Abstract: An apparatus for and a method of preventing a car from coming into collision with an object car running ahead or behind, by monitoring car running conditions in the front and rear of the car by the provision of front and rear sensors to give an alarm to the front and rear object cars when an emergency situation has monitored, sensing a slope of a road surface on which the car runs to remove an error caused by an inclination of the car, sensing a handle rotation of the car to enable the car to follow the front object car on a curved road and to be informed of situations in the front and rear of the car on the curved road, establishing a sufficient safety distance, and sensing an emergency situation occurring in the rear of the car to inform a driver of the rear object car of the emergency situation by the provision of a display.

Abstract: An optical distance measurement apparatus comprises a system controller for controlling the entire operation of a system, a light emitting circuit for emitting a high-power pulse light beam as a distance measuring medium to an object in response to a drive signal from the system controller, a light receiving circuit for receiving a light beam reflected from the object, a trigger signal generation circuit for generating a trigger signal indicative of a start time point for measurement of a light moving time, and a time-distance conversion circuit for measuring the light moving time in response to the trigger signal from the trigger signal generation circuit and in response to an output signal from the light receiving circuit, and for converting the measured light moving time into a distance to the object.

Abstract: Optical distance measurement apparatus and method. The apparatus comprises a light emitting circuit, a light receiving circuit, a trigger signal generation circuit, a pollution sensor, a diode abnormal state sensor, a control/time-distance conversion circuit, a cleaning device and a car collision prevention device. The pollution sensor receives a part of a light beam which is emitted from the light emitting circuit and then reflected from protecting glass mounted on a front side of the apparatus, to sense a variation in a reflectivity of the protecting glass, and discriminates a polluted state of the protecting glass in accordance with the sensed result.

Abstract: Car collision prevention apparatus and method comprises a slave processor for transmitting and receiving a laser beam or an ultrasonic wave signal to extract distance information between a car and a car in front, and a master processor for comparing the extracted distance information from the slave processor with a safety distance between the car and the front car based on a car speed and performing car accelerating or decelerating and alarm functions in accordance with the compared result. The slave processor comprises a long-distance sensing laser sensor and a short-distance sensing ultrasonic wave sensor disposed in a front side of the car, the long-distance sensing laser sensor consisting of a laser trigger circuit, a laser transmitter and a laser receiver, the short-distance sensing ultrasonic wave sensor consisting of an ultrasonic wave trigger circuit, an ultrasonic wave transmitter and an ultrasonic wave receiver.

Abstract: An apparatus and a method for measuring a distance optically using a phase variation. The apparatus comprises a light emitting circuit for emitting a high-power intermittent pulse light beam to an object, a light receiving circuit for receiving a light beam reflected from the object, a signal generation/phase difference detection circuit for generating first and second pseudo intermittent pulse signals in response to a drive signal from the light emitting circuit and an output signal from the light receiving circuit, respectively, detecting a phase difference between the generated first and second pseudo intermittent pulse signals and measuring a phase-delayed time on the basis of the detected phase difference, and a controller for performing a control operation in response to an output signal from the signal generation/phase difference detection circuit.