Ultra-high luminance lamps emitting white light with a well-scattered blue spectrum from InGaN/GaN laser diodes and a phosphor-converted yellow spectrum show speckle contrast values as low as LED. Spectral behavior of the laser diodes is analyzed to find the reason why such low values are obtained. As a result, the PWM-driven, multilongitudinal mode with dynamically broadened line-width is foun...

We analyze a sample of bright long bursts and find that the pulses duration have a lognormal distribution while the intervals between pulses have an excess of long intervals (relative to lognormal distribution). This excess can be explained by the existence of quiescent times, long periods with no signal above the background. The lognormal distribution of the intervals (excluding the quiescent ...

The observed fraction of pulsars with interpulses, their period distribution and the observed pulse width versus pulse period correlation is shown to be inconsistent with a model in which the angle α between the magnetic axis and the rotation axis is random. This conclusion appears to be unavoidable, even when non-circular beams are considered. Allowing the magnetic axis to align from a random ...

A previous paper described LWIR Pupil Imaging with a sensitive, low-flux focal plane array, and behavior of this type of system for higher flux operations as understood at the time. We continue this investigation, and report on a more detailed characterization of the system over a broad range of pixel fluxes. This characterization is then shown to enable non-uniformity correction over the flux ...

Due to great value of the time constant of the integrator circuit, a hardware defined PWM (Pulse Width Modulation) signal makes it possible to build a Digital to Analog Converter (DAC) characterized by a relatively long response time. An attempt at creating the software defined PWM signal leads to increased response time of the DAC converter with a coefficient several hundred times longer than ...

This paper presents a technique to improve the performance of laser phase-shift range finders. The phase measurement is performed by using a new method to extract the phase-shift data from the peak of received and transmitted intermediate frequency signal amplitudes. The pulse width modulation is used to minimize the noise effect and enhance the signal amplitude measurement. The advantages of p...

By using a non linear discrete time model, this paper shows how to predict bifurcations in a two cells chopper and analyses the road to chaos. Equilibrium points and their stability are investigated in an analogical way to determine the nature of the bifurcations. The global behaviour is studied by using bifurcation diagrams showing collisions between fixed points and borderlines. The border co...

A novel overmodulation strategy for space-vector pulsewidth modulated (PWM) inverters is proposed. The method, which increases the range of linear control of the output voltage by 10%, is based on Fourier series representation of the reference voltage.

Whitepaper The technology for solar photovoltaic battery charge controllers has advanced dramatically over the past 5 years (1995-2000). The most exciting new technology, PWM (Pulse Width Modulation) charging, has become very popular. Some Frequently Asked Questions about PWM battery charging are addressed here.