Apple patent is for LED backlight for display systems
TweetFollow Us on Twitter

Apple patent is for LED backlight for display systems

An Apple patent (number 20110069511) for a LED backlight for display systems has appeared at the US Patent & Trademark Office. It relates generally to device display systems, and more particularly to an LED backlight with highly uniform color for illuminating display systems.

The patent is for a LED backlight method for display systems comprising receiving a plurality of light emitting diodes categorized into a plurality of bins, wherein each bin references a separate range of white point colors, and determining an optimal order for mounting the plurality of light emitting diodes at spatially distributed positions, the plurality of light emitting diodes comprising white point colors associated with separate bins, wherein the optimal order of the plurality of light emitting diodes produces a light of a desired white point color when the light outputs of the plurality of light emitting diodes are mixed. The inventors are Wei Chen, Jun Qi, Victor Yin and John Zhong.

Here's Apple's background and summary of the invention: "As computer technology has advanced, the demand for portable computer systems, such as laptops, has increased. Portable computers have dramatically increased the mobility of computing power for the computer user. Since the first portable computer, manufacturers have increased computer mobility by decreasing the size, weight, and power demands of portable computers, increasing battery life, and increasing performance.

"The monitors presently used contribute greatly to the overall size and weight of the portable computer. The monitor must be of a sufficient size, brightness, and clarity to provide the user with readable images. In order to achieve these requirements, monitors place a large demand on available power resources and are therefore a significant contributor indirectly as well as directly to the weight of the portable computer.

"Typically, portable computer monitors utilize a liquid crystal display system. The liquid crystal display systems typically include a top plastic or glass panel and a bottom plastic or glass panel, having a liquid crystal display of thin film transistors and liquid crystal material in between. These systems also utilize a backlight system that typically includes a diffuser for passing light evenly to the liquid crystal display, a cold cathode fluorescent lamp ('CCFL') for producing light, a reflector for directing the light toward the diffuser, and a light pipe located between the diffuser and the reflector to spread light to the entire surface of the diffuser.

"The use of conventional CCFL liquid crystal display systems in the monitors of portable computers, however, creates a limiting factor in the continuing effort to reduce the size and weight of portable computers. CCFL technology has not kept pace with advances in other technologies that have reduced the size and weight of many of the other display components. Today, one of the major limitations in further reducing the thickness and weight of the display is therefore the CCFL illumination system.

"Light-emitting diode ('LED') technology offers attractive alternatives to the CCFL. LEDs are much thinner than the CCFL and do not require many of the weighty power supply systems of the CCFL. Compared to backlights using CCFLs, backlights with LEDs have many benefits, including lighter weight, higher brightness, higher color purity, larger color gamut, longer lifetime, and mercury-free composition. However, while a single CCFL can light an entire display, multiple LEDs are needed to light comparable displays.

"A challenge with utilizing multiple LEDs, particularly when distributed in large arrays, is maintaining uniformity of color throughout the large number of LEDs. The color balance and spectra of the LEDs is governed by numerous factors such as manufacturing variances and the LED phosphorescence. For example, white LEDs are often actually blue LEDs with a complimentary yellow phosphor dot on the front of the LED. Depending upon manufacturing precision (and thus, related manufacturing costs), actual colors may therefore vary from, for example, slightly blue to slightly pink, often following a distribution curve in which many of the LEDs vary from the desired white point color. This can have a negative impact on the color uniformity of LCD displays. Understandably, reducing or compensating for such variability increases costs and complexity significantly as the number of LEDs increases in larger display configurations and environments.

"One solution is to select and utilize only those LEDs that provide the desired white point color. Such a solution, however, causes costs to be very high since only a fraction of the LED production can be utilized.

"Another solution is to compensate for LED color variations, such as by matching LEDs to one another and then filtering the light output to adjust the color to the desired white point color. This reduces the overall cost of the LEDs since most or all of the LEDs can be utilized. However, the additional color filters represent costly additional physical elements, oftentimes requiring a large number of available filter colors of finely varying shades and gradations. It can also increase the thickness of the display. An additional disadvantage is that such filters absorb light, causing the net brightness of the LED light sources to be reduced.

"Thus, if LEDs are to become a viable alternative to CCFLs, an economical and practical solution must be found to utilize a large number of non-matching LEDs while maintaining uniformity of color in the display panels in which the LEDs are utilized.

"In view of ever-increasing commercial competitive pressures, increasing consumer expectations, and diminishing opportunities for meaningful product differentiation in the marketplace, it is increasingly critical that answers be found to these problems. Moreover, the ever-increasing need to save costs, improve efficiencies, improve performance, and meet such competitive pressures adds even greater urgency to the critical necessity that answers be found to these problems.

"Solutions to these problems have been long sought but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art.

"The present invention provides an LED backlight method and apparatus for display systems. A plurality of light emitting diodes having different white point colors is provided. At least two of the light emitting diodes having different white point colors are selected to produce a light of a predetermined white point color when the light outputs of the selected light emitting diodes are mixed. The selected light emitting diodes are mounted on a display panel in a predetermined order at spatially distributed positions for mixing their light outputs to produce the light of the predetermined white point color to illuminate the display panel with the light of the predetermined white point color."

-- Dennis Sellers

 
AAPL
$101.63
Apple Inc.
-0.03
MSFT
$46.24
Microsoft Corpora
-0.46
GOOG
$573.10
Google Inc.
-2.52

MacTech Search:
Community Search:

Software Updates via MacUpdate

OS X Yosemite 10.10 DP8 - Developer Prev...
Note: This is a Developer Preview. You must be a registered Apple Mac Developer to download this update. You can also sign up for the free OS X Beta Program to download and preview public beta... Read more
FotoMagico 4.5 - Powerful slideshow crea...
FotoMagico lets you create professional slideshows from your photos and music with just a few, simple mouse clicks. It sports a very clean and intuitive yet powerful user interface. High image... Read more
Screenshot Path 1.2.1 - Change the defau...
Screenshot Path lets you change the folder where OS X saves screenshots. Screenshots are saved by default to the user’s desktop. This is handy for the occasional screenshot but those looking to take... Read more
Fantastical 1.3.16 - Create calendar eve...
Fantastical is the Mac calendar you'll actually enjoy using. Creating an event with Fantastical is quick, easy, and fun: Open Fantastical with a single click or keystroke Type in your event details... Read more
GIMP 2.8.14 - Powerful, free image editi...
GIMP is a multi-platform photo manipulation tool. GIMP is an acronym for GNU Image Manipulation Program. The GIMP is suitable for a variety of image manipulation tasks, including photo retouching,... Read more
HoudahSpot 3.9.3 - Advanced front-end fo...
HoudahSpot is an advanced file search tool built upon MacOS X Spotlight. Spotlight unleashed Create detailed queries to locate the exact file you need Narrow down searches. Zero in on files Save... Read more
djay 4.2.3 - Transform your Mac into a f...
djay transforms your Mac into a full-fledged DJ system, allowing you to mix your iTunes music library on a hyper-realistic turntable interface. Perform live, record mixes on-the-go, or enable... Read more
iDefrag 2.2.8 - Disk defragmentation and...
iDefrag helps defragment and optimize your disk for improved performance. Features include: Supports HFS and HFS+ (Mac OS Extended). Supports case sensitive and journaled filesystems. Supports... Read more
Bookends 12.2.3 - Reference management a...
Bookends is a full-featured bibliography/reference and information-management system for students and professionals. Access the power of Bookends directly from Mellel, Nisus Writer Pro, or MS Word (... Read more
Copy 1.47.0410 - Cloud storage and file...
Note: You must first sign up to use Copy (get a 5GB sign-up bonus through our 'Download' link above). Copy lets you sync, protect, and share. Everywhere. Want to bring some files home? No problem!... Read more

Latest Forum Discussions

See All

The Sleeping Prince Review
The Sleeping Prince Review By Jennifer Allen on September 15th, 2014 Our Rating: :: RESTRICTIVE KINGDOM SAVINGUniversal App - Designed for iPhone and iPad The Sleeping Prince looks and feels great to play, but its lack of peril and... | Read more »
It Came From Canada: Terra Battle
In some way or another, most Japanese RPGs owe something to Final Fantasy. But with Terra Battle, the now-common mix of Western medieval fantasy with Eastern anime aesthetic feels earned. After all, its developer, Mistwalker, was founded by the... | Read more »
Five Nights at Freddy’s Review
Five Nights at Freddy’s Review By Rob Thomas on September 15th, 2014 Our Rating: :: FIVE FRIGHTS AT FREDDY'SUniversal App - Designed for iPhone and iPad Can you survive five nights as the new night watchman of Freddy Fazbear’s... | Read more »
Phantom Rift Review
Phantom Rift Review By Nadia Oxford on September 15th, 2014 Our Rating: :: FRIENDLY PHANTOMUniversal App - Designed for iPhone and iPad Despite a snag here and there, Phantom Rift is a well-crafted and imaginative adventure RPG.   | Read more »
Phantom Rift – Tips, Tricks, Strategies,...
Hello, Wanderers: | Read more »
Meet the Newest Character for Temple Run...
Meet the Newest Character for Temple Run 2, from National Geographic Kids’ Action-Adventure Book Posted by Jessica Fisher on September 15th, 2014 [ | Read more »
Battle Riders Review
Battle Riders Review By Jordan Minor on September 15th, 2014 Our Rating: :: UNTWISTED METALUniversal App - Designed for iPhone and iPad BattleRiders has cool car combat, but it could be crazier.   | Read more »
Rapture - World Conquest (Games)
Rapture - World Conquest 1.0.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0.0 (iTunes) Description: The End is coming! Bombard the globe with devastating miracles and decimate the enemy civilizations. Guide your... | Read more »
Toonia Jelly: Music Review
Toonia Jelly: Music Review By Amy Solomon on September 15th, 2014 Our Rating: :: CUTE MUSICAL EXPLORATIONUniversal App - Designed for iPhone and iPad Toonia Jelly: Music is a charming exploratory app for young children with a... | Read more »
CounterSpy Review
CounterSpy Review By Lee Hamlet on September 15th, 2014 Our Rating: :: AN EXCELLENT PORTUniversal App - Designed for iPhone and iPad Shaken or stirred, CounterSpy is simply the best stealth action game to sneak its way onto the App... | Read more »

Price Scanner via MacPrices.net

10% off iPhone 6 and 6 Plus Otterbox cases
Get 10% off on popular Otterbox iPhone 6 and iPhone 6 Plus cases at MacMall through September 19th. Use code OTTERBOX10 to see the discount. Read more
15-inch MacBook Pros on sale for up to $125 o...
Amazon has the new 2014 15″ Retina MacBook Pros on sale for up to $125 off MSRP including free shipping: - 15″ 2.2GHz Retina MacBook Pro: $1899.99 save $100 - 15″ 2.5GHz Retina MacBook Pro: $2374... Read more
27-inch 3.2GHz iMac on sale for $1698, $101 o...
Abt has the 27″ 3.2GHz iMac on sale for $1698 including free shipping. Their price is $101 off MSRP. Read more
More To Making A Larger iPad Than Expanded Sc...
CNET’s Ross Rubin has posted a thoughtful analysis of prospects for a larger display iPad Pro, noting that Microsoft and Samsung currently have the large-display touchscreen tablet category to... Read more
SwiftKey Keyboard Finally Coming To iPhone An...
At the TechCrunch Disrupt event in San Francisco, Swiftkey unveiled the first details about SwiftKey Keyboard for iPhone, iPad & iPod touch. SwiftKey’s philosophy is that you should be able to... Read more
Save $75 on the 16GB iPad mini with Retina Di...
Best Buy has the 16GB iPad mini with Retina Display on sale for $324.99 on their online store for a limited time. Their price is $75 off MSRP, and it’s the lowest price available for this mini.... Read more
21-inch 1.4GHz iMac on sale for $979, $120 of...
B&H Photo has the new 21″ 1.4GHz iMac on sale for $979.99 including free shipping plus NY sales tax only. Their price is $120 off MSRP. B&H will also include free copies of Parallels Desktop... Read more
Apple restocks refurbished 21-inch 1.4GHz iMa...
The Apple Store has restocked Apple Certified Refurbished 21″ 1.4GHz iMacs for $929 including free shipping plus Apple’s standard one-year warranty. Their price is $170 off the cost of new models,... Read more
13-inch 2.6GHz/256GB Retina MacBook Pro on sa...
Adorama has the 13″ 2.6GHz/256GB Retina MacBook Pro on sale for $1379 including free shipping plus NY & NJ sales tax only. Their price is $120 off MSRP, and it’s the lowest price available for... Read more
Macally iPhone 6 Cases
Macally has introduced a Line of Snap-On Shell Cases, Frame Bumper Cases and a Rugged Protective Case for iPhone 6 with 4.7inch Screen, such as the SNAP case in a variety of brilliant metallic... Read more

Jobs Board

*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.