Figure 2
From: Label-free detection of nanoparticles using depth scanning correlation interferometric microscopy
Experimental defocusing response. Polystrene nanoparticles with 100 nm in diameter are immobilized on top of sensor surface. By changing the axial position of the sample stage, images are captured, and the particle contrast value, which is the normalized intensity of a camera pixel as a function of axial position, is calculated. Figure illustrates the particle contrast for one pixel corresponding to the center of one of the particles in the above images.
