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The retina is a thin layer of neural tissue that lines the back wall inside the eye. Some of these cells act to receive light, while others interpret the information and send messages to the brain through the optic nerve. This is part of the process that enables us to see. In damaged or dysfunctional retina, the photoreceptors stop working, causing blindness. By some estimates, there are more than 10 million people worldwide affected by retinal diseases that lead to loss of vision.

The absence of effective therapeutic remedies for retinitis pigmentosa (RP) and age-related macular degeneration (AMD) has motivated the development of experimental strategies to restore some degree of visual function to affected patients. Because the remaining retinal layers are anatomically spared, several approaches have been designed to artificially activate this residual retina and thereby the visual system.

At present, two general strategies have been pursued. The “Epiretinal” approach involves a semiconductor-based device placed above the retina, close to or in contact with the nerve fiber layer retinal ganglion cells. The information in this approach must be captured by a camera system before transmitting data and energy to the implant. The “Sub retinal” approach involves the electrical stimulation of the inner retina from the sub retinal space by implantation of a semiconductor-based micro photodiode array (MPA) into this location. The concept of the sub retinal approach is that electrical charge generated by the MPA in response to a light stimulus may be used to artificially alter the membrane potential of neurons in the remaining retinal layers in a manner to produce formed images.

Some researchers have developed an implant system where a video camera captures images, a chip processes the images, and an electrode array transmits the images to the brain. It’s called Cortical Implants.

Transparent electronics is an emerging science and technology field focused on producing ‘invisible’ electronic circuitry and opto-electronic devices. Applications include consumer electronics, new energy sources, and transportation; for example, automobile windshields could transmit visual information to the driver. Glass in almost any setting could also double as an electronic device, possibly improving security systems or offering transparent displays. In a similar vein, windows could be used to produce electrical power. Other civilian and military applications in this research field include realtime wearable displays. As for conventional Si/III–V-based electronics, the basic device structure is based on semiconductor junctions and transistors. However, the device building block materials, the semiconductor, the electric contacts, and the dielectric/passivation layers, must now be transparent in the visible –a true challenge! Therefore, the first scientific goal of this technology must be to discover, understand, and implement transparent high-performance electronic materials. The second goal is their implementation and evaluation in transistor and circuit structures. The third goal relates to achieving application-specific properties since transistor performance and materials property requirements vary, depending on the final product device specifications. Consequently, to enable this revolutionary technology requires bringing together expertise from various pure and applied sciences, including materials science, chemistry, physics, electrical/electronic/circuit engineering, and display science.

A conducting plastic has been used to create a new memory technology which has the potential to store a mega bit of data in a millimeter- square device-10 times denser than current magnetic memories. This device is cheap and fast, but cannot be rewritten, so would only be suitable for permanent storage.

The device sandwiches a blob of a conducting polymer called PEDOT and a silicon diode between perpendicular wires.

The key to the new technology was discovered by passing high current through PEDOT (Polyethylenedioxythiophene) which turns it into an insulator, rather like blowing a fuse .The polymer has two possible states- conductor and insulator, that form the one and zero, necessary to store digital data.

However tuning the polymer into an insulator involves a permanent chemical change, meaning the memory can only be written once.

Three-dimensional TV is expected to be the next revolution in the TV history. They implemented a 3D TV prototype system with real-time acquisition transmission, & 3D display of dynamic scenes. They developed a distributed scalable architecture to manage the high computation & bandwidth demands. 3D display shows high-resolution stereoscopic color images for multiple viewpoints without special glasses. This is first real time end-to-end 3D TV system with enough views & resolution to provide a truly immersive 3D experience.Japan plans to make this futuristic television a commercial reality by 2020 as part of abroad national project that will bring together researchers from the government, technology companies and academia. The targeted “virtual reality” television would allow people to view high definition images in 3D from any angle, in addition to being able to touch and smell the objects being projected upwards from a screen to the floor.

Today’s microprocessors sport a general-purpose design which has its own advantages and disadvantages.

• Adv: One chip can run a range of programs. That’s why you don’t need separate computers for different jobs, such as crunching spreadsheets or editing digital photos
• Disadv: For any one application, much of the chip’s circuitry isn’t needed, and the presence of those “wasted” circuits slows things down.

Suppose, instead, that the chip’s circuits could be tailored specifically for the problem at hand–say, computer-aided design–and then rewired, on the fly, when you loaded a tax-preparation program. One set of chips, little bigger than a credit card, could do almost anything, even changing into a wireless phone. The market for such versatile marvels would be huge, and would translate into lower costs for users.

So computer scientists are hatching a novel concept that could increase number-crunching power–and trim costs as well. Call it the chameleon chip.

Chameleon chips would be an extension of what can already be done with field-programmable gate arrays (FPGAS).

An FPGA is covered with a grid of wires. At each crossover, there’s a switch that can be semipermanently opened or closed by sending it a special signal. Usually the chip must first be inserted in a little box that sends the programming signals. But now, labs in Europe, Japan, and the U.S. are developing techniques to rewire FPGA-like chips anytime–and even software that can map out circuitry that’s optimized for specific problems.

The chips still won’t change colors. But they may well color the way we use computers in years to come. it is a fusion between custom integrated circuits and programmable logic.in the case when we are doing highly performance oriented tasks custom chips that do one or two things spectacularly rather than lot of things averagely is used. Now using field programmed chips we have chips that can be rewired in an instant. Thus the benefits of customization can be brought to the mass market.

A reconfigurable processor is a microprocessor with erasable hardware that can rewire itself dynamically. This allows the chip to adapt effectively to the programming tasks demanded by the particular software they are interfacing with at any given time. Ideally, the reconfigurable processor can transform itself from a video chip to a central processing unit (cpu) to a graphics chip, for example, all optimized to allow applications to run at the highest possible speed. The new chips can be called a “chip on demand.” In practical terms, this ability can translate to immense flexibility in terms of device functions. For example, a single device could serve as both a camera and a tape recorder (among numerous other possibilities): you would simply download the desired software and the processor would reconfigure itself to optimize performance for that function.

Reconfigurable processors, competing in the market with traditional hard-wired chips and several types of programmable microprocessors. Programmable chips have been in existence for over ten years. Digital signal processors (DSPs), for example, are high-performance programmable chips used in cell phones, automobiles, and various types of music players.

Another version, programmable logic chips are equipped with arrays of memory cells that can be programmed to perform hardware functions using software tools. These are more flexible than the specialized DSP chips but also slower and more expensive. Hard-wired chips are the oldest, cheapest, and fastest – but also the least flexible – of all the options.

iDEN is a mobile telecommunications technology, developed by Motorola, which provides its users the benefits of a trunked radio and a cellular telephone. iDEN places more users in a given spectral space, compared to analog cellular and two-way radio systems, by using speech compression and time division multiple access TDMA. Notably, iDEN is designed, and licensed, to operate on individual frequencies that may not be contiguous. iDEN operates on 25kHz channels, but only occupies 20 kHz in order to provide interference protection via guard bands. By comparison, TDMA Cellular (IS-54 and IS-136) is licensed in blocks of 30 kHz channels, but each emission occupies 40 kHz,and is capable of serving the same number of subscribers per channel as iDEN. iDEN supports either three or six interconnect users (phone users) per channel, and either six or twelve dispatch users (push-to-talk users) per channel. Since there is no Analogue component of iDEN, mechanical duplexing in the handset is unnecessary, so Time Domain Duplexing is used instead, the same way that other digital-only technologies duplex their handsets. Also, like other digital-only technologies, hybrid or cavity duplexing is used at the Base Station (Cellsite).

Generally when most people think about electronics, they may initially think of products such as cell phones, radios, laptop computers, etc. others, having some engineering background, may think of resistors, capacitors, etc. which are the basic components necessary for electronics to function. Such basic components are fairly limited in number and each having their own characteristic function.

Memristor theory was formulated and named by Leon Chua in a 1971 paper. Chua strongly believed that a fourth device existed to provide conceptual symmetry with the resistor, inductor, and capacitor. This symmetry follows from the description of basic passive circuit elements as defined by a relation between two of the four fundamental circuit variables. A device linking charge and flux (themselves defined as time integrals of current and voltage), which would be the memristor, was still hypothetical at the time. However, it would not be until thirty-seven years later, on April 30, 2008, that a team at HP Labs led by the scientist R. Stanley Williams would announce the discovery of a switching memristor. Based on a thin film of titanium dioxide, it has been presented as an approximately ideal device.
The reason that the memristor is radically different from the other fundamental circuit elements is that, unlike them, it carries a memory of its past. When you turn off the voltage to the circuit, the memristor still remembers how much was applied before and for how long. That’s an effect that can’t be duplicated by any circuit combination of resistors, capacitors, and inductors, which is why the memristor qualifies as a fundamental circuit element.
The arrangement of these few fundamental circuit components form the basis of almost all of the electronic devices we use in our everyday life. Thus the discovery of a brand new fundamental circuit element is something not to be taken lightly and has the potential to open the door to a brand new type of electronics. HP already has plans to implement memristors in a new type of non-volatile memory which could eventually replace flash and other memory systems.