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Can one "overclock" a CRT monitor's video input bandwidth? Need slightly higher refresh rate than m

Discussion in 'Overclocking' started by Ken Moiarty, Apr 19, 2006.

  1. Ken Moiarty

    Ken Moiarty Guest

    My 19" Viewsonic A90's vertical refresh rate peaks [email protected] 100 Hz for a
    resolution of 1024 x 728. For stereo 3-D video viewing purposes, I need it
    to display at this resolution at a bare minimum vertical refresh rate of
    approximately 120 Hz (though preferabley when I get another monitor, at
    about 170 Hz). I could go out and buy another 19" monitor which purports to
    be able to achieve the former for only about $250 (CAD) right now; in which
    case the current CRT monitor will be gently laid to rest. So since it no
    longer matters what happens to my present CRT monitor since I'm going to
    replace it anyway, can I ask: Is there any way to over-ride the monitor's
    built in refresh rate limitations (e.g. by tweaking some knobs at the back,
    or even inside, or by making simple modifications to a component(s) -only of
    course with the guidance and asistance of a licensed monitor technician due
    to obvious safety reasons)? Aside from the risk of electrocution to those
    who'd be foolhardy enough to attempt such an undertaking on their own
    without the proper training and qualifications to go inside a monitor, is
    it in any way technically feasible, given the right personnel, and done
    cautiously and gradually (much like a CPU overclocker takes a high risk
    gamble with the investment in his PC) to raise the monitor's refresh rate a
    little beyond factory default and (say, if given extra cooling) be able to
    keep it there indefinitely?

    Sorry if my words above haven't come out quite right. It's late and I'm a
    little punchy at the moment.

    TIA,
    Ken
     
    Ken Moiarty, Apr 19, 2006
    #1
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  2. Ken Moiarty

    Mark M Guest

    Ken, good quality CRTs are going for next to nothing on eBay and
    just about everywhere else. With a little searching (e.g. company
    moving/going out of business/etc sales are great for this) you should
    be able to knock that $250 down to under $100. Trying to increase
    the bandwidth on your existing CRT will cost MUCH more in
    component cost and soldering time.
     
    Mark M, Apr 19, 2006
    #2
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  3. Ken Moiarty

    J. Clarke Guest

    I'm assuming that you have a modern CRT with microprocessor controls that
    displays "signal out of range" or words to that effect when it gets a
    signal that is beyond its rated capabilities and your intent is to alter
    the limit beyond which that signal appears.

    To do that you'd have to reprogram the control processor, which means
    identifying it, finding the firmware ROM, pulling the program off of it,
    disassembling it, analyzing it, and then figuring out how to tweak it to
    make the change you want.

    This would be weeks or months of work for a professional programmer familiar
    with that particular processor's assembly language--coming in cold you're
    going to have to learn that before you can do anything, and if you have no
    programming experience assembler is generally not the best place to start
    learning. You'll also need equipment that costs about the same as a new
    monitor to be able to read and reprogram the ROM.

    And once you've done that the analog components that actually do the work
    are not going to be up to the task of handling that bandwidth--you'll get
    any of several kinds of image degradation.

    If you are _paying_ somebody to do this then the cost is going to be
    enormous. By the time you're done you'll likely have paid enough to get a
    containerload of new CRTs.

    If you've got a hundred thousand machines out in the field all with the same
    monitor and you want to try working up a mod for the monitor rather than
    replacing them all then this _might_ be worth trying with the understanding
    that there is no guarantee of a successful outcome, but even if the mod
    itself is completely successful there opening each monitor and replacing
    the ROM is likely to come perilously close to the cost of a new monitor.

    For just one monitor, the only justifications I can think of for doing it
    are that you want to learn something for your own satisfaction, you just
    plain enjoy dinking around with such things, and neither of these is a
    sound business reason.
     
    J. Clarke, Apr 19, 2006
    #3
  4. No, there is no practical way to do this without extremely
    extensive reworking of the circuit design and components.
    This is NOT practical even for people who work on high-
    voltage CRT circuits all the time, much less for people like
    us who only dabble.

    The major limiting factor is the horizontal sweep frequency,
    and then the frequency response of the video path. The second
    of those factors COULD be modified to get higher frequency-
    response, but boosting the horizontal sweep frequency is just
    not practical for most people. It very likely would involve
    modification or replacement of the two most critical components
    in the whole circuit (the deflection yoke and the flyback
    transformer).

    Richard Crowley in rec.video.desktop
    Note that this is not really on-topic for r.v.d which is
    chartered for discussion of television editing, which
    appears to have nothing to do with your question.
    Hopefully, you will get more expert advice from one
    of the more on-topic newsgroups.
     
    Richard Crowley, Apr 19, 2006
    #4

  5. There are literally tons of free, good used monitors out there for
    the asking. I picked up seven of them last Thursday at one place. They
    were the last items from this year's upgrades. That office maintains a
    little over 1000 PCs all over the county, and replaces 200 older working
    systems every year, along with some upgrades. I requested 100 complete
    computer systems from next years upgrades and was told they would call
    me when they started again in the fall.



    One of the monitors I picked up is a HP 1130 Professional Monitor
    which is a 21" monitor:

    Featuring cutting-edge FD Trinitron® technology, the HP p1130 CRT
    monitor delivers the ultimate in image quality and user comfort. With
    resolutions up to 2048 x 1536 and no image flicker, this monitor is
    ideal for graphics-intensive applications including desktop publishing,
    design, engineering, software development, image processing, and digital
    content creation as well as general office applications such as
    spreadsheets and presentations.

    (The above excerpt from the HP website file: hpP1130DataSheet.pdf)

    BTW: It also has a second video input and front panel switch to use
    it with two computers or video cards. I will be using it to write code
    on so I can display more information at once.





    --
    Service to my country? Been there, Done that, and I've got my DD-214 to
    prove it.
    Member of DAV #85.

    Michael A. Terrell
    Central Florida
     
    Michael A. Terrell, Apr 19, 2006
    #5
  6. Another thought: is there a video card that would be able to create the
    desired signal?

    One might have to hack the video card's firmware as well as the
    monitor's.

    Sounds like fun to me...well, maybe not.

    Just curious -
    Gino
     
    Gene E. Bloch, Apr 19, 2006
    #6
  7. Ken Moiarty

    Phil Weldon Guest

    'Ken Moiarty' wrote, in part:
    | My 19" Viewsonic A90's vertical refresh rate peaks [email protected] 100 Hz for a
    | resolution of 1024 x 728. For stereo 3-D video viewing purposes, I need
    it
    | to display at this resolution at a bare minimum vertical refresh rate of
    | approximately 120 Hz (though preferabley when I get another monitor, at
    | about 170 Hz).
    ..
    | Is there any way to over-ride the monitor's built in refresh rate
    limitations
    | (e.g. by tweaking some knobs at the back, or even inside, or by making
    | simple modifications to a component(s) -only of course with the guidance
    | andasistance of a licensed monitor technician due to obvious safety
    | reasons)?
    _____

    Your question posted is 'Can one "overclock a CRT monitor's video input
    bandwidth?' with the qualification of 'Need slightly higher refresh rate
    than by existing CRT allows...'.

    First, changing the VERTICAL refresh rate changes the HORIZONTAL rate. The
    horizontal rate for 1024 X 728 at 100 Hz vertical refresh is just a bit more
    than 728 X 100 = 72,800 Hz; the horizontal rate for 1024 X 728 at 120 Hz
    vertical refresh is just a bit more than 728 X 120 = 87,360. The real
    limiting factor is the horizontal rate, it is a high power circuit that
    drives magnetic coils to sweep the electron beam from side to side. The
    same circuit also develops the high voltage (15,000 to 20,000 volts) power
    to accelerate the electrons toward the screen.

    So it is not just the frequency response of the video amplifiers, which,
    except for the final driver stages, run on milliwatts. It is a question of
    the horizontal sweep circuits that account for 90% of the power used by a
    CRT monitor. It is not a question of cooling, it is not like overclocking a
    CPU or display adapter - it is more like trying to drive a Trabant at
    autobahn speeds.

    You might try 1280 X 720 at 120 Hz; 720 X 120 = 86,400 Hz horizontal sweep
    rate, a bit lower than 1024 X 120 Hz. I tried this setting on my Viewsonic
    A95f 19" monitor (I had to uncheck the 'Hide modes this monitor cannot
    display' box on the 'Monitor' Tab reached clicking on the 'Advanced' button
    on the display properties sheet. It works at 1280 X 720 at 120 Hz, though
    the screen needs quite a bit of adjustment and the images are not as good as
    on the same monitor at 1600 X 1200 at 85 Hz.

    You can also run the display card/monitor at a lower vertical resolution say
    960 X 600 at 120 Hz; 600 X 120 Hz = 72,000 or 1088 X 612 at 120 Hz; 612 X
    120 = 73,440. Both of these resolutions have lower horizontal refresh rates
    at 120 Hz than 1024 X 768 at 100 Hz. (Uncheck the box 'Hide modes this
    monitor cannot display.

    My Viewsonic is protected from unreasonable horizontal rates - at a setting
    of 1024 X 768 at 120 Hz no image displays until after the 15 second time out
    and the display adapter reverts to the previous good resolution and vertical
    refresh rate. I assume your model is also, so give it a try, and let us
    know the results.

    Phil Weldon


    | My 19" Viewsonic A90's vertical refresh rate peaks [email protected] 100 Hz for a
    | resolution of 1024 x 728. For stereo 3-D video viewing purposes, I need
    it
    | to display at this resolution at a bare minimum vertical refresh rate of
    | approximately 120 Hz (though preferabley when I get another monitor, at
    | about 170 Hz). I could go out and buy another 19" monitor which purports
    to
    | be able to achieve the former for only about $250 (CAD) right now; in
    which
    | case the current CRT monitor will be gently laid to rest. So since it no
    | longer matters what happens to my present CRT monitor since I'm going to
    | replace it anyway, can I ask: Is there any way to over-ride the monitor's
    | built in refresh rate limitations (e.g. by tweaking some knobs at the
    back,
    | or even inside, or by making simple modifications to a component(s) -only
    of
    | course with the guidance and asistance of a licensed monitor technician
    due
    | to obvious safety reasons)? Aside from the risk of electrocution to those
    | who'd be foolhardy enough to attempt such an undertaking on their own
    | without the proper training and qualifications to go inside a monitor, is
    | it in any way technically feasible, given the right personnel, and done
    | cautiously and gradually (much like a CPU overclocker takes a high risk
    | gamble with the investment in his PC) to raise the monitor's refresh rate
    a
    | little beyond factory default and (say, if given extra cooling) be able to
    | keep it there indefinitely?
    |
    | Sorry if my words above haven't come out quite right. It's late and I'm a
    | little punchy at the moment.
    |
    | TIA,
    | Ken
    |
    |
     
    Phil Weldon, Apr 19, 2006
    #7
  8. Ken Moiarty

    Jasen Betts Guest

    I can dial up pretty much any sync rate I could desire from mine

    I'm not sure if S3 was the first to come out with programmable clock chips,
    (in the early 90s) but now pretty-much all video cards allow the pixel clock
    to be varied in reasonably small increments (smaller than 1%), and the
    horizontal and vertical clocks are derived from the pixel clock and provide
    a further opportunity to fine-tune the sync rates.
    SVGATextMode (a neat linux app to tweak video clocks for text mode displays)
    can be compiled for dos (with a little work). nothing much else uses the
    card's firmware...
    Bye.
    Jasen
     
    Jasen Betts, Apr 20, 2006
    #8
  9. Ken Moiarty

    Ken Moiarty Guest

    Well I think I get the gist of the answer to my query: "There's no point".
    Based on all (which I didn't know until now) that would be involved, I can
    of course only agree.

    Thanks all,
    Ken
     
    Ken Moiarty, Apr 20, 2006
    #9
  10. Ken Moiarty

    Phil Weldon Guest

    'Ken Moiarty' wrote:
    | Well I think I get the gist of the answer to my query: "There's no point".
    | Based on all (which I didn't know until now) that would be involved, I can
    | of course only agree.
    _____

    Thanks for replying. Do try one of the modes I suggested and let us know
    your results with the Viewsonic A90.

    Phil Weldon

    | Well I think I get the gist of the answer to my query: "There's no point".
    | Based on all (which I didn't know until now) that would be involved, I can
    | of course only agree.
    |
    | Thanks all,
    | Ken
    |
    |
     
    Phil Weldon, Apr 20, 2006
    #10
  11. Ken Moiarty

    Ken Moiarty Guest

    For resolution 1280 x 1024 my CRT monitor maxes out @ 85 Hz vertical
    refresh rate. Any higher refresh rate for this resolution and my monitor
    gives me a basically blank screen containing the message "signal out of
    range". I wait 15 seconds after that and the setting then returns to what
    it was previously. 1280 x 1024 @ 85 Hz used to work just fine for me, until
    I had to move out of my rented living accomodations, and into a house that I
    actually co-own together with my sister since several years back.
    Now, to answer your questions regarding trying the different settings,
    first a preamble: In case you hadn't followed the other thread I posted in
    this group, I need to explain: This house is located as close as any house
    can be legally built to a major (three tower wide) high-voltage powerline
    easement. In fact part of the easement spills right into my property. The
    60 Hz AC current in these powerlines generates a weak, but significant
    oscillating magnetic field which is just strong enough to distort and
    disrupt CRT image performance that is not running at the same frequently of
    60 Hz. That's is okay for viewing TV video (especially since one obviously
    cannot typically change one's TV refresh rate from its factory preset of 60
    Hz, even if one wanted to), but is kind of bothersome for the up close
    viewing as when using a computer monitor. Thus I actually bought an LCD
    monitor to side step this PL interference problem entirely for my daily
    computer tasks. Anyway, back to the subject... In an effort to counter the
    PL interference, I've experimented by temporarily setting my monitor to
    (unacceptably) low resolution settings (e.g. 640 x 480) so as to be able to
    achieve and test much higher refresh rates. What I've discovered is that at
    refresh rates of around approx. 120 Hz and above, the interference on the
    screen diminishes to a level that is barely perceptible.
    While there is no CRT interference experienced at the 60 Hz setting, 60
    Hz refresh rate is not acceptable for my main purpose here, in which, I'm
    aiming be able to view high-quality, high-resolution, stereo 3-D
    video --i.e. employing LCD shutter-glasses, etc. (My other purpose is to
    use this CRT along side my LCD as a second monitor providing for an extended
    Windows desktop.) High-quality, high-resolution, Stereo 3-D video will
    actually require refresh rates of something above 120 Hz (e.g. 130 to 144
    Hz) at resolutions ranging from 1024 x 768 up to 1280 x 1024. However, the
    highest refresh rate I can achieve at a resolution that is the bare minimum
    acceptable for my purposes here (i.e. 1024 x 768) is only 100 Hz. (BTW,
    further to the above paragraph, 100 Hz provides some, although inadequate,
    improvement in noticeable interference compared to the 85 Hz setting.) Of
    course 100 Hz is far short of the > 120 Hz refresh rates I'm going to need
    here.

    Now just to be clear here, I have in fact accepted the fact that in
    order to get the kind of "high refresh rate to high resolution" performance
    I'm after here I'm simply going to have to buy a good monitor that offers
    this capability. In other words, I'm no longer entertaining the
    "overclocking of my existing CRT monitor" idea. One monitor model
    I'm thinking at the moment of possibly getting is a "22" (20" viewable)
    iiyama HM204DT. It's video input bandwidth is 390 MHz. Displays 1280 x 1024
    at 133 Hz... MSP: $699 USD. Hoping to find _equivalent_ (of at least as
    good, if not better, value) alternative CRT products/models so that I can
    at least do some comparison shopping here before taking the plunge. I'm
    open to product suggestions from anyone here in this vein...

    Ken


    PS: Someone, I forget who, suggested that my monitor "resolution to
    refresh rate" options were limited perhaps not by the monitor itself, but
    by, either, my adapter card or its default settings (which supposedly, I
    guess, might not occur to some people to change). This is not the case. I
    have explored all the valid settings that my adapter provides. And while
    it's hardly a very expensive adapter, according to its specs it is capable
    of displaying, for example 1024 x 768 @ 150 Hz. If the monitor could only
    keep up, such a setting would basically suffice.
    Of course, to find an adapter card capable of displaying the higher
    resolution of 1280 x 1024 at such a desired high refresh rate poses no
    concern to me in any way, as such high performance adapter cards are, both,
    quite affordable, as well as easy to shop for. Still, no use in buying one
    of these until I get a CRT monitor that is capable of taking advantage of
    the performance parameters which my choice of new adapter card will be
    intended to support.

    TIA,
    Ken
     
    Ken Moiarty, Apr 21, 2006
    #11
  12. Ken Moiarty

    Phil Weldon Guest

    'Ken Moiarty' wrote, in part:
    | For resolution 1280 x 1024 my CRT monitor maxes out @ 85 Hz vertical
    | refresh rate.

    My Viewsonic A95f ALSO maxes out at 85 Hz for 1280 X1024. BUT, it will do
    1280 X 720 @ 120 Hz. I suggested you try that resolution and vertical
    refresh rate with your Viewsonic A95 as a temporary workaround for 3D.

    As for the effect of the high tension lines, without knowing what you see on
    your screen, if what you see is a faint rolling bar, I'd have to guess that
    it is not the magnetic field of the lines, but the interference induced in
    your house AC feed, or even in the house wiring.

    Phil Weldon


    | For resolution 1280 x 1024 my CRT monitor maxes out @ 85 Hz vertical
    | refresh rate. Any higher refresh rate for this resolution and my monitor
    | gives me a basically blank screen containing the message "signal out of
    | range". I wait 15 seconds after that and the setting then returns to what
    | it was previously.
     
    Phil Weldon, Apr 21, 2006
    #12
  13. Now that you mention stereo...

    I have seen reference recently to a new LCD panel design allowing for
    viewing stereo directly by what seems to be an analog of the stereo
    photos that use a grid of cylindrical lenses in front of a still photo,
    where the left and right pictures are successive vertical stripes, and
    the grid of lenses directs the appropriate stripe's data to the 'right'
    eye.

    I forget where I saw it or who was working on it; maybe Samsung.

    The bottom line is that maybe this kind of display would have milder
    refresh requirements for stereo viewing.

    The bad thing is I have no idea if this is already happening or still
    being developed.

    Gino

    PS. The LCD I mention doesn't use lenses, but physical barriers that
    prevent one eye from seeing the pixels intended for the other eye.

    PPS. I was one of those who mentioned possible limits on the video
    card's capabilities. I admit that it was speculation on my pert - sort
    of trying to be a messenger of doom and gloom, I guess :)

    On 4/21/2006, Ken Moiarty posted this:
     
    Gene E. Bloch, Apr 21, 2006
    #13
  14. Ken Moiarty

    Ken Moiarty Guest

    Okay, I'm trying the 1280 x 720 @ 120 Hz as we speak. It works. I wasn't
    motivated to try it at first as 1280 x 720 resolution is video wide screen
    (16:9 aspect ratio) format and as far as I'm aware (at least at this stage
    in my pursuit of stereo 3-D video), most (if not all) high-resolution stereo
    3-D video content available is from IMAX film productions which match the
    video standard (4:3 aspect ratio) screen format.
    No, no... Nothing like that.
    Well I've explained this to once skeptical others before you, times too
    numerous to recount. Let's just say here that if it can't be the
    oscillating magnetic field from the power lines -which, by the way, produces
    other interesting effects around the house, like bright blue 'star-like'
    arcing between the aluminum soffit panels which can be seen any evening
    after dark (a soffit grounding * issue I have yet to have repaired)- then
    the local city engineers who've seen to it that it be required by law that
    the aluminum gutters, the aluminum window frames, the sheet-steel
    central-heating ducts, and all other significant metallic surfaces of houses
    such as mine (i.e. those being right next to such major powerlines), * must
    have special grounding, don't know what they're doing. (Of course, I mean
    this remark tongue-in-cheek.)

    * {Being that it is oscillating, not unlike that created mechanically by
    the rotating permanent-magnet containing armature of a generator, this
    magnetic field from the PL is capable of inducing currents in these close
    proximity metallic forms. These in turn can pose a fire hazard due to
    inevitable charge buildup and the arcing that results in the absence of
    effective special-purpose grounding to drain off this charge buildup. Now,
    while having described why how this is so, the induction of electrical
    current in metal surfaces is _not_ the same process that is responsible for
    the oscillating magnetic field's interference with my CRT monitor (which is
    actually due to its having a _direct_ influence on the CRT's electron-beam
    trajectory, which thereby adds to, or 'contaminates', the otherwise
    delicately synchronized and cleanly precise internal control of said beam's
    scanning of the phosphor screen), it illustrates just how actually
    significant the oscillating magnetic field originating from these powerlines
    in fact is, at this close range.}

    Ken
     
    Ken Moiarty, Apr 22, 2006
    #14
  15. Ken Moiarty

    Ken Moiarty Guest

    Yes, I've read about this technology. Apparently it has been developed well
    enough (as of a while ago already) to produce LCD monitors capable of
    displaying full stereo 3-D video without requiring the wearing of
    shutter-glasses by the viewer(s). This is done with with the use of these
    cylindrical lenses as you describe, which are called if I recall,
    "lenticular lenses". Lenticular lenses, if I understand correctly, have
    been used with still images for many years now, for example, producing 3-D
    or "holographic" images as are common on credit cards, driver's licenses,
    Microsoft software security logos, etc...etc... You can actually buy
    software that will enable you to print images in such a way that when you
    accurately affix the associated special plastic lenticular lens sheet over
    top of the printed image, it will then appear in 3-D.) In the case of the
    3-D LCD panels, as you describe, lenticular lenses are placed over
    corresponding alternating "left field" and "right field" LCD columns. If I
    recall the only major hurdle left to overcome has been figuring out how to
    market it to the masses so enough people will want to buy it in order that
    it can be manufactured on an economy of scale large enough such that it can
    be priced just right in order to generate the consumer demand for it to make
    it profitable... (A common catch-22 of marketing to consumers many a novel
    invention/technology, I would think.)

    Ken
     
    Ken Moiarty, Apr 22, 2006
    #15
  16. Ken Moiarty

    J. Clarke Guest

    Lenticular screens produce a kind of 3d effect but it is different from a
    hologram. The images that are used as security features on credit cards
    are usually holograms--I'm not sure what Microsoft is using but the
    presence of shadows suggests lenticular.

    Lenticular screens were around when I was a kid, before the laser had been
    invented. Holograms came along later--I made some as a senior physics
    project. In the art world the lines between them are not distinct, in the
    physics world they are very clear.
     
    J. Clarke, Apr 22, 2006
    #16
  17. Thanks, John, for adding this clarification to the discussion.

    I just looked at two MS installation CDs. Their top surfaces are quite
    clearly holograms. I don't seem to have any stickers on the boxes so I
    can't comment about their stickers.

    What I read about the stereo LCD monitors included diagrams showing
    that the videos for the two eyes were separated by barriers, not
    controlled by cylindrical lenses.

    BTW, "lenticular" just means "lens-shaped", although it could just as
    easily mean "bean shaped" :), since "lens" comes directly from the
    Latin word for lentil. The term might have been "lenticular ridges" or
    some such...

    Gino
     
    Gene E. Bloch, Apr 22, 2006
    #17
  18. Think carefully before buying an Iiyama 22" CRT monitor. I've
    owned the A201HT and the HA202-DT and a colleague has a
    something-203-something. All three are somewhat blurry at
    1600 x 1200 due to convergence problems. I was unable to correct
    this through the OSD.

    Their 19" CRT monitors are OK. Their 22" CRT monitors look good
    on paper (good specs for the money) but your eyes might not like
    them.

    hardware.fr recently tested three CRT monitors : the Philips
    109B60 (19"), ViewSonic P227FB (21") and Iiyama MA203DT (22").
    They found the same thing I did ; the Iiyama is blurry. They
    recommended the ViewSonic.

    http://www.hardware.fr/articles/613-1/der-der-comparatif-crt.html
    http://www.behardware.com/articles/613-1/the-last-crt-survey.html
     
    Andre Majorel, Apr 22, 2006
    #18
  19. Ken Moiarty

    Jasen Betts Guest

    No, not those 3d images those are real holograms produced using laser
    photography, and mass produced using a photographically etched stamp and a
    layer of metal, the images have a prismatic effect producing all the
    coulours of the rainbow dependant on viewing angle and lighting conditions..

    the 3d images produced using the lenticular grating are fabricated using
    specially textured layer of plastic with a specially formatted image printed
    using ordinary ink on ordinary paper behind it. they are about 1mm thick.
    often the images are cartoon-like drawings and appear with real colours.
    In the case of the
    could a sheet be placed over the front of a regular LCD display.
    with 24-bit-per-pixel video each colour bar is individually
    addressible (in its own byte) which simplifies the software.
    it'd just be a matter of calibration, and apropriate drivers then.

    I realise that if the lenticular sheet is integral it reduces those sort of
    hassles, but it seems to create a demand an entry level solution might work
    better.

    Bye.
    Jasen
     
    Jasen Betts, Apr 22, 2006
    #19
  20. Ken Moiarty

    Ken Moiarty Guest

    And hence why I wrote "hologram" in quotation marks...
    Okay if such security features are literally holograms (as opposed to
    lenticular, as I had reasoned 'by default' they must be), then I must plead
    ignorance in regards to my understanding of these. In my cursory
    understanding of holography, I thought one had to _utilize a laser_ not only
    to take a holographic photograph, but also to view the photographed
    holographic image (or hologram).

    What's relatively new here is the LCD video display technology that's been
    perfected and brought to market over the last few years, which, unlike the
    older motion picture technologies of film and CRT, happens to be easily
    adapted for use with lenticular lenses for displaying 3-D video (i.e.
    without special paraphernalia).
    Yes, I'm well aware that holograms and lenticular screens are distinctly
    different entities. But it has seemed to me that the term, "hologram" is
    has become borrowed frequently enough in popular (albeit scientifically
    inaccurate) consumer-level usage, to be understood to refer in general to
    many a printed still image that merely resembles a hologram in appearance.
    But then again, maybe all this time I'm the only one to have gotten this
    impression; and that what I've frequently interpreted in pop tech media
    (e.g. Popular Science Magazine, Discover, for example, etc...) to be merely
    a loose co-opting of the term "hologram" for sake of mainstream-journalistic
    convenience, has maybe in fact been intended to be understood as technically
    literal after all. (Hmm..??)

    Ken
     
    Ken Moiarty, Apr 23, 2006
    #20
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