Palm patents the dual-mode color/monochrome screen

[Alexander Turcic]

So here is the scoop: To enhance the battery life of a mobile device, Palm had the ingenious idea to take away the color of your screen when battery power is dwindling down. Before the technocrats among you indulge in sneers and laughter, listen to how US patent 7002569 describes it:

In one embodiment, the electronic device is a hand held computer system with a display device. When the battery level is detected as below a preselected level, a message is generated on the computer display screen. The message informs the user that the display mode of the screen can be changed to enhance the battery life. If selected, the display mode can change from color to monochrome thereby saving power because the monochrome display does not utilize a back-lighting element. In one embodiment, color sequential techniques are used to provide a flat panel color display. Within the display, a transreflective layer provides reflective light for monochrome applications. When the battery energy returns to normal levels, the color display mode can be re-entered automatically. It is appreciated that the display mode changes can also be performed automatically if the battery level falls below certain critical levels.

Attached you find a diagramm which illustrates this invention. As you perhaps know, the biggest drain on mobile devices is the LCD screen; and the single greatest culprit that contributes to an LCD's power usage is the backlight. Every transreflective LCD is backlit by a small, fluorescent (CCF) tube. The brighter you want your screen to be, the harder that tube has to work. The energy it takes to power that tube in what the industry considers a "typical" setting accounts for roughly 75 percent of the total LCD power usage.

This is where Palm's invention comes into play. Once the system detects that the battery runs low, it turns your device's screen from color to monochrome. This effectively reduces battery consumption of the display by up to 75 percent as monochrome screens don't require the backlight to stay on. Once your battery is being recharged and exceeds a predetermined level again, the system automatically places the display back into color mode. One thing's for sure: the monochrome display may not only give you more power to pass the time while you're bored on the subway or waiting for the movie to start, but it will also stir a nostalgic rush of good old memories.

[Snappy!]

Frankly, between battery life and color, I'll go for battery life. I hope they include a manual override to allow users to toggle color/mono mode anytime. I would switch to mono and use it as an eBook reader!

[TadW]

According to the patent, you can either automatically or manually toggle color/mono.

[morituri]

Isn't this the same type of screen which was proposed for Nicholas Negroponte's $100 dollar laptop project? It has a lower res colour screen which could switch to a higher res monochrome setting for reading ebooks, outdoors use and lower power consumption.

[hacker]

SWEET! They actually took another one of my ideas (yep, this is clearly validated by prior art discussed about 4 years ago or longer on irc, just when color devices were rumored to be coming out).

I basically said that it would be neat for them to make a device which could use paper-white greyscale to save battery life and extend the use of the device, when you're not near a charger, or when doing something like reading a long novel, where color isnt' an issue.

Damn, where was my $10k when I needed to file a patent to block this. I also said (back in the late 90's, also verified on irc logs of probably a dozen or more people on #palmchat at the time), that the silkscreened-on graffiti area of the PalmIII was a waste of space, and they should just make it out of pixels and have it slide out of the way when you don't need it, and gain that glass area back for applications. Enter "Virtual Graffiti" 5 years later.

Damn damn damn! (and no, this is NOT an April Fool's joke, I'm completely serious about this, as anyone who can recall me ranting about it years ago can attest).

[luag]

close to my idea...which is a dual color lcd/eink display
i should patent my idea as soon as possible

[Pride Of Lions]

Good job, Alexander! A very thorough and convincing April Fool's.

Of course I could be wrong, but (despite my recent PPC leanings) I just think Palm is still trying to catch up to the "Innovation" train. With all these PPC vendors out there competing with each other one of them would have come up with this to trump the others if it were possible.

[Alexander Turcic]

Originally Posted by Pride Of Lions

Good job, Alexander! A very thorough and convincing April Fool's.

I swear, this is not an April Fool's!

[Pride Of Lions]

I was picturing you at your keyboard in October crafting the perfect April Fool's joke for us and researching patent-speak to make it sound even more authentic.

I guess in October you were thinking of October stuff and not so much April stuff. Oh well, now next year I'll believe anything you post because I don't think you have a sense-of-humor.

[Alexander Turcic]

Originally Posted by Pride Of Lions

I guess in October you were thinking of October stuff and not so much April stuff. Oh well, now next year I'll believe anything you post because I don't think you have a sense-of-humor.

I promise that next year, I'll turn a true patent into a ridiculous April joke to prove that even I can have a sense of humor.

[maceyr]

I'm not sure if this is such as smart thing to do. Most times, you just have to turn off the backlight when in bright sunlight and you should be able to "see" what's on the screen if at an angle.

[Chaos]

Originally Posted by maceyr

I'm not sure if this is such as smart thing to do. Most times, you just have to turn off the backlight when in bright sunlight and you should be able to "see" what's on the screen if at an angle.

In the sunlight, true... but we're not always in bright sunlight. When looking at a colour display, you almost always (except as you noted, at an angle in the sun) need a backlight of some sort to use it. I remember an old IBM laptop I played around with when I was young (like... 11), which had no backlight (burned out). The display was very close to being totally unusable. I ended up taking it apart for the fun of it, since I didn't have an extra monitor lying around at that time.

Monochrome displays, however, as seen with old Palm models, are almost completely usable without a backlight - you only need some sort of front-light (a flashlight, a ceiling light, the sun, whatever) to read it. I'd much rather have that when I'm looking up an e-mail address or reading a book, at the greatly reduced power consumption, than a full-colour backlight display.