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.