| 摘要 |
A near-field scanning optical microscope uses short-circuit current or open-circuit voltage signals from a photosensor to generate and display an image of an object. The photosensor includes two pairs of Schottky-barrier contacts positioned on the photosensor's semiconductor surface along two orthogonal axes. Together the contact pairs define a gap, within which the object to be viewed is placed. When the microscope scans a beam of light over the gap, the photosensor produces two signals, each of which indicates the position of the light beam between one of the contact pairs. The microscope includes a computer that receives the signals from the photosensor during two scans, one conducted without the object on the surface of the photosensor (the "background" scan), and the other conducted with the object in place (the "object" scan). A computer uses the signals to produce a background scan dataset and an object scan dataset, both of which are processed to remove the effects of the light beam's Gaussian profile. The computer then subtracts the object scan dataset from the background scan dataset to produce raster image data, which it uses to generate an image of the object on a display device.
|
