Techniques are disclosed for particulate matter (PM) measurement in a medium (such as air) using flat-top intensity laser sheet beam generation. The techniques for generating the laser sheet beam may include nonspecialized optical elements (e.g., aspherical, spherical, biconvex, and/or cylindrical lenses) that are cost-effective, reduce the overall footprint of the system, and also provide for relatively increased power efficiencies compared to conventional techniques. The PM measurement system may use the laser sheet beam generated in combination with a medium flow channel to pass the medium through the laser sheet beam, thereby causing particulates within the medium to scatter light, which can be detected using a light sensor (e.g., a photodetector). The scattered light signals can then be analyzed to match them with corresponding particulate sizes and the amount of signals per particulate size can also be determined to measure the size and count of particulates within the medium.