How to Measure Laser Beam Quality

Measure the length and depth of the laser to determine its quality.

A laser is a device that emits electromagnetic radiation through amplifying an optical signal by stimulating the emissions of protons. Testing how fast a beam is emitted through a laser as well as how high or low the beam is can determine beam quality either for scientific use or simply for entertainment and personal use. You can measure laser beam quality with a laser beam profiler.

Things You'll Need

• Laser beam
• Mount
• Ruler
• White piece of paper

Instructions

1. Mount the laser you wish to measure solidly to any base such as a table or tripod.

2. Secure a white piece of paper to a wall with an agent that you prefer. Confirm that it is in the range of the laser and no more than 3 meters away from the laser.

3. Turn on the laser so that it displays its beam on the white piece of paper.

4. Measure the diameter of the laser beam from its exit on the laser. Measure the diameter of the beam on the white paper.

5. Compute the divergence of the laser beam by using this formula: 2arctan(Df-Di/2l). Arctan is the angle that has a tangent equal to a given number. Replace Df with the second diameter measurement. Replace Di with the first diameter measurement. Replace l with the laser's length, as displayed on the white paper, in centimeters. Then calculate the result.

References

• Thor Labs: Scanning Slit Optical Beam Profilers