This was our experience too. When we started to measure the width and height of the screens in the store (in millimetres), it soon seemed obvious to us that the screens had been designed and built using millimetres.
Cheers, Pat Naughtin Geelong, Australia On 2011/05/15, at 11:30 , Kilopascal wrote: > Interesting thing about screen sizes. I recently bought a small "10.1 inch" > LCD TV from Haier. If you measure the screen width x height is is exactly > 220 mm x 130 mm. Using Pythagoras's theorem, the diagonal is 255.553 mm. > Dividing this by 25.4 gives you 10.061 inches. I can see where they rounded > up that number to 10.1 to sell it. > > Even though neither the millimetre nor inch are rounded numbers, it seems > that the width x height dimension is a rounded amount in millimetres. I was > in the store this afternoon and noticed some of the "47 inch" sets showed in > small print their diagonal as 46.96 inches. I converted this to millimetres > when I got home and got another senseless number 1192.784 mm. I now wonder > if I would have measured the width x height would I get a set of rounded > metric numbers. > > I worked the diagonal backwards and sure enough I got a round number of 1000 > mm x 650 mm. I was able to do this by replacing the height in Pythagoras's > theorem with (9/16)W. I then solved for the width and got a number slightly > over 1000 mm and then calculated for the height and got 649.5xx mm. I then > assumed that the true size must be 1000 x 650. To prove it is so, I took > 1000^2 + 650^2 and got 1 422 500. I took the square root and got 1192.686 > mm, which was close to what I calculated from converting the inches to > millimetres. Now when I convert 1192.686 mm to inches I get 46.956 inches > and when rounded, it becomes 46.96 inches as is noted in the small print on > the store sign. > > You can calculate the width of any TV by the formula: W^2 = 256/337 (D^2); > H^2 = D^2 - W^2 > > A "40 inch" (39.9 inch diagonal viewable) has a diagonal dimension of 1013.46 > mm. This means the width is 880 mm and the height is 500 mm. Working this > backwards gives you a diagonal of 39.847 inches, rounded to 39.9 inches (even > though improperly). > > I'm sure this can be tried for all advertized sizes. What it also means is > that in order for advertisers to sell TVs and monitors using metric > dimensions, then they need to state the width x height dimensions and not the > diagonal. If the lawsuit forces the companies to show the inches to 2 or > more decimals, then it will make it easier for us to discover the true, > rounded metric size. > > > [USMA:50467] Screen sizes in Australia > > Pat Naughtin > Sat, 14 May 2011 00:31:14 -0700 > > You might be interested in a draft letter that I am about to send to a > television retailer. Here is part of the letter; the rest is about their > image > in the community. > > Dear Television Retailer, > > Recently, my wife and I went to buy a new television set. We had in mind a > particular type of television and it had to be the right size to fit the > space > we had. As my eyesight is decreasing, I was also interested in the true size > of > the screen. > > As we browsed, a salesman approached us. I asked if he could tell me the size > of the television screens that were on display. He began to tell me some > numbers using the word, inch. > > I interrupted to ask if could he tell me the width and height of the screen > in > millimetres as this would give me not only the size of the screen but also > the > aspect ratio. I also tried to explain that I did not understand his use of > the > word inch, as I had not personally used this word for any measurement since > the > 1960s. > > I didn’t get far. The salesman went into an angry dissertation about the > word, > inch. No — to say "an angry dissertation" is too kind — the salesman was > incandescent with rage because I had asked for the width and height of the > screen in millimetres. > > To put my request into context it might be useful for you to know: > > 1 I am recognised as a world leader in metrication, the process that > people use to upgrade from all of the millions of old pre-metric measuring > words to modern metric system units. My clients include NASA, NIST, Google, > and > the Metric Associations of Canada, the UK, and the USA. The United States > Metric Association (USMA) recognises me as a Lifetime Certified Advanced > Metrication Specialist. I have also been approached for specific metrication > advice by the governments of Australia, Ethiopia, Saint Lucia, the UK, and > the > USA. > > 2 I have been aware of the strange use of the word inch or " for > television > screens since just before the Melbourne Olympic Games in 1956 when, as a > small > boy, I helped my mother buy our first television set. At that time I learned > that the strategy of television manufacturers and marketers was to specify > the > full wraparound of something called phosphor diagonally as the size of the > screen. It was obvious to me that the sales staff were routinely lying to us > so > I took to carrying a tape measure with us when my mother and I went > television > shopping and I physically measured the diagonal of the screen that we could > actually see. Eventually my mother bought a 21" television that I knew was a > diagonally measured nineteen inch screen. With hindsight, I wonder whether > this > was really designed and made as a 500 millimetre screen that was 400 > millimetres wide and 300 millimetres high — giving it an aspect ratio of 4:3. > > 3 I am also aware that in 2010 seven California counties and the > California > Division of Measurement Standards sued Sony, Panasonic, LG, Sharp, and > Samsung > over their inch based rounding* practices arguing that the devious behaviour > of > these companies was incompatible with consumer protection laws. As I recall > the > television manufacturers and marketers settled at the end of December 2010, > agreeing to distribute $1 125 000 worth of televisions to schools and other > public institutions throughout California and to pay court costs of $1 250 > 000. > (* Rounding from a screen that was designed and built using millimetres!) > > At this point, my wife and I left the shop, more bemused than angry, went > home > to pick up a millimetres only tape measure, and then went to another shop > where > we measured and bought a new television for about $1000 that suited our needs > and the space we had available. > > However, to be kind to you, I suppose that your strange behaviour might > simply > be a misunderstanding of the history of the metrication process. > > You may recall that the television manufacturers and the television retailers > met with representatives of the Australian Metric Board in the mid-1970s. I > know that at this meeting the manufacturing and retailing industry > representatives and the board members reached a unanimous consensus agreement > that in future all television and all computer screens in Australia would be > specified in centimetres. I know this because I have been able to discuss > this > meeting with a person who was present at the meeting. > > As you know this centimetre based decision did not work. The television > manufacturers and the television retailers soon reneged on their agreement > and > reverted to specifying screen sizes using inch or ". > > The unfortunate part of this saga is that the television manufacturers, the > television retailers, and the representatives of the Metric Board were > unaware > of the cause of the failure. Following extensive research, I believe that the > reason is quite simple: > > Metrication transitions have never been successful using centimetres. > > For a successful metrication transition centimetres have never worked. If you > choose to use centimetres for a metric system transition you should allow at > least 200 years for the change to take place. Consider some examples: > > 1 Clothing sizes were changed to centimetres from the 1790s — we still > use > size numbers and inches for this purpose. > > 2 Many attempts have been made to measure and fit shoes in centimetres > since the early 1800s — we still use arbitrary size numbers for shoe sizes. > > 3 Many legal and medical authorities have tried to make us use > centimetres > for human height — many, perhaps most of us, still use feet, inches, and > fractions of inches for our height. > > 4 The Kodak Company accidentally did a controlled experiment when they > upgraded to the metric system in 1910. The film division chose millimetres > for > the transition and their upgrade was completed by 1912. The photographic > paper > division chose centimetres and they are still struggling with the change more > than 100 years later; in 2011 you can routinely buy Kodak photographic papers > specified in inches. > > 5 The medical community in the USA is still trying to change to the > metric > system using centimetres. There are so many measurement related medical > errors > in the hospitals of the USA that unnecessary deaths could be estimated at > about > 60 000 additional deaths per year. Go to > http://www.aarp.org/health/doctors-hospitals/info-10-2010/preventable-medical-mistakes.html > and http://books.nap.edu/openbook.php?record_id=9728&page=1 for details. > > 6 Software companies, such as Apple and Microsoft, have tried to use > centimetres for word processing ever since word processors were invented. > They > have consistently failed. Apple is still trying to divide centimetres into > halves and quarters while Microsoft continues to set default page margins in > inches and quarter inches. The cost to word processor users is incredible: > see > http://www.metricationmatters.com/docs/PageBordersInchesORmillimetres.pdf > > 7 The USA, as a nation, has tried to upgrade to the metric system since > the > 1790s — more than 200 years ago — using centimetres. They have failed so > dismally that their multi-faceted measuring methods now cost the USA roughly > 1.3 trillion dollars a year. To repeat a reference, see > http://www.metricationmatters.com/docs/CostOfNonMetrication.pdf > > And we can also add: > > 8 The attempt to upgrade the measurement of television and computer > screens > to simple and rational metric system sizes using centimetres did not work. > > Cheers, > > Pat Naughtin LCAMS > Author of the ebook, Metrication Leaders Guide, see > http://metricationmatters.com/MetricationLeadersGuideInfo.html > Hear Pat speak at: http://www.youtube.com/watch?v=_lshRAPvPZY > PO Box 305 Belmont 3216, > Geelong, Australia > Phone: 61 3 5241 2008 > > Metric system consultant, writer, and speaker, Pat Naughtin, has helped > thousands of people and hundreds of companies upgrade to the modern metric > system smoothly, quickly, and so economically that they now save thousands > each > year when buying, processing, or selling for their businesses. Pat provides > services and resources for many different trades, crafts, and professions for > commercial, industrial and government metrication leaders in Asia, Europe, > and > in the USA. Pat's clients include the Australian Government, Google, NASA, > NIST, and the metric associations of Canada, the UK, and the USA. See > http://www.metricationmatters.com for more metrication information, contact > Pat > at [email protected] or to get the free 'Metrication > matters' > newsletter go to: http://www.metricationmatters.com/newsletter to subscribe. > > Pat Naughtin LCAMS Author of the ebook, Metrication Leaders Guide, see http://metricationmatters.com/MetricationLeadersGuideInfo.html Hear Pat speak at: http://www.youtube.com/watch?v=_lshRAPvPZY PO Box 305 Belmont 3216, Geelong, Australia Phone: 61 3 5241 2008 Metric system consultant, writer, and speaker, Pat Naughtin, has helped thousands of people and hundreds of companies upgrade to the modern metric system smoothly, quickly, and so economically that they now save thousands each year when buying, processing, or selling for their businesses. Pat provides services and resources for many different trades, crafts, and professions for commercial, industrial and government metrication leaders in Asia, Europe, and in the USA. Pat's clients include the Australian Government, Google, NASA, NIST, and the metric associations of Canada, the UK, and the USA. See http://www.metricationmatters.com for more metrication information, contact Pat at [email protected] or to get the free 'Metrication matters' newsletter go to: http://www.metricationmatters.com/newsletter to subscribe.
