Keyboard

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The Bottom Line: Logitech's $200 G19 Gaming Keyboard boasts a built-in color LCD with exciting capabilities, as well as lots of little improvements over previous models. But with few apps--thus far--that take advantage of the screen in a meaningful way, the G19's potential remains largely untapped. Until the community software effort gets rolling, we can't recommend spending this much on a keyboard that, while flashy, has yet to realize its full potential.

The Bottom Line: The Logitech diNovo for Notebooks looks sexy and is comfortable for typing, but it's a pricey upgrade for a keyboard that lacks integrated USB ports and
backlit keys.

The good

Thirty programmable keys; profile switching; nice selection of vanity keys; automatically loads custom game configurations.

The bad

Not very comfortable for everyday typing; no adjustable height and angle; wrist pad isn't soft and can't detach from keyboard

laser mouse

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A laser mouse is a type of computer mousing device that uses a laser beam rather than a ball to track the movement of the user's hand. Laser mice are becoming increasingly common because they are perceived to have better tracking ability. In addition, they are not as subject to gumming up and subsequent distortion of the signal as conventional ball mice. The lack of moving parts also makes them far less subject to damage.

Preceding the laser mouse was the optical mouse which became widespread in the late 1990s, shipping as an extra feature on many computer systems. Users immediately began to sing the praises of the optical mouse, saying that it made mousing work much easier than traditional mice, and it is becoming increasingly difficult to find a ball mouse as a result. The optical mouse is also available in a wireless format, making it an extremely versatile and flexible tool for users who like to have free range of their cordless desks.

With the introduction of a graphical user interface in the late 1980s, computer companies saw the need for some sort of device that could be used to interact with the computer, which had transcended the boundaries of the traditional text-based user interface. The mouse was introduced and became a quick success — very few computer users work without mice now, although it is technically possible to utilize keyboard shortcuts to bypass the mouse. However, using a mouse is often quicker and easier. As anyone who has used traditional roller mice knows, the roller ball tends to get gummed up with material from the workspace it is employed in and can ultimately start to malfunction until taken apart and cleaned. Optical and laser mice were an excellent introduction to the computing world, because it is not as subject to interference.

An optical mouse usually uses a light emitting diode (LED), which is frequently red, although mice in other colors such as blue are not uncommon. A laser mouse, on the other hand, which is a type of optical mouse, is different because it uses a laser beam which is invisible, or nearly invisible, to the human eye. Logitech brought the first laser mouse to the market in 2004 with its Logitech MX 1000. The beam emitted by the laser mouse moves with the user's hand, triggering an optical sensor system. It works in tandem with a system which tracks how far the mouse has moved by bouncing hundreds of images every second, constantly updating the position of the mouse and the subsequent position of the cursor on the screen.

In general, the laser mouse moves very smoothly and accurately, although if the system memory is bogged down, it will cause the cursor to lag, along with everything else. In addition, the laser mouse can reflect from almost any surface, meaning that a mouse pad is not necessary. Users have been known to employ anything from desk tops to pant legs as a reflective surface for their laser mouse, making it a great go-anywhere tool.

Monochrome & Color-Field-Sequential LCoS microdisplays

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HOLOEYE Sytems is a professional integrator of microdisplay technologies for specialty applications and markets and offers complete solutions and development services. Primarily developed for HDTV rear projection TVs, LCOS (Liquid Cristal on Silicon) microdisplays offer high resolution with small pixels and high contrast. HOLOEYE Systems offers LCOS microdisplays components for the development of HUDs, Near-to-Eye applications and all other applications where high resolution with high contrast is needed. All LCOS microdisplay components are available including all hardware and engineering support. LCOS microdisplay technology can compete and in some cases even outperform all other display technologies with respect to resolution, size, ease of use, quality and price. HOLOEYE Systems's OEM LCOS microdisplay service includes basic implementation assistance and performance specification for specialized applications. HOLOEYE Systems offers modification of driver parameters for customer specific requirements resulting in low-cost intelligent driver boards ready for mass production. This positions HOLOEYE Systems to be a key-supplier accross numerous markets and to be the very first company to market a "complete solution" to the end-user, whether they are in the defense, medical or aerospace industry. Even the highly cost-sensitive automotive industry is able to develop HUD systems based on high resolution HDTV LCOS microdisplay technology.

HOLOEYE Systems provides LCOS microdisplay technology to military & civil defense, aerospace, automotive, optical 3D measurement, medical, and biotechnology industries and market. HOLOEYE SYSTEMS can provide LCOS microdisplays for versatile applications in the sector of civil defense. The technology is applicable for various augmented reality implementations, e.g. policemen and fire fighters may be equipped with helmet mounted display (HMD) devices, projecting digital data directly in front of their eyes and providing them with mission critical, real-time information (such as maps, navigation or temperature information) at a glance. This technique is also applicable in diving masks, allowing the diver to keep his eyes focused on the dive while presenting critical dive data. The applicability of HOLOEYE's LCOS microdisplays in the aviation industry is virtually unlimited. Applications increase security of air travel and range from helmet displays (to provide the pilot with essential information while keeping his eyes focused on navigating the aircraft) to HUD cockpit applications. One of the most widely-spread optical measurement techniques for 3D-digitizing, 3D-surface inspection, 3D metrology and even etch depth measurement is the fringe projection method: The surface of an object is illuminated with a sequence of fringe patterns. A camera observes the illuminated object and its surface shape is calculated according to the resulting displacement of the fringes. The required fringe patterncan be realized with ultimate precision by using HOLOEYE LCOS microdisplays. This 3D scanning technique has been efficiently used in industrial and life science applications, such as rapid prototyping, reverse engineering, medical imaging etc. HOLOEYE's LCOS microdisplays are ideal for the most advanced medical applications as the new displays provide high-definition images for medical professionals in many fields including endoscopy, radiology, neurology, microscopy and surgery. LCOS displays are ideal for surgeons since they take up so little space but deliver ultra-sharp imaging. In medical equipment HOLOEYE's LCOS microdisplays are also implemented in Near-To-Eye information displays. The surgeon may continue to view the patient anatomy while selected information is superimposed. Examples of such overlays are tumor contours or navigational cues indicating the location of key pathology. Key applications for HOLOEYE's LCOS microdisplays in biotechnology are optical, or laser tweezers and microscopy. Optical Tweezers use a holographic device, such as a LCOS based spatial light modulator (SLM), to sculpt the light from a laser into hundreds of independently controllable optical traps that function like microscopic "tractor beams" to grab any micro- or nanoscale objects, which can then be positioned and moved in three dimensions.

Cable modem

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A cable television system (CATV) distributes broadcast signals from a headend, which is a center of a CATV provider, to subscribers via trunk lines and branch lines, which are configured in a tree structure or in a star structure. The trunk lines and branch lines are used for transmission of broadband broadcast signals, and are implemented by using a coaxial cable or an optical fiber cable. With the explosive growth of the Internet, many customers have desired to use the larger bandwidth of a cable television network to connect to the Internet and other computer networks. In response to the bandwidth limitations of general modem connections, the industry is now turning to alternative methods of connecting to the Internet. A popular alternative to the general modem-type connection is the cable modem (CM) technology which utilizes the cable television infrastructure to transmit and receive Internet related data from a home-computing source. As an alternative to using telephone lines, the Internet can be accessed through coaxial cables using a cable modem. Coaxial cables provide greater bandwidth than home telephone lines and are widely available to existing cable television subscribers. The greater bandwidth also enables new applications such as telephony-over-cable that are not necessarily associated with the Internet. Cable modems can achieve data-transfer rates of up to 40 Mbits/s by connecting directly to coaxial lines as opposed to dial-in modems, that use twisted-pair copper telephone lines. A cable modem receives and transmits data in the form of digitally encoded radio frequency transmissions, which typically travel to and from the cable modem on coaxial cable. In a typical configuration, a personal computer is equipped with a cable modem that interfaces with an existing coaxial cable used to provide cable television service to the home. This coaxial cable is then used to transmit both Internet and television signals to the home. Cable modem systems typically include one or more head ends or cable modem termination system (CMTS) devices that engage in bidirectional communication with the various subscribers' cable modems. Both the cable modems and the CMTS devices include modulators to transmit data, as well as demodulators to receive and demodulate the incoming data. A cable modem network consists of a number of cable modems in subscriber homes, a cable modem headend system, and a coaxial or hybrid-fiber/coax communication link between the headend and the subscriber modems. Unlike traditional dial modems, cable modems transmit and receive digital signals at radio frequencies. A cable modem is equipped on its back with a radio-frequency (RF) coaxial connector for connection to a CATV trunk line, an Ethernet connector or jack for connection to a PC or the like, a universal serial bus (USB) connector or jack, a reset switch to return the modem to its initial state, and a power supply connector to receive electric power.

DDR SDRAM (DDR RAM)

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A double data rate (DDR) synchronous dynamic random access memory (SDRAM) is a memory device which inputs and outputs data by synchronizing the data with a rising edge and a falling edge of a clock signal, and is provided with a data input device and a data output device which operate in synchronization with the rising edge and the falling edge of the clock signal. Dynamic random access memory (DRAM) is an important device, which saves digital data. A synchronous dynamic random access memory (SDRAM) is one kind of DRAM that is synchronized with operation speed and clock signal. In order to further improve the operation speed, a concept of a DDR SDRAM has been extensively used. The term "double data rate" means that the peak data rate is twice the rate at which commands may be clocked into the device. Commands are received as input on the positive edges of the memory clock, while the data is read or written on both the positive and negative edges of the memory clock. DDR SDRAM is structured and functions similarly to regular SDRAM, but doubles the bandwidth of the memory by transferring data twice per cycle. The double data rate operation utilizing the rising and falling edges of the DQS signal is usually performed only in the input/output buffers of a DDR SDRAM. The internal operations of a DDR SDRAM are performed at an interval of one clock. DDR SDRAM use a source synchronous interface for reading and writing data. The source synchronous clock strobe on DDR SDRAM is named DQS. When a double data rate (DDR) SDRAM performs a write operation, the DDR SDRAM latches data at a rising and a falling edge of a DQS signal, and thus operates twice as fast as the frequency of a clock signal CLK. That is, it operates at double data rate.

Integrated circuit (IC), electronic circuit

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Semiconductor integrated circuits (ICs) are typically formed on a section of a wafer of semiconductor material, such as silicon. The wafer includes multiple sections where each section is called a die. Integrated circuits (ICs) include transistors and capacitors integratedly arranged in one semiconductor chip. Integrated circuits may include at least two circuit components that are formed on a common semiconductor substrate and which each have self-contained supply voltage systems. In addition, each of the two circuit components may include self-contained bonding spots for receiving an externally supplied voltage. Most integrated circuits contain one or more output transistors that control current flow through one or more external loads. Integrated circuit packages are utilized to enclose, protect and isolate integrated circuits from potentially hazardous mechanical and environmental elements which may cause damage or destruction. Integrated circuit devices that are typically encapsulated in such packages may include high density memory array devices, logic devices, processing units, microcontrollers, communications controllers and associated input and output structures. The packages also provide a robust and rugged platform for operational needs of integrated circuits, including heat transfer, structural stability and electrical connections. An application specific integrated circuit (ASIC) is a specialized integrated circuit that is designed for a particular application and can be implemented as a specialized microprocessor. Application specific integrated circuits (ASICs) offer the electronics designer the ability to customize standard integrated circuits (ICs) to provide a unique set of performance characteristics by integrating complex functionality and input/output (I/O) on a single integrated circuit (IC). Many different ASIC technologies are available, including gate array, standard cell, full custom design, and programmable logic devices. Programmable devices are a class of general-purpose integrated circuits that can be configured for a wide variety of applications. Such programmable devices have two basic versions, mask programmable devices, which are programmed only by a manufacturer, and field programmable devices, which are programmable by the end user. Programmable chips differ from ASICs because of their ability to implement any number of different complex digital logic circuits by configuring the underlying integrated chip. Programmable devices can be categorized as programmable memory devices or programmable logic devices. Programmable memory devices include programmable read only memory (PROM), erasable programmable read only memory (EPROM) and electronically erasable programmable read only memory (EEPROM). Programmable logic devices include programmable logic array (PLA) devices, programmable array logic (PAL) devices, erasable programmable logic devices (EPLD) devices, and programmable gate arrays (PGA). A field programmable gate array (FPGA) is an integrated circuit (IC) that includes a two-dimensional array of general-purpose logic circuits, called cells or logic blocks, whose functions are programmable. The field programmable gate array (FPGA), typically includes an array of programmable tiles. These programmable tiles can include, for example, input/output blocks (IOBs), configurable logic blocks (CLBs), dedicated random access memory blocks (BRAM), multipliers, digital signal processing blocks (DSPs), processors, clock managers, delay lock loops (DLLs), and so forth. FPGAs can be designed using a variety of architectures which can include user configurable input/output blocks (IOBs) and programmable/configurable logic blocks (PLBs/CLBs) having configurable interconnects and switching capability. The advancement of computer chip technology has also resulted in the development of embedded processors and microcontrollers. An embedded processor or controller can be a microprocessor or microcontroller circuitry that has been integrated into an electronic device as opposed to being built as a standalone module or plugin card. A system-on-chip (SoC) is a fully functional product having its electronic circuitry contained on a single chip. SOC data processors are characterized by a very high degree of integration on a single integrated circuit (IC) chip. While a microprocessor chip requires ancillary hardware electronic components to process instructions, a SoC can include all required ancillary electronics. In general, microprocessors are often preferred when flexibility and variable control are key design considerations. ASICs are often selected when performance or small circuit size is essential. FPGAs are often used when programmability and performance are important. A phase locked loop (PLL) implemented with an integrated circuit (IC) provides an efficient tool in implementing high-frequency components for radio transceivers in telecommunication systems. A typical phase locked loop includes a voltage controlled oscillator (VCO), a control unit, and a detector unit. Phase-locked loop (PLL) circuits have been one of the basic building blocks in modern electronic systems. They have been widely used in communications, multimedia, and other applications. Frequency synthesizers, FM demodulators, clock recovery circuits, modems, and tone decoders are some applications for PLL circuits.