No no.. i mean if im using the laser, i will using the 300Mhz clock. if im using the infrared, the clock on FPGA is 50Mhz can be divided to Khz so that the clock from the FPGA is same with the speed of the sensor i will attach..
for this project purpose, using the laser will really burden me, and for some reason that is why i want to use either ultrasonic or infrared.. if im using laser, the costing for the project will increase and increase.. futhermore, there are still none the laser sensor that suit for simple project.. some of them use for industrial only