Glossary

Twisted Pair Cable

Is a type of balanced cable in which a pair of cables are twisted and the signal is divided between them.

Two Speed Recorder

Is a domestic VCR which has two speeds of recording/playback, stan- dard and long play. The long play mode doubles the recording time of a standard tape.

Ultraviolet

Is electromagnetic radiation with a wavelength of less than 400 nm and is not visible to the human eye.

Unbalanced Cable

Is a type of cable in which the ends of the shields are grounded to different equipment with possibly varying ground potential. This unbalanced set up can give rise to ground loop currents and EMI induction.

UPS

Uninterruptible Power Supply stores electricity and supplies power to a CCTV system during a power failure.

Usable Video

Is the minimum video signal specified in the camera data sheet to generate an acceptable picture on the monitor. It is usually mea- sured as a percentage of the full video.

Varifocal Lens

Is a type of manual zoom lens with a small zoom ratio (ranging between 3.5 mm to 70 mm depending on brand). It is used when the focal length of the lens needs to be fine tuned to meet the requirements of the actual scene.

Video Head

An internal part of a VCR which rotates very rapidly and writes the video signal on to the video tape during recording while reading the video signal from the tape during playback.

Vertical Resolution

Is the number of horizontal lines which can be resolved in a picture. It is limited by the television scanning method - NTSC, PAL etc.

Vertical Shift Register

Is a part of the interline transfer of a CCD chip , it is placed in between every column of the pixels. At the end of each frame the charge from the pixels are sent to the vertical shift register (VSR) and then row by row to the horizontal shift register.

Vertical Streaking

This type of picture distortion occurs due to overloading of the pixels in an interline transfer chip. It appears as vertical streaks above and below the bright part of the picture.

VHS

Video Home System is a type of popular recording format used in video cassette recorders.

Video Amplifier

Is used to boost the strength of a video signal.

Video Cassette Recorder

Is a device which can record (or playback) video and audio signals on a magnetic tape housed in a cassette.

Video Distribution Amplifier

The video distribution amplifier is used not only to boost the strength but also create multiple outputs of the video input signal.

Video Intercom

Is a door entry system which uses both audio and video to communi- cate and/or control movement of people.

Video Monitoring

Is an application which uses video to monitor remote sites in any part of the world. The video images are transmitted through the tele- phone network.

Video Motion Detection

Is a means which can detect change in the pixelation or movement in the picture and then generate an alarm.

Wattage

Is a unit of power measured in watts (W).

Wave Length

Is the distance travelled by an electro magnetic wave during one cycle.

Wide Angle Lens

A type of lens which gives a wide view of the scene and has a magni- fication ratio of less than 1.

Wide Dynamic Range

A camera with wide dynamic range is able to improve the image quality. It corrects too bright and too dark areas of the scene.

Zoom Lens

 

A type of lens with a variable focal length ranging from wide angle to

 

telephoto.

 

Zoom Ratio

16

Is the ratio between the maximum and minimum focal length of a

 

zooms lens.

© Siemens Building Technologies Group

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Siemens TFT, CRT manual Ups

CRT, TFT specifications

Siemens, a prominent name in electronics and engineering, has made significant contributions to display technology, particularly in the realms of Thin Film Transistor (TFT) and Cathode Ray Tube (CRT) displays. These technologies have paved the way for advancements in visual media, ranging from television sets to computer monitors.

TFT display technology, a type of LCD (Liquid Crystal Display), employs thin film transistors to produce brighter and more vibrant images. One of the main features of TFT displays is their ability to deliver high resolution and excellent color reproduction, making them ideal for various applications such as smartphones, tablets, and laptops. TFT screens utilize an active matrix approach, which allows each pixel to be controlled individually. This method results in faster response times and improved image quality, with less motion blur, compared to older passive matrix displays.

One of the key characteristics of TFT technology is its versatility in different settings. It supports a wide range of viewing angles, which enhances the user experience whether one is viewing the display head-on or at an angle. Additionally, TFT displays are known for their thin profile and lightweight design, contributing to the overall portability of devices that incorporate them.

On the other hand, CRT technology, which was once the standard for televisions and computer monitors, uses electron beams and phosphorescent screens to produce images. One of the defining features of CRTs is their ability to display deep blacks and a wide color gamut. CRT technology can achieve high refresh rates, reducing flicker and improving the quality of fast-paced visuals. However, CRTs tend to be bulkier and heavier than modern display technologies like TFT.

Despite the evolution towards flat-panel displays, CRT technology is still appreciated for its natural color and motion portrayal. Siemens has leveraged these characteristics to produce quality CRT monitors that were favored in professional settings, including graphic design and medical imaging, where color accuracy is paramount.

In summary, Siemens has played a vital role in advancing both TFT and CRT technologies. TFT displays are recognized for their high resolution, fast response times, and design versatility, while CRTs are celebrated for their rich color and depth. As technology continues to advance, the legacy of these display types remains influential in shaping modern electronic devices.