RESUMO
A new type of ellipsometer using an integrated analyzer composed of 12 sub-analyzers with different azimuth angles was constructed and studied. By using a two-dimensional CCD array camera to measure the light intensity emerging in parallel from each sub-analyzer with the azimuth angles uniformly distributed in the range of about 180 degrees , the ellipsometric parameters were extracted within the data acquisition time less than 1 second. The ellipsometric parameters for the polished bulk Si sample were measured to show good agreement with the results measured by using another two ellipsometric methods. The new method having the merits of high speed and reliability in the optical data measurement can be potentially used in the fields where the in situ data acquisition with high precision is the key issue as required.
RESUMO
The interference of light has been analyzed for a film structure by considering that a spatial separation exists for the two neighboring light beams to be interfered in the space. There is a significant difference between the situations of the interference with or without consideration of the spatial effect, especially around the region where the phase delay delta=pi and 2pi by taking the example of the one-layered SiO2/Si structure. It is reasonable to extract the optical parameters by neglecting the spatial effect only for the thinner film with a thickness much smaller than a wavelength, which satisfies the condition that delta
RESUMO
We report a structure with 4 thin film layers composed of pure metal and dielectric materials and prepared by sputtering. The reflectance and transmittance are lower than 5% with the absorption to be achieved higher than 95% in the 400-1000nm wavelength region as match to the solar radiance spectrum. The thermal emittance of the structure is in the range of 0.063-0.10 through data analysis. The good reproducibility and stability of spectral data associated with the deposition process imply the advantage of the solar energy absorber which is cost-effective in application.
RESUMO
A new charge-coupled device (CCD) spectrometer has been studied and constructed by using a two-dimensional CCD detector and an integrated grating consisting of 10 subgratings. Effective spectral images of 268 mm along the dispersion direction have been densely folded 10 times to cover the full 200-1000 nm working wavelength range without any mechanical moving elements. The results show that the system has a spectral resolution and acquisition time of better than 0.07 nm and less than 100 ms, respectively, in the entire spectral range after system calibration.
