Search results for "Scanning confocal electron microscopy"
showing 10 items of 21 documents
Near-field probing of active photonic-crystal structures
2002
We report a study of the optical near field of an active integrated component operating near the 1.55-mum telecommunications wavelength. The device is based on a two-dimensional photonic crystal etched in a suspended InP membrane. Topographic as well as optical information is collected by use of a scanning near-field optical microscope in collection mode, providing information about the local distribution of the losses.
Imaging of photonic nanopatterns by scanning near-field optical microscopy
2002
We define photonic nanopatterns of a sample as images recorded by scanning near-field optical microscopy with a locally excited electric dipole as a probe. This photonic nanopattern can be calculated by use of the Green’s dyadic technique. Here, we show that scanning near-field optical microscopy images of well-defined gold triangles taken with the tetrahedral tip as a probe show a close similarity to the photonic nanopattern of this nanostructure with an electric dipole at a distance of 15 nm to the sample and tilted 45° with respect to the scanning plane.
Shaded-mask filtering: novel strategy for improvement of resolution in radial-polarization scanning microscopy
2006
Radially polarized illumination produces, in combination with annular pupil filtering, the sharpest focal spot. However, the enhanced sidelobes produce an effective deterioration of spatial resolution. This study shows that if one substitutes the annular filter by one, adequately designed, shaded-mask filter, the sidelobes' strength is strongly reduced, and an important, effective improvement of resolution is achieved.
Scanning microscopy with spatial sampling of the detector plane
2013
We present the implementation of a confocal scanning microscope in which the signal detection is performed through a matrix sensor, specifically, a CCD camera. This kind of detection has several advantages over the conventional detection in confocal microscopes. One of those advantages is the possibility to recover information of the sample that vanishes when the confocal image is directly acquired by the integration of light into a signal. We demonstrate the applicability of the system which allows implementing super-resolution techniques in a very easy manner.
Super-Resolution Scanning Near-Field Optical Microscopy
2007
Scanning near-field optical microscopy (SNOM) is a method to obtain information about the optical properties of a sample at a lateral resolution below the diffraction limit of far-field microscopy. In SNOM, a light source of a dimension which is small compared to the wavelength of light and which is held at a small distance from the sample is scanned across the surface of the sample. The modulation by the sample of the light emitted from the source is recorded as a signal. As a general rule one may say that the size of the source and the distance to the sample limit the resolution of SNOM. A radiating self-emitting point dipole may be regarded as an idealized SNOM source. With such a source…
Characterisation of beam focus quality in biomedical nuclear microscopy: A Fourier optics approach
2009
Abstract The central peak widths of the 2D-autocorrelation function have been investigated as a Figure of Merit (FoM) of focus quality in nuclear microscopy using a quadrupole triplet lens system. The beam focus could be reliably characterised for direct scanning transmission ion microscopy (direct-STIM) images obtained with fluences as small as 5.8 × 10 9 ions cm - 2 which colocalisation tests showed did not introduce significant beam-induced changes in the cells.
THREE-DIMENSIONAL INTEGRAL MICROSCOPY WITH ENHANCED RESOLUTION AND DEPTH OF FIELD
2016
In this contribution we explain two new techniques developed by our group, which permit to increase the two-dimensional spatial resolution of the computed depth images in integral microscopy.
Image enhancement in photoemission electron microscopy by means of imaging time-of-flight analysis
2004
Abstract Photoemission electron microscopy (PEEM) is widely used in combination with synchrotron sources as a powerful tool to observe chemical and magnetic properties of metal and semiconductor surfaces. Presently, the resolution limit of these instruments using soft-X-ray excitation is limited to about 50 nm, because of the chromatic aberation of the electron optics used. Various sophisticated approaches have thus been reported for enhancing the spatial resolution in photoemission electron microscopy. This work demonstrates the use of a simple imaging energy filter based on electron time-of-flight (ToF) selection. The spatial resolution could be improved dramatically, even though the inst…
<title>Scanning probe microscopy of nanocrystalline iridium oxide thin films</title>
2003
Structural investigations of nanocrystalline iridium oxide thin films, prepared by dc magnetron sputtering technique were performed by scanning probe microscopy (SPM). SPM studies, using both atomic force microscopy (AFM) and scanning tunnelling microscopy (STM), indicate that the thin films are composed of grains with a size of about 20-50 nm. Fine crystallinity and small RMS microroughness of the films, being well below 2 nm, make iridium oxide thin films promising candidates for nanolithographic applications. The possibility to perform nanolithograhpic processes at a scale of less than 150 nm was successfully examined in AFM and STM modes.© (2003) COPYRIGHT SPIE--The International Societ…
Photon Scanning Tunneling Microscopy and Reflection Scanning Microscopy
1991
The Photon Scanning Tunneling Microscope (PSTM) is the photon analogue to the Electron Scanning Tunneling Microscope (ESTM). It uses the evanescent field due to the total internal reflection (TIR) of a light beam in a prism modulated by a sample attached to the prism. The exponential decay of the evanescent field is characterized by the penetration depth dp and depends on the angle of incidence θ, the wavelength and polarization of the incident beam. Changes in intensity are monitored by a probe tip scanned over the surface, and the data are processed to generate an image of the sample. Images produced by a prototype instrument are shown to have a vertical resolution of about 3 A and a late…