A decomposition optical-mechanical model of a led emitting element

Light-emitting diodes are ahead of traditional light sources in terms of luminous efficacy (luminous flux per unit of electrical power consumption), which arouses an increased interest in the developers of LED lamps in the standard size of incandescent lamps. When designing LED lamps for direct replacement of incandescent lamps, it is necessary to ensure a spherical light distribution in these lighting devices. The design of the lamp with filamentary LED emitting elements is recognized as the best in terms of uniformity of the spatial distribution of light. In this work, a decomposition model of an LED emitting element has been developed, which is created on the basis of the parameters of an optical-mechanical model of LED emitting crystals, and includes the following sequentially performed actions: – construction of a geometric model of the LED emitting element; – determination of the properties of the surface source of the LED emitting element and the angular distribution of radiation of the LED emitting element model as a point emitter; – development of a primary model of an LED crystal with subsequent adjustment of its parameters; – verification of the decomposition model by comparison with the experimentally measured parameters of the LED emitting element. An assessment of the quality of the LED emitting element model as a point emitter was carried out; for this, the averaged measured and modeled LIDCs were superimposed at the same azimuthal angles on top of each other. The discrepancies between the calculated and experimental data do not exceed 10%, which confirms a high accuracy of the LED emitting element model as a point emitter. The resulting file is the properties of the surface source and the value of the luminous flux of the LED emitting element, equal to FW = 254 mW. The model is characterized by increased versatility and can be used for LED emitting elements with an arbitrary configuration of LED crystals and LED lamps based on them.

Super-resolving light fields in microscopy: depth from disparity

Single molecule localisation microscopy (SMLM) has opened a new window for imaging fluorescently labelled biological specimens. Common 3D SMLM techniques enable data collection across an axial range of 1 - 5μm with high precision. Despite the success of 3D single molecule imaging there is a real need to image larger volumes. Here we demonstrate, through simulation and experiment, the potential of Single Molecule Light Field Microscopy (SMLFM) for extended depth-of-field super-resolution imaging, extracting 3D point source position by measuring the disparity between localizations of a point emitter in multiple perspective views.

Полевая десорбция цезия с рения

Desorption of cesium atoms from a rhenium point emitter in an electric field has been studied by method of field-desorption microscopy (FDM). Dependence of the desorbing field on degree of emitter surface coverage with Cs atoms is established. The heat of Cs-atom adsorption, which is dependent on the surface concentration of adsorbate and work function of the surface, is estimated in the framework of the model of mirror-image forces for field-induced desorption. Saturation of the rhenium emitter with carbon leads to changes in the character of desorption and in the distribution of desorption zones on the emitter surface.

The study of a new family of phase masks for three-dimensional fluorescence nanoscopy

The question of the axial coordinate determination accuracy is quite sophisticated in far field 3D fluorescence nanoscopy. The accuracy of a point emitter axial coordinate reconstruction depends among other things on the conversion efficiency of the phase mask and the microscope objective instrumental function. It was found that the instrumental functions of different microscope objectives differ significantly from each other, most have a strongly non-uniform spatial distribution of the radiation intensity in a parallel beam created by an objective focused on a point emitter. It was shown that taking into account the actual microscope objective instrumental function when calculating the phase masks allows to increase significantly the axial coordinate reconstruction accuracy.

The Effect of Point Emitter Geometric Parameters on Dustfall

In this paper, the modeling results are presented of point emitter geometric parameters determining the dispersion of dust pollution in the atmospheric air and finally also dustfall. The parameters include: the height and diameter of the emitter. Using the maps generated by “Ek100w” programme of Atmoterm company from Opole, Poland, an analysis of the PM10 dustfall value distribution on the analyzed area has been made. Fraction of dust - PM10 - was emitted from emitters of various working parameters. Three situations were analyzed: emission from a one-family (detached) building, from and industrial plant and from a power plant. Different heights and diameters for the above cases were analyzed. What results from the work, is that the mentioned parameters have a significant influence on the value of dustfall on the area surface at different distances from the emitter. With the increase of the height and diameter of the emitter, the values of dustfall decrease. The distance of the maximal values occurrence also increases. Results of similar analysis and available tools allow to design emission in practice, and thus allow a maximal limitation of ambient concentration of pollution and dustfall in areas especially exposed to industrial and superficial emission.