Shedding Light on Pixel Sharing

The facts behind the figures

35mm, 20mm, 16mm – every manufacturer of LED digital color displays loves to pitch their “pitch” when it comes to their products, and the race is on as to who can be the next to offer the smallest number. Strictly speaking, pitch is the distance between the clusters of red, green, and blue LEDs that make up a single pixel in a sign. The tighter the pitch (i.e., the smaller the number), the greater the resolution and image quality in a board. But the “pitch” that some companies offer actually utilizes a technique called pixel sharing to achieve the pitch in a “virtual” manner. Before you buy your LED display product, you should first understand more about pixel sharing and determine if this approach will work for your application.

Figure 1 Physical pixels

Figure 2 “Shared Pixels” (circled in yellow)

Figure 3 Boards that use shared pixel technology also switch between lines of LEDs, generating additional rows of virtual pixels as shown in blue.

Virtual Reality

Figure 1 diagram is a common 32mm pixel arrangement that may be represented as a tighter 16mm “virtual” pitch, which is achieved through running software that shares the LEDs in different pixel combination. Figure 2 and 3 show how the LEDs become “shared”, creating new virtual pixels. When the sign is powered on and generates images, these rows of LED pixels fire in staggered rows alternately. The human eye then interpolates this visual data into perceived color.

Table 1 compares the pixel density for this “virtual” 16mm board with a real 20mm board. Although the “virtual” 16 mm board has 22% fewer LEDs, it seems to deliver higher resolution. The initial impression that these figures seem to show is that this type of board can effect a 16mm resolution with 22% fewer LEDs. At first glance, this seems like great news! From the manufacturer’s point of view, this new product has 22% fewer LEDs compared to a true 20mm product and 50% fewer LEDs than a true 16mm product. This means that the product will cost about 50% less to manufacture than a true 16mm product, or 22% less than a true 20mm product. From the end user’s point of view, getting a higher resolution at a lower cost is a simply a terrific bargain.

But is this really the case?

Table 1: LEDs per square foot

Weighing Your Choices

First, consider the overall brightness. How can a product with half the LEDs be as bright as one with twice as many? The answer is that it can only be brighter if the LEDs are driven harder or kept on longer. Over-driving LEDs dramatically reduces product life and quickly deteriorates the color and brightness.

Second, if I have a static picture, how can I have a LED that is shared in 4 pixels operate correctly, or at 4 discrete levels? The answer is you can only if you multiplex this pixel, or share the “on time” of a pixel with its neighbors. Multiplexing further reduces the light available for each of the specific pixels. So, once more, to achieve a bright image, you will have to resort to overdriving the LEDs again.

So are there any cases where pixel sharing makes sense? The answer is “yes” of course. If your display is running video , you can get a better picture at a lower cost and a lower weight, but at the cost of a decrease in the overall life of the product. Perhaps you have a video replay board that is only operating for a few hours on a weekend. Maybe brightness isn’t an issue for you. You might want a big sign but are concerned about overall weight. Or you have an extremely tight budget, and think you can live with the drawbacks. Any of these situations might make a strong case for pixel sharing. It’s certainly a decision that seems confusing and contradictory on many levels.

However, for the end user who wants to make the most economical choice without sacrificing performance, there are alternatives. If the people viewing the board are more than 200′ away, you might consider going to a 20mm or 23mm pitch. Since they contain fewer LEDs than a true 16mm, these displays are cheaper per square foot, lighter, and brighter, and actually yield better static image quality than a 32mm product that utilizes pixel sharing.

Making the Decision

Pixel sharing does save on power and weight, but the price you pay is a decrease in content resolution, image crispness, and product longevity. The virtual pixel must share LEDs from its neighbors, flashing at a high frequency so the eye cannot pick up on it. This works effectively for moving video images, but lends an annoying flicker to static images.

You might ask, “How can I protect myself when considering a product with pixel sharing?” Firstly, you should run your own content, not the content the manufacturer might suggest. Run this content in an environment that your sign will be in once installed (in direct sunlight, south facing, for example). If the sign looks good in this installation, then this might be a viable choice for your purposes. Most importantly, ask for a warranty that guarantees at least 5 years of an
image quality that has not deteriorated.

With advances in LED technology in recent years, such as the incorporation of lighter materials and more efficient electronics, products offering “real” 16mm and smaller pitches are beginning to come on the market at lower prices than ever before. As end users become more sophisticated as to the ins and outs of the new generation of LED displays, the “virtual pixel” may well be on its way out. However, the well-informed consumer owes himself -and his business – a basic understanding of the many meanings behind the concept of “pitch”.

The Pitfalls of Pixel Sharing?

• Reduced product life

• Color deterioration

• Poor static image quality

• Flickering images

• Quick obsolescence

Courtesy of Adaptive

At Manufacturers Automation, we are dedicated to customer service and want to make your experience with Adaptive a pleasant one.

Consult the Small Business Administration weblink when considering purchasing an electronic message center.

http://www.sba.gov/smallbusinessplanner/start/pickalocation/signage/text/emcfaq.html

WHY ELECTRONIC MESSAGE CENTERS?

Grow your business? In this economy?

Right now, growth is probably the last thing on your mind. Survival is the new business strategy. But rather than cut back and trim down, why not take this as an opportunity to re-prioritize –especially when it comes to your advertising budget?

Traditional media like print and broadcast are shrinking in influence, and rising in cost. Instead of paying over and over for an ad that might or might not be noticed or heard, you may want to consider the power of electronic message centers — an on-premise advertising solution that you pay for once, but lasts for years!

According to a study by the Small Business Administration, EMCs have been reported to generate a 15% to 150% increase in sales.

What does this really mean? Consider a modest business that might bring in 1,000 per day in revenue. Add in the minimal 15% increase in sales that an EMC has been shown to deliver, imagine the results: an extra $150 per day, $1,050 a week, $54,600 a year. What other investment can you think of that covers its cost in just one year?

Instant Marketing

Versatility is what gives EMCs the winning edge. Adaptive’s intuitive Ooh!Media software makes it easy for you to quickly change your message to capitalize on sudden opportunities (“Snow is on the Way – Gas up Now!”), or schedule promotions around times of the day or holidays.

No more waiting for the next paper to come out, or for a banner to come back from the printer: this is instantaneous communication!

Reach today’s on-the-go buyer!

Do you know how many people drive by your business every day? If you’re on a major street or visible from the highway, that could be tens of thousands, and every one is a potential customer.

Adaptive is the answer

When it comes to electronic message centers, Adaptive knows the technology like no one else. Our business is to get people into your business, and for over 30 years, that’s been our focus.

© 2009 Adaptive Micro Systems Printed in the U.S.A. 3/09 Form No. 9700-2011

At Manufacturers Automation Inc., we are dedicated to customer service and want to make your experience with Adaptive led displays a pleasant one.

Consult the Small Business Administration weblink when considering purchasing an electronic message center.

http://www.sba.gov/smallbusinessplanner/start/pickalocation/signage/text/emcfaq.html

Adaptive LED Displays are among the best on the planet today and would like more detailed information on LED Displays.

There are a couple of ways to have more information and I would suggest if you are interested in LED Displays that you either contact us for details or take a look at the below information in PDF format.

Top Distributor Awards for 2008

Hello Everyone:

Just a short note to show appreciation to our clients for helping us win top distributor awards for Moxa Industrial Networking Products and Adaptive LED Displays.

As a distributor of high quality LED Signs and Industrial Networking products we are proud to announce that we have received two coveted awards from top manufacturers.

Moxa Top Distributor Award for 2008 which we have won two years in a row.

Adaptive LED Displays we have been Awarded Top Distributor for 2008 and have won this award for three years in a row.

We appreciate our clients who have helped us achieve this great honor and are looking forward to servicing you in the coming years.

Sincerely,

Brent Raynor

by Brent Raynor www.manuauto.com

Alphamation is a library of creative graphics for business, and holiday events. It will enhance your presentation and get more results. The graphics are designed to work with your Adaptive AlphaEclipse, StreetSmart and Excite led displays.

• http://www.manuauto.com/pdf/customalphamationsheet.pdf (Alphamation Brochure)
• http://www.manuauto.com/support/adaptive/adaptive-software-downloads/ (#2 Alphamation V4)

At Manufacturers Automation Inc., we are dedicated to customer service and want to make your experience with Adaptive led displays, a pleasant one.

© Copyright 2007, Manufacturers Automation Inc., www.manuauto.com

(Using Jasc Animation Shop)

by Geoff Small www.manuauto.com

• Open the GIF

• Go to Effects, then Insert Image Transistion
• Click on Animation Frame
• Transistion length 2.0 seconds
• Frames per second: 10
• Effects is Spin
• Click on Show Preview and click ok.

• Go to Animation and Reverse Frames.
• Move the slider bar to the left side and delete the blank frames. Save as a new GIF and click next until the graphic optimization finishes.

• Open the original GIF.
• Go to Effect, then Insert Image Transistion, click ok.
• Move the sliderbar to the right and delete the empty boxes.
• Go to Edit and Paste.
• Select After Current Fame
• Delete the empty boxes.
• Run the simulator to verify (should be 22 frames) and save as a GIF.

At Manufacturers Automation Inc., we are dedicated to customer service and want to make your experience with Adaptive led displays, a pleasant one.

© Copyright 2007, Manufacturers Automation Inc., www.manuauto.com