Screen diagonal
The screen diagonal is a measure of the size of a screen . It describes the distance between two diagonally opposite corners.
The indication of the screen diagonal is only useful to a limited extent. The advantage of a single measure compared to the common specification of width and height can only be used if all devices in a class have the same aspect ratio , as was common for televisions for a long time. Compared to specifying the image area, the diagonal has the advantage that it can be determined by a single measurement and without a calculation.
In advertising, the screen diagonal is often given in inches , especially for computer monitors and liquid crystal displays . See also dpi .
Use according to technique
With tube monitors (CRT), the screen diagonals are usually specified in two parts as a physical and visible screen diagonal, as part of the tube is always covered for technical reasons. If only one value is given, it usually refers to the physical diagonal.
As the size of tube monitors was not determined by the visible diagonal but by the overall size of the (partly invisible) tube, the comparison value compared to flat screens should generally be reduced by about 5 cm (2 inches). A 48 cm (19-inch) tube monitor corresponds roughly to a 43 cm (17-inch) TFT monitor .
Use by device class
TV
Commercially available television sets are predominantly in the range from 30 cm to 127 cm, with the largest classic tube sets only having a visible screen diagonal of around 85 cm. The specification is also applied to projection screens with higher values. The classic aspect ratio was 4: 3, but today's standard is 16: 9 devices.
In some smaller models, the line between television and computer monitor is also blurred. These models can be used both as a computer monitor (these then also have the usual connections for this) and as a television with remote control and integrated tuner . As a rule, these models are at least HD ready , but mostly capable of Full HD .
Computer monitors
Most computer monitors have a screen size between 48 cm and 71 cm (19 in to 28 in), with the demand for larger devices steadily increasing. Portable 18 cm to 38 cm (7 in to 15 in) and old 36 cm to 43 cm (14 in to 17 in) models are sometimes also smaller, while larger devices are also used for professional, graphics-oriented applications ( DTP , CAD ). Traditionally, the television aspect ratio of 4: 3 was common, but in addition to the more square 5: 4, wider formats such as 16: 9, 16:10, 15:10 (3: 2) are becoming more and more common because they correspond more to the natural field of vision of humans.
Small appliances
There are also devices with screen diagonals below 30 cm (12 in), e.g. B. cell phones, PDAs , hi-fi systems, etc., which do not have or need large displays for energy, space or price reasons.
geometry
Side lengths and area
If the aspect ratio ( a: b , e.g. 4: 3 or 16: 9 ) is known, the side lengths ( w , h ) and the image area ( A ) can be calculated according to the Pythagorean theorem with the diagonal ( d ) :
For example, a 4: 3 screen with a 50 cm diagonal has a horizontal side of 40 cm (= 4 ⁄ 5 50 cm) and a vertical side of 30 cm (= 3 ⁄ 5 50 cm), thus an area of 12 dm² (= 12 ⁄ 25 × 2500 cm² = 40 cm × 30 cm).
pixel
If the resolution ( W = x , H = y ) is known, the size of a screen point ( P ) can be determined accordingly:
- square pixels
- general
Said screen with 50 cm diagonal would therefore with a resolution of 1280 × 960 px px (= 1.23 MPX) square pixels having a theoretical edge length of 5 / 16 millimeters or 312.5 microns, which corresponds to 81.3 px / in (DPI).
If the diagonal is given, the image resolution ( R ), i.e. the number of dots per unit of length (e.g. dots per inch , dpi ), is obtained by an inverse operation:
- square pixels
- general
In the case of two devices with different aspect ratios ( a 1 : b 1 and a 2 : b 2 ), the diagonals ( d 1 and d 2 ) must differ in order to display an image with the same height ( h ) or width ( w ):
- same height
- same width
Comparison table
diagonal | 4: 3 = 12: 9 | 16: 9 | 8: 5 = 16:10 | 5: 4 = 15:12 | 21: 9 = 7: 3 | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
(in) | (cm) | B (cm) | H (cm) | A (dm²) | B (cm) | H (cm) | A (dm²) | B (cm) | H (cm) | A (dm²) | B (cm) | H (cm) | A (dm²) | B (cm) | H (cm) | A (dm²) | |||||
1 | 2.5 | 2.0 | 1.5 | 0.03 | 2.2 | 1.3 | 0.03 | 2.2 | 1.4 | 0.03 | 2.0 | 1.6 | 0.03 | 2.3 | 1 | 0.02 | |||||
2 | 5.1 | 4.1 | 3.0 | 0.12 | 4.4 | 2.5 | 0.11 | 4.3 | 2.7 | 0.12 | 4.0 | 3.2 | 0.13 | 4.7 | 2 | 0.09 | |||||
3 | 7.6 | 6.1 | 4.6 | 0.28 | 6.6 | 3.7 | 0.25 | 6.5 | 4.0 | 0.26 | 6.0 | 4.8 | 0.28 | 7th | 3 | 0.21 | |||||
3.5 | 8.9 | 7.1 | 5.3 | 0.38 | 7.7 | 4.4 | 0.34 | 7.5 | 4.7 | 0.36 | 6.9 | 5.6 | 0.39 | 8.2 | 3.5 | 0.29 | |||||
4th | 10 | 8.1 | 6.1 | 0.50 | 8.9 | 5.0 | 0.44 | 8.6 | 5.4 | 0.46 | 7.9 | 6.3 | 0.50 | 9.2 | 3.9 | 0.36 | |||||
5 | 13 | 10 | 7.6 | 0.77 | 11 | 6.2 | 0.69 | 11 | 6.7 | 0.73 | 10 | 7.9 | 0.79 | 11.9 | 5.1 | 0.61 | |||||
6th | 15th | 12 | 9.1 | 1.11 | 13 | 7.5 | 0.99 | 13 | 8.1 | 1.04 | 12 | 10 | 1.13 | 13.8 | 5.9 | 0.81 | |||||
7th | 18th | 14th | 11 | 1.52 | 15th | 8.7 | 1.35 | 15th | 9.4 | 1.42 | 14th | 11 | 1.54 | 16.5 | 7.1 | 1.17 | |||||
8th | 20th | 16 | 12 | 1.98 | 18th | 10 | 1.76 | 17th | 11 | 1.86 | 16 | 13 | 2.01 | 18.4 | 7.9 | 1.45 | |||||
9 | 23 | 18th | 14th | 2.51 | 20th | 11 | 2.23 | 19th | 12 | 2.35 | 18th | 14th | 2.55 | 21.1 | 9.1 | 1.92 | |||||
10 | 25th | 20th | 15th | 3.10 | 22nd | 12 | 2.76 | 22nd | 14th | 2.90 | 20th | 16 | 3.15 | 23 | 9.8 | 2.26 | |||||
10.1 | 26th | 21st | 15th | 3.16 | 22nd | 13 | 2.81 | 22nd | 14th | 2.96 | 20th | 16 | 3.21 | 24 | 10 | 2.45 | |||||
11 | 28 | 22nd | 17th | 3.75 | 24 | 14th | 3.34 | 24 | 15th | 3.51 | 22nd | 17th | 3.81 | 26th | 11 | 2.84 | |||||
12 | 30th | 24 | 18th | 4.46 | 27 | 15th | 3.97 | 26th | 16 | 4.18 | 24 | 19th | 4.53 | 28 | 12 | 3.26 | |||||
13 | 33 | 26th | 20th | 5.23 | 29 | 16 | 4.66 | 28 | 18th | 4.90 | 26th | 21st | 5.32 | 30th | 13 | 3.94 | |||||
13.3 | 34 | 27 | 20th | 5.48 | 29 | 17th | 4.88 | 29 | 18th | 5.13 | 26th | 21st | 5.57 | 31 | 13 | 4.19 | |||||
14th | 36 | 28 | 21st | 6.07 | 31 | 17th | 5.40 | 30th | 19th | 5.68 | 28 | 22nd | 6.17 | 33 | 14th | 4.69 | |||||
15th | 38 | 30th | 23 | 6.97 | 33 | 19th | 6.20 | 32 | 20th | 6.52 | 30th | 24 | 7.08 | 35 | 15th | 5.23 | |||||
15.4 | 39 | 31 | 23 | 7.34 | 34 | 19th | 6.54 | 33 | 21st | 6.88 | 31 | 24 | 7.46 | 36 | 15th | 5.51 | |||||
16 | 41 | 33 | 24 | 7.93 | 35 | 20th | 7.06 | 34 | 22nd | 7.42 | 32 | 25th | 8.06 | 38 | 16 | 6.09 | |||||
17th | 43 | 35 | 26th | 8.95 | 38 | 21st | 7.97 | 37 | 23 | 8.38 | 34 | 27 | 9.10 | 40 | 17th | 6.7 | |||||
18th | 46 | 37 | 27 | 10.0 | 40 | 22nd | 8.93 | 39 | 24 | 9.39 | 36 | 29 | 10.2 | 42 | 18th | 7.7 | |||||
19th | 48 | 39 | 29 | 11.2 | 42 | 24 | 9.95 | 41 | 26th | 10.5 | 38 | 30th | 11.4 | 44 | 19th | 8.3 | |||||
20th | 51 | 41 | 30th | 12.4 | 44 | 25th | 11.0 | 43 | 27 | 11.6 | 40 | 32 | 12.6 | 47 | 20th | 9.4 | |||||
21st | 53 | 43 | 32 | 13.7 | 46 | 26th | 12.2 | 45 | 28 | 12.8 | 42 | 33 | 13.9 | 49 | 21st | 10.2 | |||||
22nd | 56 | 45 | 34 | 15.0 | 49 | 27 | 13.3 | 47 | 30th | 14.0 | 44 | 35 | 15.2 | 51 | 22nd | 11.4 | |||||
23 | 58 | 47 | 35 | 16.4 | 51 | 29 | 14.6 | 50 | 31 | 15.3 | 46 | 36 | 16.6 | 53 | 23 | 12.2 | |||||
24 | 61 | 49 | 37 | 17.8 | 53 | 30th | 15.9 | 52 | 32 | 16.7 | 48 | 38 | 18.1 | 56 | 24 | 13.5 | |||||
25th | 64 | 51 | 38 | 19.4 | 55 | 31 | 17.2 | 54 | 34 | 18.1 | 50 | 40 | 19.7 | 59 | 25th | 14.8 | |||||
26th | 66 | 53 | 40 | 20.9 | 58 | 32 | 18.6 | 56 | 35 | 19.6 | 52 | 41 | 21.3 | 61 | 26th | 15.8 | |||||
27 | 69 | 55 | 41 | 22.6 | 60 | 34 | 20.1 | 58 | 36 | 21.1 | 54 | 43 | 22.9 | 63 | 27 | 17.2 | |||||
28 | 71 | 57 | 43 | 24.3 | 62 | 35 | 21.6 | 60 | 38 | 22.7 | 56 | 44 | 24.7 | 65 | 28 | 18.3 | |||||
29 | 74 | 59 | 44 | 26.0 | 64 | 36 | 23.2 | 62 | 39 | 24.4 | 58 | 46 | 26.5 | 68 | 29 | 19.8 | |||||
30th | 76 | 61 | 46 | 27.9 | 66 | 37 | 24.8 | 65 | 40 | 26.1 | 60 | 48 | 28.3 | 70 | 30th | 20.9 | |||||
32 | 81 | 65 | 49 | 31.7 | 71 | 40 | 28.2 | 69 | 43 | 29.7 | 63 | 51 | 32.2 | 74 | 32 | 23.8 | |||||
34 | 86 | 69 | 52 | 35.8 | 75 | 42 | 31.9 | 73 | 46 | 33.5 | 67 | 54 | 36.4 | 79 | 34 | 27.0 | |||||
37 | 94 | 75 | 56 | 42.4 | 82 | 46 | 37.7 | 80 | 50 | 39.7 | 73 | 59 | 43.1 | 86 | 37 | 32 | |||||
40 | 102 | 81 | 61 | 49.5 | 89 | 50 | 44.1 | 86 | 54 | 46.4 | 79 | 63 | 50.4 | 94 | 40 | 37.7 | |||||
42 | 107 | 85 | 64 | 54.6 | 93 | 52 | 48.6 | 90 | 57 | 51.1 | 83 | 67 | 55.5 | 98 | 42 | 41.5 | |||||
46 | 117 | 93 | 70 | 65.5 | 102 | 57 | 58.3 | 99 | 62 | 61.4 | 91 | 73 | 66.6 | 108 | 46 | 49.6 | |||||
52 | 132 | 106 | 79 | 83.7 | 115 | 65 | 74.5 | 112 | 70 | 78.4 | 103 | 83 | 85.1 | 121 | 52 | 63.1 | |||||
55 | 140 | 112 | 84 | 93.7 | 122 | 68 | 83.4 | 118 | 74 | 87.7 | 109 | 87 | 95.2 | 129 | 55 | 71 | |||||
60 | 152 | 122 | 91 | 111 | 133 | 75 | 99.2 | 129 | 81 | 104 | 119 | 95 | 113 | 140 | 60 | 84 | |||||
65 | 165 | 132 | 99 | 131 | 144 | 81 | 116 | 140 | 88 | 123 | 129 | 103 | 133 | 152 | 65 | 99 | |||||
70 | 178 | 142 | 107 | 152 | 155 | 87 | 135 | 151 | 94 | 142 | 139 | 111 | 154 | 164 | 70 | 115 | |||||
75 | 191 | 152 | 114 | 174 | 166 | 93 | 155 | 162 | 101 | 163 | 149 | 119 | 177 | 176 | 75 | 132 | |||||
80 | 203 | 163 | 122 | 198 | 177 | 100 | 176 | 172 | 108 | 186 | 159 | 127 | 201 | 187 | 80 | 149 | |||||
85 | 216 | 173 | 130 | 224 | 188 | 106 | 199 | 183 | 114 | 209 | 169 | 135 | 228 | 199 | 85 | 169 | |||||
90 | 229 | 183 | 137 | 251 | 199 | 112 | 223 | 194 | 121 | 235 | 179 | 143 | 255 | 210 | 90 | 190 | |||||
95 | 241 | 193 | 145 | 279 | 210 | 118 | 249 | 205 | 128 | 262 | 188 | 151 | 284 | 222 | 95 | 210 | |||||
100 | 254 | 203 | 152 | 310 | 221 | 125 | 276 | 215 | 135 | 290 | 198 | 159 | 315 | 233 | 100 | 234 | |||||
105 | 267 | 213 | 160 | 341 | 232 | 131 | 304 | 226 | 141 | 320 | 208 | 167 | 347 | 245 | 105 | 258 | |||||
110 | 279 | 224 | 168 | 375 | 244 | 137 | 334 | 237 | 148 | 351 | 218 | 175 | 381 | 256 | 110 | 282 | |||||
115 | 292 | 234 | 175 | 410 | 255 | 143 | 365 | 248 | 155 | 383 | 228 | 182 | 416 | 268 | 115 | 309 | |||||
120 | 305 | 244 | 183 | 446 | 266 | 149 | 397 | 258 | 162 | 418 | 238 | 190 | 453 | 280 | 120 | 337 |
Comparison with paper
An A4 sheet of paper (297 mm × 210 mm) is 364 mm (14.3 in) diagonal with an aspect ratio of √2 ≈ 1.414. H. between 4: 3 and 16:10. An A3 page is twice as large (420 mm × 297 mm), A5 is half the size (210 mm × 148 mm). The American letter format is similar in size to A4: 11 in × 8.5 in = 279 mm × 216 mm, diagonal 13.9 in = 353 mm.
across | high | |||||||
---|---|---|---|---|---|---|---|---|
paper | 5: 4 | 4: 3 | 8: 5 | 16: 9 | 5: 4 | 4: 3 | 8: 5 | 16: 9 |
A5 | 11 | 11 | 11 | 12 | 14th | 14th | 16 | 17th |
A4 | 15th | 15th | 16 | 17th | 19th | 20th | 22nd | 24 |
Letter | 15th | 15th | 17th | 18th | 18th | 19th | 21st | 23 |
2 letter | 22nd | 22nd | 21st | 23 | ||||
A3 | 22nd | 21st | 22nd | 24 | 27 | 28 | 32 | 37 |
A2 | 30th | 37 | 52 | |||||
A1 | 52 | 70 | ||||||
A0 | 70 | 100 |