In this paper, we present a high accuracy laser range finder and velocimeter using ultra-fast time-to-digital converter (TDC). The system operation is based on the measuring the round-trip time of a narrow laser pulse. A low-dark current high-speed PIN photodiode is used to detect the triggered laser beam and to produce start signal. The pulsed laser diode generates 45W optical power at 30ns du...

background and objective: vep is a powerful method to study visual system via evaluating evoked potentials. technologic and instrumental restrictions may be the reason of having studies on optical modulation and induction such as color, spatial frequency and contrast. developments of computer software and hardware may lead to an increase in the flexibility of pattern designs. material and meth...

we study the dynamics of two three-level atoms interacting with independent bosonic lorentzian reservoirs at zero temperature. such systems can be created in far astronomical objects. quantum mechanical behaviour of these particles can produce detectable effects on the spectroscopic identifications of these objects, if such behaviour remain stable during the interaction with their media. it is ...

in this study, the possibility of estimating wheat density was investigated by using a non-destructive method of output voltage of the light received by the photovoltaic cells. for the static tests, treatments and procedures, a system was designed and built. an experiment with different density on the wheat crop was carried out. the components of optical system clouding: photocells, led lights ...

For an indoor non-directed line of sight optical wireless communication (NLOS-OWC) system we investigate the optimized Lambertian order (OLO) of light-emitting diodes (LEDs). We firstly derive an expression for the OLO from a conventional Lambertian LED model. Then, we analyze the indoor multi-cell NLOS-OWC channel characteristics including the optical power distribution and the multipath time ...

in radiation cancer treatments, the most of the side effects could be minimized using a proper dosimeter. gel dosimeter is the only three‑dimensional dosimeter and magnetic resonance imaging (mri) is the gold standard method for gel dosimeter readout. because of hard accessibility and high cost of sample reading by mri systems, some other alternative methods were developed. the optical computed...

At first step polymer optical fibers (POFs) are used in short distance for optical data transmissions. At second step SiO2 nanoparticles were prepared by sonochemical-assisted method. Silica nanoparticles were added to polymer matrix to prepare polymer based nanocomposites. Most of the POF applications are in the medical and electrical devices. There are several methods for fabrication of POFs,...

Ultra optical glasses are proposed for attaining noble glazes of high reflection and shine. In addition, these glasses can be used as semi-mirrors and optical instruments. In this reseach attempts were devoted mainly to introduce a glass system with the highest possible refractive index in which the highest reflection is desirable. Thus different amounts of heavy metal oxides modifiers, such as...