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Flat screen TV's and staining

Discussion in 'TVs' started by Ixon, Jul 23, 2002.

  1. Ixon

    Ixon
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    Why is that nearly all makes and brands TV's have some staining in one form or other. is it hard for a company to make the perfect tube.
     
  2. LV426

    LV426
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    Yes, when they have to be made down to a price, rather than up to a standard. Which is why, in a couple of years, true flat panels (eg LCD) will take over the wiorld.
     
  3. Zacabeb

    Zacabeb
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    The staining I have seen (dirty patches) has been exclusive to a particular brand of tube, beginning with Pa, that is randomly used in many other manufacturer's sets, such as the ones beginning with Ph, Th, and J. This particular brand of tube is also known for actually not being flat, but a regular tube with flat glass in front.

    It is also known for Ph having brutally taken credit for it in order to excuse their random use of it.

    [​IMG]
    It has been said to be made in the same factory, or actually two completely different factories connected by a 500km long secret tunnel. [​IMG] The green path in the map is not the tunnel, but the route mere mortals have to drive to get from the one end of this factory to the other. The only place where this tunnel is not a secret is in Idar-Oberstein.

    Putting two inches of leaded glass in a faceplate is bound to cause staining, no?
     
  4. LV426

    LV426
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    Staining, poor geometry, bad convergence, voltage "bounce" are all common artefacts of colour CRTs. To understand why, an understanding of how a colour CRT works is needed, and I don't have them time, and I suspect the webmasters wouldn't appreciate the space needed, to describe it all here.

    However, suffice to say that, actually, the less depth the tube has (ie from the screen on the front to the back of the "neck") in relation to its largest dimension (ie its diagonal) and the flatter the screen, the more complex the electronics have to be to produce a properly shaped and coloured picture. This is quite contrary to the marketing "spiel": flat screens mean less distortion. They don't.

    The ideal CRT has a screen which is a spherical section with a radius exactly the same as the distance from the screen to the yoke at the back. Such a screen would require little in the way of image processing to get a linear picture. It follows that, for a totally flat screen, the depth of the tube needs to be infinite.
     

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