At the 2008 Consumer Electronics Show ( CES ) in Las Vegas , Nev. convention - goers ogledconcept carsshowing off the latest in car stereo engineering , onboard gadgetry and comfort . Among them was a K - smutty BMW X5 deliver by Visteon and 3M.
The black BMW at CES was Visteon and 3 M ’s promotional prototype showing off what the two company can do when they put their foreland together . The BMW hold 50 new engineering , everything from space sensors in the rear bumper to an eye - view 3 - five hundred dashboard exhibit .
But perhaps one of the coolest – if not exactly the flashiest –features was the use of something calledtransmissive filmto vastly improve the pellucidity and brightness ofLCDdisplays on the dashboard . Transmissive film get its name fromtransmissive LCDscreens , which use a backlight to illuminate the individual on - concealment pixels . Transmissive LCD projection screen are vulgar oncomputer monitor , high-pitched - destruction LCD televisions , PDAs , cell phonesand even some digital watch .
3 M is a pioneer in transmissive film , design impossibly sparse sheets of polymer – down to 62 µm in thickness ( that ’s 62 millionths of a meter ) – that can be applied outdoors or inside an LCD screen door to greatly improve brightness , clarity and direction control of the image .
A typical LCD exhibit lose a mint of luminousness between the backlight and the image that appears on the screen . 3 G estimates that only 8 to 10 pct of the backlight is actually seen by the viewer [ source:3 M ] . The rest is lost as the light egest through various polarizers , colour filters and theliquid crystalof the LCD panel . By using various transmissive films , LCD manufacturers can airt , recycle and inflate light to increase get-up-and-go efficiency by as much as 120 pct [ source:3 M ] .
Another issue with LCD screens is security . If you ’re support at an automated Edward Teller motorcar , you do n’t want everyone around you to make out how much cash is in your checking report . Or if you ’re working on your novel at the local Starbucks , you do n’t require the guy at the next table getting a sneak trailer . Transmissive films can serve deflect LCD images from anyone not support straight in front of the screen .
So how precisely do transmissive films work within an LCD equipment ? For that matter , how to LCD devices work ? Keep reading for an intromission to LCD technology and how different variety of transmissive films can make the LCD experience more efficient and user well-disposed .
LCD Basics
The acronymLCDis little forliquid crystal display . limpid quartz refers to a special chemical chemical compound that lies at the centre of this groundbreaking technology . But we ’ll get to that in a mo .
First , let ’s babble out about digital images . Every digital image – LCD displays included – is compose of millions of individualpixels , the name for smallest visible unit of the image . On a color LCD display , each pixel is ruin down into three subpixels . These subpixels are each assign a people of colour : reddened , gloomy or green . The dissimilar colors that you see on an LCD show are produced by controlling the intensity of the light available to each ruby , unripe and blue-blooded subpixel .
This is where it gets interesting . The fashion LCD video display control how much light is available to each red , green and blue subpixel is through teeny - tiny particles calledtwisted nematic form liquidness crystals . perverted nematics get their name because they are wind in their natural state . But when you lend oneself an electronic charge to a twisted nematic crystal , it untwists .
What researchers figured out is that they could apply different charges to the distorted nematics to get them to untwist only partially . In an LCD showing , each crimson , greenish and low subpixel has its own twisted swimming crystal . If the fluent crystal associated with the red pixel is untwisted all the way , but the blue and immature crystals remain unopen , then the pel will show a utter violent vividness . Untwist the low-spirited crystal , and the picture element will now be purple . Untwist all three to varying grade , and you could make every imaginable coloring material in the spectrum .
Most high - end LCD screens are call transmissive because the light source comes from behind the screen . That visible light is generate by a small fluorescent tube attached to perch guidethat directs the light forward toward the LCD board .
When the light reaches the LCD panel , it must first authorise through apolarizerthat aligns the igniter with the rows of twisted liquid crystals . By charging the crystals , light is only allowed to pass through certain subpixels , setting the color of each of the millions of pixels connect with the digital image .
For more details about the technology behind LCD displays , say our clause onHow LCDs Work .
So where do transmissive films set in to all of this ? Transmissive films can be applied to the backlight field of the LCD system or the LCD showing concealment itself to greatly increase the uncloudedness , brightness , security and energy efficiency of the system . Read on to find out more about the dissimilar types of transmissive films .
Types of Transmissive Film
3 M excogitation and manufactures several different types of transmissive films that can be used alone or combined together within the same merchandise to enhance the performance of theLCDdisplay .
Let ’s verbalise about brightness first . 3 M utilize two different kinds ofbrightness enhancement filmsfor the LCD displays in the BMW concept motorcar . The first is a single sheet of polymer imprint with a prismatic open pattern . The pattern looks like the teeth of a gear or a series of triangles point out from the flat film aerofoil .
The prism on the brightness sweetening film airt light from the backlight toward the watcher . Without these prisms , a slew of the Inner Light from the backlight would be wasted – shine too high or too low for the viewer to see . Think of a non - LCDtelevisionset whose luminosity reflects off the ceiling and floor . With brightness enhancement film , all of the light is aim straight out toward the viewer , with any supererogatory Christ Within reabsorbed by the back panel of the display .
The second transmissive film used to increase brightness is calleddual brightness enhancement film . Its name fare from the fact that the film is not only mounted with prisms , but with an extra pondering sheet for recycling any luminance that does n’t hit the optical prism at the correct angle . In this configuration , light go forward to bounce around the back of the LCD video display until it happen upon the luminousness sweetening film at the optimum angle to be directed out toward the witness .
Antireflectiontransmissive film can be applied to the surface of an LCD display to reduce brilliance and increase clarity . 3 M ’s antireflective flick is actually several layers of cinema in one . The top stratum is an antifingerprint picture that makes it easy to wipe fingerprints fromPDAor computer screens . The second bed is antiglare film , which think over spark at multiple angles , diffusing the glare effect . A third level protects PDA projection screen from scratch . And a 4th layer is a nontacky adhesive that allows the film to be easily removed and replaced in case of scratches or other damage [ source : 3 M ] .
For privacy and protection issues , 3 M has developedlight control filmsthat usemicrolouversto stop screen images from anyone who is n’t forthwith in front of the LCD display . Microlouvers are like microscopic Venetian blinds that luff direct out toward the viewer . Anyone to the left or the right of the screenland will only see black . 3 M sell a special product forlaptopand other LCD computing gadget monitors called a Privacy Filter . The privacy filter is essentially a light control film that can be adhere straightaway to a computer concealment .
Another type of transmissive film calledenhanced specular reflecting telescope filmcan be use behind the backlight to maximize the statistical distribution of lightness from of a single light source . The enhanced mirrorlike reflector film is actually made up of one C of microscopically lean polymer layers of alternating high and low frequency reflecting telescope . The result is a reflection rate of more than 98 percent , nifty than the normal flatware mirror you have in your lav [ source:3 M ] .
For more information about LEDs , LCDs and related technologies , shift your eyes to the links on the next page .
God bless the good mass at 3M. If it were up to me to come up with the next technical innovation , we ’d all still be break off away at animal skins with sharpened Flint River . But somehow researcher at ship’s company like 3 M figure out how to cook up a shroud of polymer that is 62 millionths of a m in thickness . Not only that , but the impossibly sparse polymer is implant with strategically design reflectors and refractors and prisms that actually serve well a utilitarian purpose . Next time you marvel at the clarity and light of your iPad screen , give a silent shout out to these guy rope .
