A novel polarization converter using reflective metallic gratings and a polarization beam splitter is introduced for LCD backlight illumination. These two optical elements form a polarization rotation resonator. Broadband and high optical efficiency of polarization conversion in the visible region is achieved through the resonance of the refracted light and the surface plasmon wave in metallic ...

In modern society due to high traffic accidents, high time rates the feeling of insecurity and threat is increasing. Records in the database show that the number of new cars being bought and so is the cars being stolen locally and internationally has increased rapidly. This model focuses on two key points. First is car safety. The methods considered in this model are different from the conventi...

Portable computers and digital assistants usually require more than one power supply. These devices may need an AC/DC adapter or battery charger, a high-voltage DC/AC converter for the backlight, and other supplies for lasers, cellular radio transmitters, and auxiliaries. Swapping components in a basic switching-regulator layout alters the circuit topology to create regulators that step up, ste...

An array of spatially distributed light-emitting diodes (LEDs) can produce an illumination pattern that approaches an image by individually modulating each LED. In this letter, I analyze the first-order design of such systems in order to achieve the best match between the illumination distribution and a desired image. In particular, simple formulas are given for the optimal number of LEDs, work...