Abstract: A display device includes a housing, a variable reflectance element, a display to display at least a portion of a rearward image, a display device control circuit, and an actuator to switch the variable reflectance element between first and second postures. In the first posture, the display displays the portion of the rearward image. In the second posture, the display displays the rearward image. In the second posture, the reflectivity of the incident light varies between first and second values of a first and a second illuminance, respectively. The first illuminance indicates brightness around a vehicle and is detected by a sensor. The second illuminance indicates intensity of light emitted on a front surface of the display device and is detected by another sensor. When the display displays at least the portion of the rearward image, the display is visible to a driver through the variable reflectance element.

Abstract: A 3D volume measuring apparatus using an optical measuring technique performs an accurate measurement by using a common master clock signal to move a slit beam and to perform a measuring operation using the slit beam. An optical sensor has a slit beam source which projects the slit beam onto a surface of an object. A video camera receives an image of the optical cutting line. A master clock pulse generating unit is provided for generating master clock pulses. The slit beam is scanned on the object in synchronization with the master clock pulses. Information of the image of the optical cutting line is obtained in synchronization with the master clock pulses, so that the contour of the vertical section corresponding to the optical cutting line is obtained. A chamber volume correcting method using the 3D volume measuring apparatus is provided in which method an exact cutting depth for a cylinder head can be calculated so that a chamber of the cylinder head has an exact target volume.

Abstract: XYZ coordinates of an object are measured by projecting pulse slit light onto the object, imaging the slit line formed on the surface of the object by a TV camera, and processing the video signal from the camera according to the scanning signals from the camera. The position of the slit line on the camera is detected, based on the weighted average of the intensity values of the video signal. The relation of the position of the slit line to the actual XYZ coordinates on the object has been previously established, taking account of the distortion of the lens of the TV camera and stored in a look-up table. Data read from this table is stored in a memory in synchronism with the projection of each pulse slit light. The XYZ coordinates on the object can be accurately detected even though its physical position varies at a high speed or its reflectivity changes widely.

Abstract: A system for measuring three-dimensional shapes and dimensions includes: an imaging unit which faces an object with shape changes on the surface and images by means of a TV camera the slit line formed on the object surface by projecting slit light from a slit light source at a fixed angle; and a surface feature extraction member for extracting features representing the shape changes of the object surface, based on the changes of the XYZ coordinate values of the object surface detected by triangulation based on the centroid position of the intensity distribution of the slit line image corresponding to the scanning lines from the TV camera. Based on features thus extracted, the surface shape of the object can be measured rapidly with high precision.

Abstract: An XYZ coordinates measuring system has a slit light source for projecting a slit light beam onto the surface of a work to be measured with a predetermined angle. Furthermore a television camera takes a light line formed on the surface of the work by the slit light beam to generate an output video signal. A coordinate measuring circuit has a look-up table for previously storing the interrelationship between the horizontal and vertical imaging positions of the light line and the XYZ coordinates on the surface of the actual work. The coordinate measuring circuit is adapted to process the video signal to detect the horizontal and vertical imaging positions Ks and Ls of the light line and to output the XYZ coordinates on the surface of the work from the look-up table, depending on the detected horizontal and vertical imaging positions Ks and Ls, the XYZ coordinates on the surface of the work can thus be real-time measured along the light line.

Abstract: An improvement of a vehicle collision anticipating method and device using transmitted and reflected frequency-modulated continuous waves is provided. A low frequency wave is produced by mixing a part of transmitted wave and a reflected wave from the object. The low frequency wave and a Doppler signal obtained from the low frequency wave are signal processed so as to generate signals. A predetermined distance range is obtained by multiplying a time which is determined by the distance between the vehicle and object and the velocity of said object with respect to the vehicle obtained from the Doppler signal, by a relative velocity of the object with respect to the vehicle. A collision of the object against the vehicle is anticipated by detecting the object entering the predetermined distance range in front of the vehicle.

Abstract: In a vehicle an alarm issues a warning signal just before actuation of an automatic emergency brake which operates in response to the relative speed and relative distance beween the vehicle and an obstacle in the vehicle's path.