Next-gen MacBook Pro to shine brighter with new backlight tech

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  • Reply 41 of 101
    gsxrboygsxrboy Posts: 565member
    I have always thought that the 15" powerbook/mbp was Apples flagship product. I am looking forward to updating sometime this year. LED backlit higher res screen, leopard, res independence, santa rosa and penryn maybe even ! that will be an awful nice mbp
  • Reply 42 of 101
    Quote:
    Originally Posted by wtfk View Post


    Weren't the allegations largely shown to be BS?



    Doesn't stop the company being infamous; false allegations can be just as damaging to a reputation as truthful ones.
  • Reply 43 of 101
    Quote:
    Originally Posted by CoolHandPete View Post


    In the "white paper" linked in the article, supposedly the current (2nd gen) LEDs are 12 percent more efficient than CCFL - with higher efficiency expected soon. Even though the battery life may not be so much longer than current models, the brightness improvement should make the switch worthwhile.



    Do you think the price point will remain the same?



    It should be fairly close. With LED, there's no need for a high voltage inverter, which cuts the cost a little. CCFLs aren't really that cheap either, it's just that until now, there hasn't been a good way to get white LED backlights to have uniform brightness without building a relatively thick diffuser panel behind the LCD.



    It's also worth noting that most LEDs have a "sweet spot" brightness level where roughly 30-50% of the max recommended bias current produces 80% of the max brightness. So you'll save a lot of power if the brightness is turned down just a little.
  • Reply 44 of 101
    Quote:
    Originally Posted by melgross View Post


    LED's dim as well, but their lifetime is so much longer, that it might not be noticable during the laptops lifetime.



    A camera would have to work through the backlight, LCD, and color filters. With any current tech, it's not possible. I can think of some future tech that might, but it's too speculative.



    LEDs are actually quite versatile and are easy to dim. I am remodeling my house right now and am putting in LEDs wherever possible. Even with a 75% efficient AC-DC converter, the LEDs are much more energy efficient than incandescents and halogens. They can be dimmed by reducing the current across the diode (the D in LED), which is essentially the same as lowering the voltage over the bias resistor. But in practice they can also be dimmed by PWM, which is really simple to implement and is more energy efficient than using a variable input voltage (won't get into why, but just accept it. . .)



    Right now I'm working on customizing some off-the-shelf lutron dimmers to handle the task of LED dimming for interior lighting.
  • Reply 45 of 101
    jeffdmjeffdm Posts: 12,946member
    Quote:
    Originally Posted by Splinemodel View Post


    But in practice they can also be dimmed by PWM, which is really simple to implement and is more energy efficient than using a variable input voltage (won't get into why, but just accept it. . .)



    I'll back you up on this. Efficiency varies with power input. You can pulse the light at its optimum efficiency point, and change the pulse width to vary its brightness. It's easier to dim them linearly with PWM because LEDs are not power-linear devices but you can linearly change the pulse width. Retinal physiology also shows that very fast pulsing lights makes them "seem" nearly as bright even if they are on 50% of the time. One might not notice the pulsing, but nearly every LED I've seen in a device is pulsed. I think there are other reasons too.
  • Reply 46 of 101
    jeffdmjeffdm Posts: 12,946member
    Quote:
    Originally Posted by Kzelk4 View Post


    So with a brighter screen and resolution independence on Leopard, is it likely Apple will come out with a HD laptop screen ( or a higher resolution), or am I way off? Don't know much about screens



    It can be done but Apple choses not to. I can understand why, because it makes everything so tiny on the screen. I also think that the people that want such high pitch screens on a notebook are a minority.
  • Reply 47 of 101
    jeffdmjeffdm Posts: 12,946member
    Quote:
    Originally Posted by melgross View Post


    The lifetime of an LED is determined by the time it takes for the light output to drop by 50%, for most uses. For more critical uses, 25% is the standard rating.



    Aren't fluorescents also rated by a half-life?
  • Reply 48 of 101
    chuckerchucker Posts: 5,089member
    Quote:
    Originally Posted by JeffDM View Post


    It can be done but Apple choses not to. I can understand why, because it makes everything so tiny on the screen. I also think that the people that want such high pitch screens on a notebook are a minority.



    Hm? "Making everything so tiny on the screen" is precisely what resolution independence changes, which is what Kzelk4 was referring to.



    The way Steve stressed the high resolution on the iPhone several times during the keynote, I think it's becoming increasingly likely that, once Leopard is out, Apple will start rolling out screens with higher ppi.
  • Reply 49 of 101
    boogabooga Posts: 1,077member
    Quote:
    Originally Posted by Splinemodel View Post


    LEDs are actually quite versatile and are easy to dim. I am remodeling my house right now and am putting in LEDs wherever possible. Even with a 75% efficient AC-DC converter, the LEDs are much more energy efficient than incandescents and halogens. They can be dimmed by reducing the current across the diode (the D in LED), which is essentially the same as lowering the voltage over the bias resistor. But in practice they can also be dimmed by PWM, which is really simple to implement and is more energy efficient than using a variable input voltage (won't get into why, but just accept it. . .)



    Right now I'm working on customizing some off-the-shelf lutron dimmers to handle the task of LED dimming for interior lighting.



    I'd just like to say that dimming LEDs by blinking them fast should be banned! It gives me a headache, and when I'm behind a new Cadillac is extremely distracting as my eye moves across the field of vision. I think I'd have seizures (not really, but I'd feel like having one) if I walked into a house where the LEDs dimmed by blinking.
  • Reply 50 of 101
    melgrossmelgross Posts: 31,789member
    Quote:
    Originally Posted by Splinemodel View Post


    LEDs are actually quite versatile and are easy to dim. I am remodeling my house right now and am putting in LEDs wherever possible. Even with a 75% efficient AC-DC converter, the LEDs are much more energy efficient than incandescents and halogens. They can be dimmed by reducing the current across the diode (the D in LED), which is essentially the same as lowering the voltage over the bias resistor. But in practice they can also be dimmed by PWM, which is really simple to implement and is more energy efficient than using a variable input voltage (won't get into why, but just accept it. . .)



    Right now I'm working on customizing some off-the-shelf lutron dimmers to handle the task of LED dimming for interior lighting.



    We seem to be using the word "dim" differently.



    I'm just refering to the natural dimming from degeneration of the gates, and you are talking about the dimming from deliberately wanting to change the light level.



    I've bought an LED unit that consists of two 10" units, an attachment cable for them, and a transformer. It is expensive! it cost $125. But it is bright! I used it to illuminate the turntable bay of the audio/video center I built.



    I also just bought a 20" unit from another company to see how well it works. It cost $39, and uses no transformer. I haven't opened it, but imagine it works the way I've designed LED units in the past, with current limiting resisters, and dioda to prevent ac from entering.



    It is not nearly as bright as the other two 10" units, but they also have 75% more LED's, and run them higher.
  • Reply 51 of 101
    melgrossmelgross Posts: 31,789member
    Quote:
    Originally Posted by JeffDM View Post


    I'll back you up on this. Efficiency varies with power input. You can pulse the light at its optimum efficiency point, and change the pulse width to vary its brightness. It's easier to dim them linearly with PWM because LEDs are not power-linear devices but you can linearly change the pulse width. Retinal physiology also shows that very fast pulsing lights makes them "seem" nearly as bright even if they are on 50% of the time. One might not notice the pulsing, but nearly every LED I've seen in a device is pulsed. I think there are other reasons too.



    That's not always done. And there has been some controversy about LED lifetime. The theory is complex, but some think that the higher voltages required in pulsing reduces the life. Others disagree. Testing is still going on.
  • Reply 52 of 101
    melgrossmelgross Posts: 31,789member
    Quote:
    Originally Posted by JeffDM View Post


    Aren't fluorescents also rated by a half-life?



    Not usually. Sometimes they are. Depends on the type. But the ones you are likely to encounter are rated 'till blowout.



    Most of the 50% ratings are not the official lifetime ratings. They are simply giving one an idea, in applications that it might be useful to know it, what the performance will be over time.



    You might as well rate incandescents that way as well, as they also dim with age.



    The difference is that LEDs might not burn out for a century or more if run at moderate levels.
  • Reply 53 of 101
    melgrossmelgross Posts: 31,789member
    Quote:
    Originally Posted by Booga View Post


    I'd just like to say that dimming LEDs by blinking them fast should be banned! It gives me a headache, and when I'm behind a new Cadillac is extremely distracting as my eye moves across the field of vision. I think I'd have seizures (not really, but I'd feel like having one) if I walked into a house where the LEDs dimmed by blinking.



    Some people are sensitive to that, though most are not.



    It's like the rainbow effect from the color wheel used in DLP's. Most people never notice it, but some do.



    It's thought to be a gene, believe it or not!
  • Reply 54 of 101
    jeffdmjeffdm Posts: 12,946member
    Quote:
    Originally Posted by Booga View Post


    I'd just like to say that dimming LEDs by blinking them fast should be banned! It gives me a headache, and when I'm behind a new Cadillac is extremely distracting as my eye moves across the field of vision. I think I'd have seizures (not really, but I'd feel like having one) if I walked into a house where the LEDs dimmed by blinking.



    I understand that. Just about every light source and display "blinks". Incandescent and fluorescent "blink" too, but they are less abrupt. Plasma, LCD, DLP generally blinks too. At least LEDs can be set to blink in the kilohertz range, where most other lights cycle at the same as their electricity, 50 or 60 Hz.
  • Reply 55 of 101
    tbagginstbaggins Posts: 2,306member
    Quote:
    Originally Posted by anantksundaram View Post


    I hate to rain on this back-slapping party, but I must admit to being rather stunned by the self-referential nature of the conversation here -- if someone came in from the outside (say, PC) world, they would be laughing out loud over the excitement amongst a handful of digiterati over a (supposedly) brighter screen.



    Since when have Apple fans ever given two figs what PC folks think?



    I think that's what really hacks off the PC crowd, and makes them think of us as 'smug' (to directly quote my PC-lovin' office mate). Well, that and the fact that the iPhone blew away pretty much anything and everything that was shown off by the PC industry at CES (unless you count Vista, or, as its starting to be referred to, 'OS X for PCs').



    You gotta accept the fact that the Apple crowd is very different from the PC crowd, and that has never bothered us.



    8)
  • Reply 56 of 101
    Quote:
    Originally Posted by Booga View Post


    I'd just like to say that dimming LEDs by blinking them fast should be banned!.



    Adding to JeffDM: No human can perceive discrete pulses anywhere near the frequencies commonly used for LED PWM (pulse width modulation). If you're curious, PWM is a simple concept and I bet there's a fine Wiki page on it. For the record, CCFL backlights are also pulsed, as are the actual pixels in displays.
  • Reply 57 of 101
    jeffdmjeffdm Posts: 12,946member
    Quote:
    Originally Posted by Splinemodel View Post


    No human can perceive discrete pulses anywhere near the frequencies commonly used for LED PWM (pulse width modulation).



    I can see most LED blinks, but usually not by just staring at them. If I ever glance in a direction of an LED, I can see the trail of dots. It's not something that bothers me though. The main kind of LED that bothers me are the blue ones, they are usually allowed to shine too brightly. I had a computer case with one that could shine through three layers of masking tape.
  • Reply 58 of 101
    I welcome new technology that can provide more even color and better battery life. However I must be in the minority because I have absolutely no use for a brighter screen. The MacBook and Pro models are enough of an improvement over the dim PowerBooks for me and I find I can't work on most modern desktop LCDs without turning the brightness way down, near zero on some models.



    On the sales side, the entire computer market is moving to notebooks, placing mobility above performance and ergonomics. I should invest my retirement savings in health care. Apple's shift to notebooks is coming faster than other manufacturers because their notebooks are powerful and well priced, while their desktop offerings lack the most popular PC configuration: a reasonably priced tower.
  • Reply 59 of 101
    solipsismsolipsism Posts: 25,726member
    Quote:
    Originally Posted by JeffDM View Post


    I can see most LED blinks, but usually not by just staring at them. If I ever glance in a direction of an LED, I can see the trail of dots. It's not something that bothers me though. The main kind of LED that bothers me are the blue ones, they are usually allowed to shine too brightly. I had a computer case with one that could shine through three layers of masking tape.



    I find that when chewing food, especially crunchy food, I can see the lights jumping. It's quite annoying as this occurs with no other light source.
  • Reply 60 of 101
    Quote:
    Originally Posted by solipsism View Post


    I find that when chewing food, especially crunchy food, I can see the lights jumping. It's quite annoying as this occurs with no other light source.



    Yeah, what is that? I remember noticing that as a child, and I used to get my mom to try to "see it" with me because I thought there was something wrong with my clock radio.



    If that happens with these new LEDs, we're going to have a new generation of Mac users who are even crazier than we are!!
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