Size
The optimal size of the TV depends primarily on the distance from which it is planned to watch. If the diagonal on the screen is too small, it will be difficult to see the details, you will have to strain; if too large, the image will be much larger than the field of view, which is also undesirable. The best option is the situation when the distance to the TV corresponds to 3 - 4 of its diagonals: for example, for a size of 32 "(80 cm), the recommended distance is about 2.5 - 3 m.
The size of the diagonal of the screen affects both the cost of the TV and its general equipment. So, among models smaller than 32" there are often
TVs without Smart TV and other advanced features; TVs for
32 -
55" can be both quite simple and advanced; and a large screen, more than 55", in most cases is combined with extensive additional functionality.
Now the following popular diagonals are on the market:
32 ",
39 - 40",
43",
49",
49 - 50",
55",
65",
75" and
more than 80".
Curved screen
The presence of a
curved screen in the design of the TV. It is usually assumed that the screen has a concave (relative to the viewer) shape — its left and right edges are closer to the viewer than the middle. It is believed that this form significantly improves perception compared to a flat surface — in particular, it enhances the effect of presence and creates the impression of an image that "surrounds" from the sides. That's why concave screens have long been the standard for high-quality cinemas like IMAX, and more recently have been used in televisions.
However, this form also has a drawback, and a rather serious one: to view it, you must be strictly in the centre, at a certain distance from the screen — otherwise the image will be distorted and the viewing experience will deteriorate. In fact, this means that 1-2 people can comfortably watch a TV with a curved screen, no more — there is simply not enough space for the rest in the zone of optimal visibility.
Curvature radius
Radius of curvature of the curved screen (see above). Specified in millimetres for the radius of a circle which curvature corresponds to the curvature of the screen: for example, 4200R corresponds to a radius of 4.2 m.
The smaller the number in this designation – the more the screen is curved (all else being equal). In general, this parameter is more of a reference and does not play a key role in choosing process: it is selected by the manufacturer so that the screen does not give significant distortion when viewed from the side and at the same time that the curvature is quite noticeable. We only note that the mentioned 4200R are considered to be almost an perfect radius of curvature, however, there are also large indicators — for example, 5000R.
Frame rate
The highest frame rate supported by the TV.
Note that in this case we are talking specifically about the screen’s own frame rate, without additional image processing (see “Index of dynamic scenes”). This frequency must be no lower than the frame rate in the video being played - otherwise there may be jerks, interference and other unpleasant phenomena that degrade the quality of the picture. In addition, the higher the frame rate, the smoother and smoother the movement in the frame will look, and the better the detail of moving objects will be. However, it is worth noting here that playback speed is often limited by the properties of the content, and not by the characteristics of the screen. For example, films are often recorded at a frequency of only 30 fps, or even 24 - 25 fps, while most modern TVs support frequencies of
50 or
60 Hz. This is enough even for viewing high-quality content in HD resolutions (speeds above 60 fps in such video are extremely rare), but there are also “faster” screens on the market:
100 Hz,
120 Hz and
144 Hz. Such speeds, as a rule, indicate a fairly high class of the screen; they also often imply the use of various technologies designed to improve the quality of dynamic scenes.
Dynamic scene index
Dynamic Scene Index (DSI) provided by the TV screen.
DSI is a rather specific parameter that can be called "visible framerate". Its appearance is due to the fact that a high frame rate is highly desirable for dynamic scenes — it provides smooth images and good detail of moving objects. However, for technical reasons, it is not possible to achieve indicators above 200 Hz in most screens. In order to remedy the situation, manufacturers use special technologies that create the effect of increasing the frame rate.
Such technologies may have different names, but they have the same principle of operation — inserting additional frames between the "own" frames of the video being played. And the dynamic scene index describes the overall effectiveness of such technology used in a TV. For example, a DSI of 200 Hz means that the image quality on the screen approximates a frame rate of 200 Hz, although the actual frame rate is often as low as 50-60 Hz.
In the most advanced models, the dynamic scene index can be up to 3000 Hz, and options above 3000 Hz are considered to be
TVs with a high dynamic scene index. However, it is worth noting that such specifications are more of an advertising ploy than a real advantage: in fact, the threshold for human perception is 400 – 500 Hz, a further increase in the DSI does not give a clearly visible improvement in the image.
Wall mount
Most TVs have a VESA wall mount which may vary in size. The basis for such mount is a rectangular plate with four holes for screws in the corners. The main characteristic of such a mount is the distance between the holes — it is measured along the sides of the rectangle and is expressed in two numbers. The original VESA format is 100x100, these mounts are used for most medium-sized LCD TVs. For small screens, 75x75 mounts are provided, for large ones — 200x200 and more (up to 800x400).
However, there are also models that are equipped with a standard (proprietary) mount from the manufacturer. Mostly these are either ultra-thin TVs or designer lines. Anyway, the mount in the kit is suitable only for the selected model.
Power consumption
The electrical power normally consumed by the TV. This parameter strongly depends on the screen size and sound power (see above), however, it can be determined by other parameters — primarily additional features and technologies implemented in the design. It is worth noting that most modern LCD TVs are quite economical, and most often this parameter does not play a significant role — in most cases, power consumption is about several tens of watts. And even large models with a diagonal of 70 – 90" consume about 200 – 300 W — this can be compared with the system unit of a low-power desktop PC.
