Color LCD monitors.

Color LCD monitors.

Today, there is practically no well-known manufacturer of video surveillance monitors whose lineup does not include LCD monitors specially designed for use in video surveillance systems — CCTV. Indeed, the best models of LCD monitors of all brands meet the high requirements for video surveillance monitors. In particular, the video signal output to the monitor in real time must be clear, have natural color rendition, not be distorted or blurred with a rapid change of frames.
Modern LCD monitors are free from the disadvantages of cathode-ray monitors due to the use of technologies that do not use electron beams, high voltage and phosphors.
LCD monitor production technologies are constantly being improved, and the technical characteristics of the screens are improved every six months. In addition, these monitors are compact, serve for at least 6-7 years, are easy to set up and operate, are insensitive to electromagnetic fields, are ergonomic, can be quickly mounted in a rack or on walls, and have low power consumption. However, when choosing a monitor for a video surveillance system, the decisive factor is the technical, operational and ergonomic requirements.

Resolution and color rendering of LCD monitors
Resolution is one of the main characteristics of a CCTV monitor. This parameter is determined by the maximum number of displayed transitions from black to white and is measured in television lines (TVL). However, LCD monitors are fully digital devices for which resolution is measured by the number of pixels vertically and horizontally, so for such monitors the estimated resolution is indicated in TVL. For example, for the JVC LM-17G CCTV monitor, the resolution of 1280 by 1024 pixels indicated by the manufacturer corresponds to 500 TVL. Their color rendition corresponds to the color space visible to the human eye, since these monitors can reproduce 16.7 million shades.

Brightness and contrast of LCD monitors
The brightness of such a monitor is determined by the brightness of the backlight and the throughput of the screen filters. Thus, a brightness level of 250 cd/m2 is high enough for LCD monitors and allows you to see a contrast image even in a brightly lit room. The contrast ratio of the monitor is associated with the contrast ratio, which corresponds to the difference between the brightness of white and black test rectangles. The higher the contrast ratio, the more natural and saturated the color image will look. Modern LCD monitors for CCTV have a contrast ratio from 200:1 to 400:1.

Flat LCD monitors feature a large viewing angle and image size
The maximum viewing angle of a liquid crystal monitor is the extreme value at which the contrast ratio decreases to 10:1 from the standard value corresponding to the observer's perpendicular position to the screen plane. All modern LCD monitors designed for video surveillance systems have a viewing angle of 160–170 degrees, which allows security personnel to see the image on the monitor without loss of quality even when the LCD monitor is at an angle to the operator. The specified diagonal size of a flat monitor coincides with the diagonal of the visible area of ​​the image.

Response time of LCD monitors
The response time of a pixel of a liquid crystal monitor matrix or the duration of a pixel refresh is the time it takes for a pixel to change color. The response time of modern industrial LCD monitors with an analog video input is between 10 and 35 ms, which may be quite sufficient for displaying a video signal in real time at a frequency of 25 frames per second. At the same time, response time measurement technologies vary greatly among different manufacturers and may diverge from the results of empirical measurements.

LCD monitors have several mounting options
LCD monitors can be installed either on a table using a special stand, or mounted on a wall or in a standard 19-inch rack. For example, many companies' monitors have four VESA mounting holes with a pitch of 100 mm on the back panel, as well as four through holes in the corners of the monitor case for various mounting options. Quick mounting, a flat and lightweight case allow using LCD monitors to create monitor video walls in control rooms or security service rooms.

LCD monitors have analog and digital inputs
Being digital devices, LCD monitors can operate in both analog and digital video surveillance systems. To receive an analog video signal, monitors are usually equipped with two (less often one) protected BNC video inputs. In addition, any LCD monitor has a standard 15-pin digital input, which allows you to connect the monitor to a computer of a digital video surveillance system. Some monitors have an audio system for receiving and playing an audio signal.

Ergonomics of LCD monitors
One of the main advantages of an LCD monitor is that it is absolutely safe for humans, does not cause fatigue, does not injure the eyes and allows for more comfortable working conditions for operators, which has a positive effect on the efficiency of the security service. As studies show, the human eye finds the information it is interested in on an LCD monitor faster than on a CRT, and makes mistakes less often. In addition, the spectrum of frequencies emitted by an LCD monitor is close to visible sunlight, and such a monitor fully meets the requirements of all known safety standards (in particular, TCO’99) and has low power consumption (35–45 W).

LCD monitors have a service life of 6–7 years
For the TFT matrix of the monitor, there is no technological problem of screen burn-in when projecting static images. The service life of LCD monitors for video surveillance is currently 6-7 years without loss of quality. Liquid crystal monitors are more suitable for creating monitor video walls, which allows increasing the space in the security service premises, and in the case of increased requirements for the ergonomics of the operator's workplace, LCD monitors have a significant advantage.

Acumen Ai-ML177N (Acumen) Monitor
The Acumen Ai-ML177N 17-inch monitor is designed for use in medium and large-scale video surveillance systems. This monitor reproduces 16.2 million colors at a resolution of 1024 x 768 pixels, providing a clear image without distortion. It has a highly efficient video processor, as well as the maximum response speed of the LCD cell. The metal case of the Ai-ML177N monitor protects the electronics from electromagnetic interference and ensures stable video image quality. And the 3D-Y/C filter provides a clear image without blurring and shaking. The monitor has a deinterlacing filter that prevents the «interlace» effect that occurs when two half-frames are combined into one frame. Which is important when you need to fix a separate frame.

LCD monitor GD-171 with SXGA resolution and 3D Comb filter (JVC)
The compact 17-inch GD-171 monitor is designed for pendant/desktop installation and 24/7 operation. It displays video with SXGA resolution (1280 x 1024) in 5:4 format, has an anti-glare surface, 170°/160° viewing angles and transmits high-quality dynamic video due to the use of an LCD matrix with a pixel response time of 5 ms. The GD-171 reproduces 16.7 million color shades, has a contrast ratio of 800:1 and uses a 3D Comb filter, which improves image quality by separately processing brightness and color signals. For connecting external devices, there are two BNC video inputs, an S-Video (Y/C) input and analog RGB, as well as an audio input/output. The front panel has control buttons for adjusting all monitor parameters via the on-screen menu. The GD-171 is equipped with 2 speakers, housed in a case with a VESA 100 wall mount and a very thin frame, and comes with a stand that allows you to adjust the angle.

High-contrast 17″ PMCL300 series monitor with 5:4 aspect ratio and 5 ms response time (Pelco by Schneider Electric)
The ergonomic LCD monitor PMCL317A by Pelco by Schneider Electric is part of the professional PMCL300 series for video monitoring systems. It uses an active TFT matrix with a 5:4 format, 160° viewing angles and a response time of at least 5 ms, forms an image with a resolution of SXGA and 16.7 million colors, while it has a brightness of 300 cd/m2 and a contrast of 1000:1. Displaying signals from various sources is possible due to the presence of composite BNC and S-Video, as well as RGB and DVI inputs — the electronics automatically adjust to the resolution of the received video signal. Reception and reproduction of sound are provided by 2 audio inputs (RCA, PC) and stereo speakers. The PMCL317A has 4 CCFL backlight lamps to transmit a rich picture in strong ambient light, and image parameters can be adjusted from the front panel. The model has a thin metal case, low power consumption and can be installed on a table, wall or rack.

PMCL417A (Pelco by Schneider Electric)
The Pelco PMCL417A monitor is a classic example that meets all security system requirements. It is designed for long-term round-the-clock use (lifetime of at least 50,000 hours). The monitor case is made of steel. Brightness of 450 cd/m2, contrast of 1000:4, response time of 4 sec. and viewing angle of 160 degrees make this monitor an excellent and convenient assistant for a security guard.
The monitor has a large number of video inputs (2 through BNC, 1 through S-video, 1 RGB and 1 DVI), numerous brackets for wall, rack or ceiling mounting are available as an option.

Budget 17-inch LCD monitor STM-173 with 3D deinterlacing function (Smartec)
The image on the STM-173 Smartec monitor screen is always clear and contrasting, regardless of whether the signal comes from an analog or digital source. It is designed on the basis of an LCD matrix with a resolution of 1280 x 1024 pixels and reproduces 16.7 million shades with a brightness of 300–450 cd/m2 and a contrast ratio of 500:1. The STM-173 uses a 3D deinterlacing function that smooths out interlaced «comb» and makes video frames clearer, has a 4:3 format, a response time of 8–12 ms, a viewing angle of 140°, analog BNC and S-Video inputs, RCA audio input and audio output, as well as a 15-pin D-Sub connector for connecting to a PC. The monitor provides precise and convenient picture adjustment using on-screen menus, comes with a stand, provides various installation options and consumes no more than 50 W and about 3 W in energy-saving mode.

SMT-1722 – 17-inch TFT LCD monitor (Samsung)
The security video surveillance monitor uses Samsung's specialized DNIe (digital image optimization) technology. The monitor has a 17-inch (43 cm) tempered glass screen. In addition to DNIe, it has a double signal processing performance of 100 Hz and has PIP (picture in picture) and PBP (picture by picture) functions. The latter allows you to split the screen into two parts so that the operator can see two images at the same time. The SMT-1722 supports a resolution of 1280 x 1024 and provides an analog signal resolution of up to 620 TVL. The monitor has 3 video inputs (2 BNC and one VGA). Image contrast is 1000:1, brightness is 250 cd/m2. The monitor is compatible with VESA brackets, has a height-adjustable desktop bracket and built-in speakers.

SX-17P (Neovo)
Professional 17-inch monitor for video surveillance systems, equipped with Anti-Burn-in T, Advanced Image PlatformT technologies.
Smart Omni Viewer technology with PIP/PAP, freeze frame and rotation functions provides flexibility in video surveillance. A thin body, closed-loop BNC connectors, VESA mount compatibility and a DC power output make it easy to integrate these monitors into an existing system. The SX-17P monitor has an EcoSmart Sensor for reduced power consumption, a durable metal case and NeoVT protective optical glass.
SXGA resolution 1280 x 1024. Horizontal resolution up to 620 TVL (NTSC), 625 TVL (PAL). Built-in image enhancement system: 3D Comb Filter/deinterlacing/noise reduction. It has 2 BNC inputs and outputs, S-Video, VGA, DVI, audio signal input/output. Support for NTSC/PAL/SECAM video signal standards.