On Being Incredibly Bright & Being LED Astray

Back in the 1970’s when I was a kid my parents eventually succumb to my pleading and bought me one of those nice 100-In-1 kits that were found at every Radio Shack. It was a blast. However, the components that held the greatest interest were those that could actually been seen to do something…especially the LEDs.

LEDs are simply amazing. They produce a bright visible light while using very little power. In the 30+ years since then LEDs have moved into all kinds of applications that were once dominated by incandescent or fluorescent light sources.

This past year we also made something of an effort to use more LED lighting in our Halloween and Christmas holiday lighting. This year LED lights are still over double the cost of the old fashioned incandescent lights. The reduced power consumption and lack of burned out bulbs makes it worth the investment. About 60% of the lights we deployed at Christmas were blue and white LEDs.

Also, this past Christmas my wife game me a Stanley LED flashlight. It’s neat in a lot of ways. Living here in hurricane alley (Houston TX) I may appreciate a good flashlight more than most people. This one has three LED elements powered by a total of six AA cells…and it’s incredibly bright! The light output capability of LEDs has grown by orders of magnitude in recent years, making them practical in more and more applications, from traffic lights to tail lights..and of course, they’re everywhere in consumer electronics.

For example, my Blackberry 9700 has an LED flash in the camera portion of the phone. It’s surprisingly effective as a photo flash. In that role a very bright LED is desirable, but that’s not always the case. As LEDs have come to dominate consumer electronics, and become evermore luminous, product designers need to take their performance into consideration.

Here’s a case in point; my wife has an employer issued Blackberry Curve 8310. It’s a decent phone. It has an LED on the upper right portion of the case that indicates the presence of messages. That LED was not well considered in the design of the phone.

To be specific, if the phone is left powered on in a dark room that one little flashing LED is aggravatingly bright. It’s so bright that unless the phone is completely covered I simply can’t sleep. It’s like living near flashing airport runway lighting. I assert that this is an overly simplistic aspect of the phones design. It’s a significant design flaw.

When you consider that every cellphone these days has a built-in camera you realize that they must also have some capability of judging exposure…and therefore some way to evaluate the brightness of their surroundings. A well considered design would use the image sensor in the phone to periodically make a determination about it’s surroundings and dim the message waiting LED to an appropriate luminosity.

In fact, why run the display backlight at full brightness when the user is in a darkened room? That’s really hard on the eyes. It should automatically vary the backlight brightness, too!

There are many cases of good design with respect to lighting in consumer products. I can recall the first time I had a chance to drive a SaabTurbo. It was a road trip from Boston to Burlington VT in an associates car. While it was a very nice car, it’s most interesting interior feature was a one-button “blackout” of all dash lighting except the tip of the speedometer. Saab obviously understood that bright lighting is not always ideal.

Looking back to the world of VoIP I’m happy that the Polycom desk phones that we use allow control of the backlight on the LCD displays. No longer does my desk glow all night long in my absence. And when I’m at my desk late at night the phone is dimmed so that I’m not blinded.

One of the most impressive things about the new Polycom VVX-1500 video phone is that it’s smart enough to turn off the LCD backlight when it makes sense to do so. It’s a green strategy since it saves power. It also saves the life of the display, and the sanity of others working nearby in a dimly lit office.

I hope that we can get the smartphone makers to give lighting control some consideration. Or maybe, just maybe, one day we’ll say, “there’s an app for that.”