Nano-optical microscopy: now and its industrialization

It is a review about the industrialization of Nano-Optical Microscope (NOM, also referred to as the Near-field Optical Microscope). Two comparisons of AF/PSTM (Transmission Mode) with the first generation commercial A-SNOM and AF/RNOM(Reflective Mode) with A-RNOM have discussed. The commercially used A-SNOM can only obtain a transmissivity image of A-SNOM-T(x,y), but AF/PSTM can obtain the separating the transmissivity image PSTM-T(x,y) and the refractive index imge PSTM-n1(x,y). AF/RNOM can obtain the lower contrast reflective index image but ARNOM cannot. The reason how could Pohl have obtained the first A-SNOM image with a resolution of 20-25nm in 1984 but the commercial A-SNOM-T(x,y) only with the resolution in the 50~100nm range is also discussed. Conclusion on the proposal of AF/PSTM and combined AF/RNOM may be the best candidate for the second generation commercial use of NOM.