ahtesham_rulz

thanks for the advice. i am planning to build from purchased devices

Hello, I am a 2nd year electronics student. I am trying to do a simple project of counting the time for which a signal should be open. I have thought of placing a laser at one side of the road and a sensor at exactly the opposite, when a vechile crosses this laser it is blocked from reaching the sensor and at exactly the same time a device starts counting the duration of obstruction. Can any one please help me out as for which devices to be used. Any other sugestion concerning this idea will be greatly appreaciated. please : - I am just a new comer in the field of electronics.