screen feature quantity detector detects this feature quantity as a whole screen feature quantity. On the basis of the partial region feature quantity and the enlarged region feature quantity pertaining to the partial region of interest, and the whole screen feature quantity, the light emission controller controls the light emission luminance of the light emission unit corresponding to the partial region of interest.

Abstract: A display device 1 has a light source 8, a scattering member for scattering light from the light source, an image plate 10 for transmitting the light scattered by the scattering plate and an optics 3 having a lens for focusing light from the image plate and transmitting the light to an eye of the viewer. According to the device, the image is focused on or around the pupil in the Maxwellian view condition, allowing even the myoptic and hyperoptic person to see the displayed image clearly.

Abstract: A CRT display apparatus capable of displaying images in high contrast and high brightness without causing noises and halftone-reproduction degradation within dark areas is disclosed. The apparatus includes a circuit for generating an R-control signal, a G-control signal and a B-control signal by removing, from each of the R-, G- and B-video signals, portions which are below a predetermined level in amplitude, an amplification circuit for inverting and amplifying the R-, G- and B-control signals, and a selection circuit for selecting, for each of the three G1 electrodes, either a corresponding one of the R-, G- and B-control signals inverted and amplified by the amplification circuit or a potential of a predetermined value in accordance with an instruction from an outside, and applying each of the three G1 electrodes with a selected one of the corresponding one of the R-, G- and B-control signals and the potential.

Abstract: When an interval between a Gm electrode and a cathode is broadened with temperature, a potential change similar to a case that a Gm electrode voltage is lowered is generated. If a cathode voltage is constant, a quantity of electrons which pass is decreased whereupon a screen of a cathode ray tube becomes dark. A Gm electrode voltage control circuit is provided to a Gm electrode voltage source for control an applied voltage to the Gm electrode by time information from a time-measuring circuit such that the change of the interval between the cathode and the Gm electrode is corrected during a period of time between the time the voltage is applied to each electrode of a Hi-Gm tube and the time the change of a size of the interval between the cathode and the Gm electrode is saturated.

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 CRT display apparatus capable of displaying images in high contrast and high brightness without causing noises and halftone-reproduction degradation within dark areas is disclosed. The apparatus includes a circuit for generating an R-control signal, a G-control signal and a B-control signal by removing, from each of the R-, G- and B-video signals, portions which are below a predetermined level in amplitude, an amplification circuit for inverting and amplifying the R-, G- and B-control signals, and a selection circuit for selecting, for each of the three G1 electrodes, either a corresponding one of the R-, G- and B-control signals inverted and amplified by the amplification circuit or a potential of a predetermined value in accordance with an instruction from an outside, and applying each of the three G1 electrodes with a selected one of the corresponding one of the R-, G- and B-control signals and the potential.

Abstract: A cutoff adjustment method of a CRT using a Hi-Gm tube is proposed as well as a problem that luminance of a display screen is changed by a fluctuation of a Gm voltage to be applied to a Gm electrode in relation to fluctuations of currents flowing into the Gm electrode and a G2 electrode is solved. On this occasion, the cutoff adjustment method of the Hi-Gm tube sets such that a Gm voltage value of a Gm electrode voltage source and a black level bias voltage value applied to a cathode for displaying a black level agree with each other. Further, the CRT display device having the Hi-Gm tube is constituted such that it is provided with a voltage detection circuit in an output side of the Gm electrode voltage source for measuring a fluctuation of an output voltage from the Gm electrode voltage source to keep the Gm voltage constant by a feedback from the voltage detection circuit.

Abstract: A CRT display apparatus including a CRT having an electron gun is disclosed. The electron gun includes a cathode, and a G1 electrode, a G2 electrode and a G3 electrode disposed in that order for drawing electrons from the cathode. The electron gun further includes a modulating electrode disposed between the G2 electrode and the G3 electrode. The CRT display apparatus is provided with a controller for controlling a value of a voltage applied to the modulating electrode in order to suppress or interrupt an electron beam flowing from the cathode to a screen of the CRT.

Abstract: A display apparatus includes a CRT, the CRT including an electron gun having a cathode, a G1 electrode, a G2 electrode, and a G3 electrode disposed in that order to draw electrons from the cathode. The electron gun further has a modulating Gm electrode disposed between the G2 and G3 electrodes. The display apparatus is provided with a controller for controlling a value of a voltage applied to the Gm electrode to adjust brightness of a picture on a screen of the CRT.

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 is disclosed. The CRT includes an electron gun having a cathode, a G1 electrode, a G2 electrode and a G3 electrode disposed in that order to draw electrons from the cathode. The electron gun further has a modulating Gm electrode disposed between the G2 and G3 electrodes. The display apparatus is provided with a controller for controlling a value of a voltage applied to the Gm electrode to adjust brightness of a picture on a screen of the CRT.

Abstract: A CRT display apparatus including a CRT having an electron gun is disclosed. The electron gun includes a cathode, a G1 electrode, a G2 electrode, and a G3 electrode disposed in that order for drawing electrons from the cathode. The electron gun further includes a modulating Gm electrode disposed between the G2 electrode and the G3 electrode. The CRT display apparatus is provided with a current measuring circuit measuring a current flowing through the Gm electrode and a controller for controlling a value of a voltage applied to the Gm electrode according to a value of the current measured by the current measuring circuit for the purpose of preventing the electron beam flowing from the electron gun to the screen of the CRT from becoming excessive.

Abstract: A cutoff adjustment method of a CRT using a Hi-Gm tube is proposed as well as a problem that luminance of a display screen is changed by a fluctuation of a Gm voltage to be applied to a Gm electrode in relation to fluctuations of currents flowing into the Gm electrode and a G2 electrode is solved. On this occasion, the cutoff adjustment method of the Hi-Gm tube sets such that a Gm voltage value of a Gm electrode voltage source and a black level bias voltage value applied to a cathode for displaying a black level agree with each other. Further, the CRT display device having the Hi-Gm tube is constituted such that it is provided with a voltage detection circuit in an output side of the Gm electrode voltage source for measuring a fluctuation of an output voltage from the Gm electrode voltage source to keep the Gm voltage constant by a feedback from the voltage detection circuit.

Abstract: A CRT display apparatus including a CRT having an electron gun is disclosed. The electron gun includes a cathode, and a G1 electrode, a G2 electrode and a G3 electrode disposed in that order for drawing electrons from the cathode. The electron gun further includes a modulating electrode disposed between the G2 electrode and the G3 electrode. The CRT display apparatus is provided with a controller for controlling a value of a voltage applied to the modulating electrode in order to suppress or interrupt an electron beam flowing from the cathode to a screen of the CRT.