Recent experimental and theoretical works on high resolution electron microscopy of crystal lattices, which are based on many beam situation, have been introduced after reviewing historical works based on two beam situation. It is shown that the position of Ca and Na atoms in labradorite feldspar can be identified by the high resolution electron microscopic images taken in three different orientations. It is also shown theoretically that in the very high resolution electron microscopic images of gold single crystals, taken by zero-aberration lens at 1 MeV the fine structure similar to the images of nucleus and electron cloud can be observed.
A. method using a high speed scanning Fabry-Perot interferometer is proposed for a high resolution spectroscopy of a very weak light. This method is distinguished from the conventional method; such as pressure scanning Fabry-Perot interferometer, in the following aspects. For detection of a very weak signal from the spectrometer, an ensemble average of the multiple samplings is used instead of a long time average. Signal light and reference light are put into the spectrometer alternately and the sampler is controlled by the output pulse due to the reference light. Thus the sampl-ing point can be fixed on a scanned wavelength of the spectrometer. The method enables us to determine a wavelenght shift of 10-3Å for weak light with the power level below 10-12 or 10-13 watts without rigorous frequency stabilization of the light source and the interferometer. Expermental results on the light scattering in stained water show that the proposed detection system is entirely satisfactry.
The main disadvantage of a conventional electroradiography is the low X-ray sensitivity of the electroradiographic plate. To overcome this disadvantage we have developed a highly sensitive electroradiographic process. The electroradiographic plate is integrally constructed of an upper transparent dielectric layer, a photoconductive multilayer, an inner transparent dielectric layer, a transparent electrode and a phosphor layer. The process forms an electrostatic latent image on the upper dielectric layer by two corona charging steps. We have succeeded in a great increase of photosensitivity of the photoreceptor. It is possible to utilize the luminescence from a phosphor layer as in the conventional X-ray film. The X-ray sensitivity of the plate with a phosphor layer approaches that of X-ray films. For medical purposes, a distinct picture of mamma, breast, thyroid gland, bone and skin can be obtained by using an ordinary X-ray tube, wherein the tube voltage is 40_??_90 kVp and dose is 40_??_70 mAs.
Isolated conical etch pits developed on the negative c-surface and isolated etch pits revea-led on the positive c-surface of a LiNbO3 crystal with 1HF: 2HNO3 solution were found to be due to dislocations as a result of using x-ray topographys.