Laser spot measurement using simple devices

We have designed and tested an automated simple setup for quickly measuring the profile spot size of a Gaussian laser beam using three cost-affordable light sensors. Two profiling techniques were implemented: imaging CMOS 2D array (webcam) scanning knife-edge-like single photodiode LDR. The methods sensors compared to determine their accuracy lasers two different wavelengths technologies. verify that it is possible use low-cost webcam with 1% uncertainty on waist, 1.5% error waistline position, less than 3% in determining minimum radius. measurement most stable since not affected by change intensity. In addition, we show inexpensive LDR sensor estimate 11% error.