Glossary

Fibre Optics

Is a method of modulating video, audio or data with a light beam and transmitting it along a glass core.

Field

Is one half of a frame and consists of 312.5 (PAL) and 262.5 (NTSC) lines. Odd and even fields are combined to form a single frame.

Field of View

Is the height and width of the view that can be seen through a lens.

Fixed Lens

Is a lens with a fixed focal length. A wide range of fixed lens are available to suit different applications eg 2.6 mm, 4.8 mm, 8 mm, 16 mm, 25 mm and 75 mm etc.

Flexible Conduit

Is a flexible PVC conduit which is used at the camera point to enclose loose cables between the camera and the junction box or wall.

Fluorescent Lamp

Is a type of artificial light source in which the mercury vapour gener- ated by a low wattage arc strikes the phosphor material to emit light. It is popular in indoor applications.

Fly Back Period

Is the time taken to move from the end of a field, frame or line to the start of the next field, frame or line. It is also called the retrace period.

Focal Length

Is the distance between the optical centre of a lens and the point of focus. It is usually measured in mm.

Focus Ring

Is a ring on a lens which is rotated to obtain correct focus.

Frame Interline Chip

Is a type of CCD chip which is expensive to manufacture and is cur- rently used in broaDCasting video cameras. It overcomes many short- comings of the existing CCD chips used in CCTV cameras.

Frame Switching

Is a process used in multiplexers or multi-recorders in which a frame is picked up from each camera in turn.

Frame Store

Is an electronic device used to capture and digitally store a video image. It can be an independent unit or inbuilt in other equipment like fast scan video transmitters or video motion detectors.

Frame Transfer Chip

Is a type of CCD chip in which the pixels have a dual role of sensing the light and transferring the charge. This causes picture smearing, a major shortcoming of this chip.

Frame

Is the basic unit of a moving picture. A frame contains 625 lines (PAL) or 525 lines (NTSC).

FSK

Frequency shift keying - Technology to transmit digital information over a telephone line. The information is translated into an audible signal.

Galvanometer

Is a type of auto iris lens in which the DC motor drive is contained in the camera rather than in the lens. This lens is cheaper but it cannot be used with cameras which do not have this inbuilt DC motor drive.

Gamma Correction

Is a correction built into the camera to adjust for the brightness char- acteristics of the monitor. The gamma value ranges from 0.45 to 1.0.

Geometric Distortion

Is an error which causes the reproduced picture to be geometrically different from the original picture.

Ground Loop Current

Is an AC current produced in a video cable when the two ends of the cable do not have the same ground potential.

Ground Loop Insulator

Is an isolation transformer which can eliminate ground loop currents by removing any direct connection between the inputs and outputs.

GUI Graphical User Interface

Interfaces the computer with the matrix switcher. Hot areas on the computer screen can be programmed to activate a matrix switcher, VCR etc. It helps in making the CCTV system more user friendly.

Halogen Lamp

Is a type of incandescent lamp with a good spectral response. It is used in flood lighting of sports stadiums.

Hertz

Is a unit of measuring frequency. 1 Hertz = 1 cycle per second.

Horizontal Resolution

Is the number of vertical lines which can be resolved in a picture. It depends upon the number of pixels in a chip.

Horizontal Shift Register

Is a part of the CCD chip to which the charge from the pixels is trans- ferred line by line. This charge is then converted into an analogue video signal.

Illuminance

Is the amount of luminous flux falling on a surface area and is mea- sured in lux.

Image Intensified Camera

Is a type of camera coupled with an image intensified tube which generates additional photons. This tube allows the camera to be used in low light areas.

Image Intensifier

Is a device which intensifies light by using light sensitive phosphor screens. It is used to improve camera performance under low light conditions.

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© Siemens Building Technologies Group

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Siemens CRT, TFT manual Fsk
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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.
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