1. This forum section is a read-only archive which contains old newsgroup posts. If you wish to post a query, please do so in one of our main forum sections (here). This way you will get a faster, better response from the members on Motherboard Point.

which colour LCD C-STN/TFT/TFD?

Discussion in 'Embedded' started by Ajab, Aug 30, 2007.

  1. Ajab

    Ajab Guest

    Which LCD should I choose? C-STN or TFT? Or any other LCD?
    I know TFT are expensive and they consume more power, but they provide
    superior image quality.
    I need to choose color LCD which is clearly visible from 10mm glass.
     
    Ajab, Aug 30, 2007
    #1
    1. Advertisements

  2. We have used various monochrome STN and color TFT. No direct experience
    with the C-STN, but the mono STN have been quite noisy. Needed extra
    filtering on some control lines. This may also be a concern if a
    touch-screen is in use.

    Scott
     
    Not Really Me, Aug 30, 2007
    #2
    1. Advertisements

  3. Ajab

    John Speth Guest

    Which LCD should I choose? C-STN or TFT? Or any other LCD?
    I think you should choose TFT.

    JJS
     
    John Speth, Aug 30, 2007
    #3
  4. You didn't give anywhere near sufficient details to allow an answer to
    that question.

    Just think for a moment: if there were a well-defined answer to such a
    broadly put question, how could all the other types of LCDs still
    survive in the market?
     
    Hans-Bernhard Bröker, Aug 30, 2007
    #4
  5. Ajab

    Ajab Guest

    I don't know much about LCDs.
    I just need to choose a colour LCD which is clearly visible from 10mm
    glass.
    Cost is not a problem. What else criteria I need to tell?
     
    Ajab, Aug 31, 2007
    #5
  6. Ajab

    Don McKenzie Guest

    have you thought about OLED's then?
    http://www.dontronics-shop.com/home.php?cat=371

    lots of youtube videos for our LCD's and OLED's, see:
    http://www.dontronics-shop.com/pages.php?pageid=59


    is an OLED video

    Don...


    --
    Don McKenzie

    Site Map: http://www.dontronics.com/sitemap
    E-Mail Contact Page: http://www.dontronics.com/email
    No More Damn Spam: http://www.wizard-of-oz.com

    Serial OLED uses standard micro-SD memory cards.
    http://www.dontronics-shop.com/product.php?productid=16659

    USB Flash Drive interface for existing products.
    http://www.dontronics-shop.com/product.php?productid=16654
     
    Don McKenzie, Aug 31, 2007
    #6
  7. Ajab

    Ajab Guest

    Why should I go for OLEDs? Are they better that TFT?
     
    Ajab, Aug 31, 2007
    #7
  8. Ajab

    Tom Lucas Guest

    They are brighter and use less power. But they are expensive and come in
    limited sizes.

    TFT would be best for you I would guess.
     
    Tom Lucas, Aug 31, 2007
    #8
  9. Ajab

    Don McKenzie Guest

    yes:
    http://www.dontronics.com/oled.html
    Cheers Don...


    --
    Don McKenzie

    Site Map: http://www.dontronics.com/sitemap
    E-Mail Contact Page: http://www.dontronics.com/email
    No More Damn Spam: http://www.wizard-of-oz.com

    Serial OLED uses standard micro-SD memory cards.
    http://www.dontronics-shop.com/product.php?productid=16659

    USB Flash Drive interface for existing products.
    http://www.dontronics-shop.com/product.php?productid=16654
     
    Don McKenzie, Aug 31, 2007
    #9
  10. John Devereux, Aug 31, 2007
    #10
  11. Ajab

    DJ Delorie Guest

    Depends on the color. Based on OSRAM's specs, yellow seems to have
    the longest lifetime, at 50k hours (that's 100% brightness, 100% of
    the time, until it drops to 50% lumens). Other colors are as low as
    10k hours, or just over a year. Note that this is a fundamental of
    LEDs themselves, not just OLEDs, but you only really notice the
    problem when it appears as "burn-in" on the display.

    However, note that some oled manufacturers are dropping their display
    lines. A lot of their oled matrix displays are either already
    obsolete, or will be out of production soon. Check with the
    manufacturer before designing them in.

    OLEDs also cost more than LCDs; a 2.7" 128x64 monochrome (16 levels)
    display is $37 (qty 1).

    If cost isn't an issue, also check out VFDs. They're even more
    expensive ($165 for that size) but, like OLEDs, they're emissive vs
    reflective (i.e. the elements themselves produce light, rather than
    blocking a backlight like LCDs do) so "off" is *really* off, and on is
    really on. This comes in handy when the display will be used in a
    dark room, as you don't get the "glowing grey rectangle" effect that a
    backlit LCD has.
     
    DJ Delorie, Aug 31, 2007
    #11
  12. Ajab

    DJ Delorie Guest

    Er, of course my experience is with monochrome displays, not full
    color. Not sure if VFD is an option in full color.
     
    DJ Delorie, Aug 31, 2007
    #12
  13. 50k hours is equivalent to most industrial CCFL LCD backlights -
    although you can change those!

    I think one of the OLED application notes I saw gave a lifetime
    *assuming a certain percentage* "on" time - so you have to be careful
    to read the small print.
    It does seem like they are still very much niche products. Still much
    more expensive than LCD when I last looked (a few months ago).
    I quite like VFD - the last time I had one was ~25 years ago in one of
    the early pocket calculators. Much nicer than the later LED and LCD
    displays. Funny they still have a role to play, considering the
    revolution in display technology since then.
     
    John Devereux, Aug 31, 2007
    #13
  14. Ajab

    DJ Delorie Guest

    Well, you can change an OLED too, I suppose.
    IIRC mine spec'd 100% on, 100% duty cycle. So my app is careful to
    use the minimum lumens required for the task, since the display *will*
    be on 100% of the time.

    Plus, the app note suggested moving the image around over time, to
    even out the wear and avoid burn-in.
    Yeah, too bad. I have a niche requirement that they fit just
    perfectly. Good thing I only need a few :)
    Noritake has a line of VFDs that are drop-in replacements for standard
    LCD panels, now. www.noritake-elec.com

    So perhaps it's just that the demand *in general* is so high, that
    niche products become profitable?
     
    DJ Delorie, Aug 31, 2007
    #14
  15. We noticed ;-)
    I'll assume you mean _through_ 10 mm of glass. Well, that's a bit more
    than usual to put in front of an LCD panel, but no particular burden.
    Let's see: size, resolution, op./non-op. thermal range, mechanical
    ruggedness, long-time stability, ambient brightness, update speed,
    available power --- and I'm quite sure I missed some important criteria.
     
    Hans-Bernhard Bröker, Aug 31, 2007
    #15
  16. If it's behind 10 mm of glass, I'd bet it's going into a hazardous area
    enclosure. Make sure it isn't too far behind the glass, or you can have
    parallax problems and glare. Make sure to try viewing the display under
    direct sun, and with polarized glasses on. I've come across some POS
    terminals that got the polarization "wrong", so the display is
    completely black with my shades on; I would have to bend my neck 90
    degrees to read it.

    --Gene
     
    Gene S. Berkowitz, Sep 1, 2007
    #16
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.