Abstract: An apparatus for measuring a sighting direction of human eyes includes: a camera oriented toward an eye and picking up images thereof with invisible light, a first light source coaxially installed with the camera and emitting the invisible light toward the human eye, a second light source installed apart from said first light source and emitting invisible light toward the human eye, a calculator for calculating an expression of a line via the center of the pupil, an expression of a line via the position of the reflection of the first light source, and an expression of a line via the position of the reflection of the second light source, according to the images of the eye, calculating the position of the center of the corneal sphere according to the expressions of the lines via the positions of the reflections of the first and second light sources, and calculating the sighting direction of the eye according to an expression of a line via the center of the pupil obtained and the center of the corneal sphere of

Abstract: A vehicular display system can project optical images onto different areas on a front windshield in accordance with the effective height of a driver's eyes. The display system includes an image source and a mirror, either of which can be tilted manually and/or automatically. The mirror reflecting an image from the image source onto the inside of the windshield at an angle suitable for reflection toward the driver's eyes and at a height on the windshield fully within the driver's field of view. An electrically controlled seat can provide seat position and inclination signals for use in automatically adjusting the display height. In addition, a memory may hold manually entered display-height information to expedite readjustment of the display height in cases where more than one driver uses the vehicle.

Abstract: A head-up display apparatus used as an instrument display of an automobile comprises a hologram combiner provided on the front windshield on which an image is displayed overlapping the field of view. The apparatus includes a display luminosity control system which varies the brightness of the display image gradually or delays an increase and decrease in the brightness in accordance with variations in the ambient light level so as to allow a driver's eyes to adapt to the variations.

Abstract: A CRT display system for a vehicle is provided, the system comprises a CRT for displaying images, vehicle information, or so forth, a liquid crystal panel assembly disposed in front of the CRT, a vehicle information sensor, and control means for the liquid crystal panel. The vehicle information sensor is adapted for determining whether the vehicle is running or not and whether an ambient light level is high or low to provide signals indicative thereof. The control means is operable to control the transmission factor of the liquid crystal panel so as to limit a visual angle for the driver in response to the signals output from the vehicle information sensor. When the ambient light level is low and the vehicle is running, the control means controls the liquid crystal panel assembly so as to reduce the transmission factor thereof to a first level with the result that no images from the CRT are projected to the driver through the panel assembly although passengers may clearly see the images.

Abstract: An apparatus for displaying an image on a screen of a CRT (Cathode Ray Tube) applicable to a vehicle is disclosed in which the visual angle controlling filter (liquid crystal panel) is disposed in a front space of the screen of the CRT. When the vehicle runs, a predetermined voltage is applied to the visual angle controlling filter so that the light from the screen to a driver's seat is interrupted. At this time, the application of the voltage to the visual angle controlling filter is detected and a color hue of the image appearing on the screen is controlled so that all viewers except the vehicle driver can view the image on the screen through the visual angle controlling filter with the same color hue as that viewed when the vehicle stops and no application of the voltage to the visual angle controlling filter.

Abstract: Herein disclosed is a display device for use in an instrument panel of a motor vehicle. The display device comprises a display source for producing light by which visual informations are formed; a plane mirror arranged to reflect the light toward a given position; and a liquid crystal panel arranged in the given position to selectively pass the reflected light therethrough.

Abstract: A head-up display system employs a transparent hologram built into the vehicular windshield. A scanning beam is used to scan the hologram, and its luminosity is turned on and off to illuminate points making up images. Such head-up display system is compact enough to enable practical installation on a vehicle.

Abstract: A setup of meter indication display on an instrument board in an automobile, utilizing a panel type display unit such as a liquid crystal panel or an electroluminescence panel. To minimize unfavorable influence of brightness outside the car and to avoid interfering reflection of light rays incident upon the display panel, the front surface of the instrument board is recessed to provide a room, in which the display panel is disposed. The recessed areas of the instrument board surface are dark colored, and the display panel is supported by the use of, for example, a ball joint which allows the display panel to be swivelled and tilted.

Abstract: A fault indication signal from a plurality of sensors is used to advance a rotary switch to hunt in search of the terminal at which the signal appears. The terminals of the switch are associated with the corresponding visual fault indications recorded on an endless film mounted on a transport mechanism that is driven in unison with the rotary switch. Upon the occurrence of a second fault, the switch is again triggered to advance in search of the terminal where the second signal appears for successive indication of the second fault location. The switch is automatically stepped to a terminal where a signal indicating the presence of more than one fault appears for permanent indication of the number of such faults. The system can be restarted manually to provide successive indications of the first and second faults to facilitate troubleshooting.