Siemens CRT, TFT manual Ntsc

Models: CRT TFT

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Glossary

Lux

Is an international unit of illumination. It is the amount of uniform light falling on an area of 1 square metre and is measured in lumen per sq metre.

Magnification Ratio

Is the ratio between the focal length of a lens and the focal length of a standard angle lens. It indicates the magnification of the image on the monitor as compared to the image seen by a standard angle lens.

Matrix Switcher

Is a type of switcher which allows a single input to be switched to many outputs. Matrix switchers are used in large CCTV systems and have many powerful features.

Mercury Vapour Lamp

Is a popular type of artificial light source which emits a blue-white light. Used extensively for commercial lighting.

Microwave Links

Is a type of transmission medium in which video, data or audio is modulated with a microwave frequency and then transmitted to a receiver in a remote location over free space.

Mimic Panel

Is a panel which shows the layout of a site with the camera positions highlighted. By interfacing it with a CCTV system, the operator can switch any camera to the monitors from the mimic panel itself.

Minimum Scene Illumination

Is a specification shown in most camera data sheets and indicates the minimum light required at the scene to provide a reasonable pic- ture on the monitor.

Modem

Is derived from the term 'modulator -demodulator' and is used to convert a digital signal into an analogue signal so that it can be transmitted via the PSTN telephone network.

Modulate

A method in which a signal to be transmitted is mixed with a high frequency carrier signal.

Motorised Controlled Iris

Is a type of iris control in which the iris motor is controlled from a remote location, usually in a zoom lens.

Multi Core Cable

Is a type of cable which has many cores enclosed in one outer jacket. In CCTV it is normally used to transmit control signals.

Multimode Cable

Is a cheaper type of fibre optic cable which allows a light beam to travel by more than one path thus causing transmission distortion.

Multiplexing

Is a process whereby many cameras are switched frame by frame. This frame switching can be used in applications like multi-viewing, multi-recording etc.

Neutral Density Filter

Is a type of filter used with lenses which reduces light of all wave- lengths equally.

Noise

Is an unwanted signal generated by every electronic component. The noise in a video signal causes a grainy or snowy effect on the image.

NTSC

National Television System Committee is a colour television system and the standard used in the USA and Japan. NTSC has 525 horizon- tal scanning lines and 60 fields per sec.

Ohms

Is a unit for measuring resistance or impedance of any electrical device.

Omni Directional Transmitter

Is a transmitter which sends the signal in all directions.

Optical Filter

Is a type of filter used in optics which selectively allows light of dif- ferent frequencies to pass through.

Oscilloscope

Is a device which visually displays the wave form of any electrical sig- nal on a screen. In CCTV, it is used in trouble shooting and making adjustments of various components.

PAL

Phase Alternating Line is a colour television system and the standard used in Western Europe, Australia, parts of Africa and Asia. PAL has 625 horizontal scanning lines and 50 fields per sec.

Persistence of Vision

The retina of the human eye retains an image for 40ms. This charac- teristic is called “persistence of vision” and is used to make a picture appear continuous by flashing images on the retina at a rate faster than 24 images per sec.

Phase Adjustment

Is a camera adjustment used to synchronise all the cameras in the system by altering the phase of the power supply.

Phase Angle

Is the angle at any point of the sine wave of an AC power supply and varies between 0 to 360 deg over a cycle.

Phosphor

Is a material which is capable of emitting light. It is used in fluores- cent lamps, monitors etc. The duration of the emission depends on the type of phosphor.

Picture Tearing

Occurs when the horizontal sync pulses are distorted or lost and the monitor is unable to latch on to them causing the horizontal lines to be displaced in a random manner. This is seen as a tearing of the pic- ture on the monitor.

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© Siemens Building Technologies Group

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Siemens CRT, TFT manual Ntsc

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.