DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN

"Quantum dots" - new improvement in CMOS technology.

Image sensor is the element of cameras which converts the image projected onto it by the lens into electrical impulses. Currently, there are two main matrix (array) technologies, CCD and CMOS. CMOS sensors are much less expensive to manufacture, while the CCD sensors have a much greater sensitivity and mechanisms for extending the dynamic range of an image.
The latest development of the InVisage Technologies company may change this view. Its QuantumFilm image sensors employ the recent developments in nanotechnology, particularly the phenomena taking place in so-called "Quantum dots" - ultra-thin semiconductor layer with unique light-capture properties. Quantum dots is an integrated thin film of thickness several to tens of nanometers, divided into cells ( "dots") of similar dimensions. It is worth to note that the wavelength of visible light ranges from 400 to 700 nm and 1 nanometer is one millionth of a millimeter.

QuantumFilm layer in the CMOS sensor

The principle of operation of image sensors is to capture photons increasing the energy of electrons. The QuantumFilm makes the process more efficient. The "quantum dot" size and thickness are so small that they restrict the free movement of atoms. Using the analogy of shooting - the photons shoot into a fixed target, instead of a constantly vibrating one, in a chaotic manner.
The use of "quantum dots" technology as an additional layer - QuantumFilm formed on the CMOS sensor - reduces the loss of photons, which amounts to 5-10% (instead of usual 75% in a regular CMOS sensor). This way the sensor captures nearly 4x more light, i.e. 90-95% of the total amount. It allows to produce images even in very difficult lighting conditions. This high efficiency translates directly into increased resolution and sensitivity of the sensor, despite its small size.

The idea of QuantumFilm sensor
(source: http://www.invisageinc.com )

QuantumFilm can be ideal solution for a wide range of imaging equipment. In addition, QuantumFilm has been designed based on the already manufactured CMOS sensors, therefore, the implementation of the new technology will require only a slight adjustment of the production line. In the near future we may be witnessing a true revolution in cameras of mobile phones (at the end of 2010), and then in CCTV as well as in webcameras, automotive and still cameras.

Quantum dots can be a real breakthrough in medicine. They can serve as markers in diagnostics, as well as can deliver microscopic portions of medicines to sick cells - particularly promising results can be expected in oncology.

QuantumFilm sensors have a chance to dominate the market

Quantum dots technology is one of the most promising ones. Through its application it is possible to build not only new sensors, such as QuantumFilm, but also light sources with a much greater efficiency, including lasers.

Birds in the forest of antennas.

Increasing urbanization reduces the natural habitat of animals. Many animals must adapt to the new environment. Birds adapt relatively easily, making use of the man-made structures as the places to rest, and even to nest.
We invite you to participate in the contest "Engagingly about antennas ". The works can be submitted from June 1st, however the pictures can be taken during any season of the year - just look for an interesting topic!

DVB-T antenna ideal for installation on facades.

Signal HDA-5000 A6040 antenna is designed to work outdoors. Due to special design and application of high-quality low-noise amplifier, it provides very good results in receiving digital terrestrial television (DVB-T). The antenna can receive signals in both vertical and horizontal planes. It has an integrated GSM/3G filter. The antenna comes with a set of accessories allowing to mount it on a pole or a building facade.
The antenna can be powered directly from the DVB-T receiver (usually a Set-Top-Box), or (when the receiver does not supply 5 VDC at its RF input) from the included AC/DC adapter (9 VDC output) and DC injector.

Moisture-resistant cable - TRISET-11 PE Total Cu.

The inner conductor, foil and braid of TRISET-11 PE Total Cu E1029 are made of copper, which allows to use the coaxial cable in wet environments - there is no risk of corrosion due to presence of water (typical for aluminum). The cable is protected by PE (polyethylene) sheath. It is used for relatively long trunk lines (of SMATV/MATV/CABLE systems) and for interconnection of subnetworks, especially when the cable has to be buried in the ground. Of course, the cable has to be protected against mechanical damage.
The TRISET-11 Total Cu, similarly to the whole TRISET family, is characterized by perfect shielding (better than 100 dB) and high return loss (20 dB on average).
To complete an installation professionally, there are needed proper connectors. For the TRISET-11 PE Total Cu we recommend compression F connectors from PCT - DRS-11QP (E80360) and universal compression tool (BNC, F, IEC, RCA) - PCT-AIO-CT (E80075).

5 ohm coaxial cable TRISET-11 PE Total Cu 1.65/7.2/10 E1029

Size of an object on monitor screen.

According to standard EN 50132-7, the size of the representation of an object, e.g. human figure should be strictly connected with the aim of the operator - identification, recognition, detection or general observation. For CCTV systems having resolution better than 400 TVL, the representations of human figures should not be smaller than:

The size of human figure on monitor screen as a function of the aim of monitoring system

A new generation of infrared illuminators - part 1.

Infrared illuminators are essential accessories used in CCTV systems. They allow to light the monitored area in the dark, using infrared light which is not visible to the human eye (it may depend on the wavelength), but is perfectly captured by CCTV cameras.
The advantage of the Redbeam series is application of specially designed LED matrix (instead of a conventional set of diodes) which, together with optical lens/es, ensures desired operational angle and distance.
Along with a day/night camera, the illuminator makes a perfect tool for monitoring at night. Twilight sensor in combination with high-efficiency IR LEDs can provide very good results with relatively low power consumption.

A typical IR LED provides output power between 5 mW and 15 mW, so, even in the case of short operational distance, an IR illuminator has to employ at least several such diodes. LED matrices provide output power between 1000 and 2500 mW. This means a much longer range, in spite of the small size of the device.
To make an IR illuminator of the same power, one would have to use a large number of typical IR LEDs and its size would be much greater. For example, an1500 mW illuminator should consist of 100 LEDs of 15 mW output power. Of course, such a solution is feasible, but the illuminator would be much bigger than a similar Redbeam device.
The matrix of small size makes it easy to shape the beam with lenses. In the case of a traditional IR LED illuminator, the angle of the beam depends on the arrangement of LEDs, which is not a flexible solution. Using a LED matrix, virtually any angle can be achieved. The examples are the dome models M1642 and M1643, with beams of 180^o (in vertical plane).

Another advantage of the matrices is the lifetime of the materials used. Standard heavy-duty IR diodes operate around 6000 hours. In the case of the matrices, the expected lifetime is about 50000 hours. It means that they can work for over 10 years (12/24 cycle)!

CCTV system in an elementary school.

One of elementary schools in southern Poland decided to install a video monitoring system. The reason was numerous acts of vandalism and hooliganism - destruction of school property, robberies on students, thefts from the locker room. The teachers and other staff were not always able to personally oversee the conduct of over 500 students in the school.

Because the school had limited funds, the installation company had to choose equipment that was both cheap and reliable. There was no chance to employ a security guard - the task of the operator at the reception was to be performed by the school janitor.
The system has been based on Ultimax DVRs (Ultimax-104 M71040) and Ultimax-Hikvision DVR - DS-7316HI-S M74160. The two M71040 DVRs cooperate with vandal proof color CCTV cameras V-CAM 515 + IR, deployed around the school. Inside the school there are color cameras Cam-665 Roto M11252 in ceiling housings with IR illuminators (less risky places) and color vandal proof cameras SN-VP3050 + IR M11254 (in more vulnerable locations). All the indoor cameras are connected to the single 16-channel DVR DS-7316HI-S M74160. In total, the system uses 24 cameras.

Block diagram of the system

The DVRs have been connected to the school LAN. The images are displayed at the reception and on other software-defined computers, using free network client software iVMS4000. The access to the images is protected by logins and passwords. The operation of the system is extremely simple and intuitive - after a short training the teachers and school administrative staff can easily access the video coverage. Low costs of the system and its high protection level are the reason that many other schools and institutions are interested in similar solutions.

WLAN in a single-family house - part 1.

The user who has Internet connection in their single-family house, usually would like to have possibility of using the Internet in various parts of the home or even in its close surroundings like garage or garden. To reach that goal, the perfect solution is use of a wireless network (WLAN) operating in 802.11b/g or the latest n standard. Depending on the way of providing the Internet to the house, there may be used different variants of installations. They will be successively described in the Newsletter.

Variant I - Internet provided by a cable television operator via cable modem with Ethernet output, or by a local ISP using Ethernet cable.

In these cases one needs a router with WAN input (RJ-45 Ethernet port), e.g.:

Internet access via Ethernet cable

These devices allow to connect 4 computers (using Ethernet patch cables) and up to a dozen other computers - using wireless connection.

We have written about:

Quick adapter to DC 2.1/5.5 power connector and professional compression BNC connector. S-55 quick adapter (E3511) and BNC connector E8282 are indispensable accessories for professional installers of CCTV systems. The quick adapter ensures easy and stable connection of power cable to any CCTV camera. To mount the plug, the installer should strip the wires, push them into terminals and tighten the two screws with a screwdriver...

ULTIMODE optical converters. DIPOL introduces video converters of ULTIMODE 20x series (the x figure indicates the number of video channels) allowing to transmit video and audio, as well as alarm and control signals.
Below there is an example of application of ULTIMODE V-204DAO L2423 which converts into optical signals 4 video channels, 1 data channel, 1 audio channel, and alarm signal. The information can be transmitted via single optical fiber over distances up to 20 km...

Efficient wireless transmission in 5 GHz band with the use of ULTIAIR devices. Implementation of a base station with the possibility of connecting a large number of users requires the investor to use professional equipment. The equipment must be characterized by high efficiency, allowing for seamless transmission of large amounts of packages and uninterrupted transmission. The ideal solution is application of ULTIAIR family. The devices of the family are designed for efficient long-term outdoor operation and allow to create professional wireless IP CCTV and ISP networks...

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