摘要 |
<p>A particle detecting device comprising: a light source (100) for forming a diverging light beam (105), a transparent substrate (110) having first surface (112) and second surface (128). A first diffractive optical element (120) and second diffractive optical element (135) are formed on the first surface (112) of the transparent substrate (110), diverging light beam (105) passes through the first diffractive optical element (120) and reflected by the particles formed the second surface (128) of the substrate (110) to the second diffractive optical element (135) and received by a detector (145). A controller receives the signals from the detector (145) and calculates the particle size.</p> |