The phantom test. Microtest tubes were filled with anti-AFP reagents with concentrations of 0.3, 0.2, 0.1, 0.01, and 0.005 emu/g that were 0.25 g in weight. The image process for the optical image, the magnetic images composed of I and only I larger than 50%, and the fused image (A). The dependence of Imax of the red spot in the magnetic image on the sample distance and the sample concentration (B). The dependence of the integral of I on the sample distance and the sample magnetism (C).