Anamorphic lenses for crt?

Discussion in 'Projectors, Screens & Video Processors' started by cosaw, Apr 11, 2004.

  1. cosaw

    cosaw
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    On reading discussion about fixed height 2.35:1 screens on the AVSForum and since searching within the DLP/LCD forum I have found some reference to anamorphic lenses.

    Are these available for CRT pjs? On searching the forum didn't find any info, is anyone running such a setup. If the lenses exist are they expensive?

    Obviously, this would allow you to use a full 4:3 phosphor area for different (wider) aspect ratios. What effects would this have? Presumably it would increase overall brightness in tandem with increasing tube life/limiting wear patterns? What effect would an anamorphic lens have on scan lines, would it be the same as the anamorphic squeeze on a pj or different?

    Simon
     
  2. Chris Frost

    Chris Frost
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    boosting light output with an anamorphic lens is an interesting idea, but I think you'll have difficulty finding anyone offering a product.

    CRT is much more versatile than fixed lens projection. If your projector can scan high enough and has a small enough beam spot size then you can draw any aspect ratio across the phosphor and tailor the scanning resolution to suit.

    I wonder just how big each of the three anamorphic lenses would have to be to cope with the lens diameter of a typical 9" tubed projector? ;)

    Regards
     
  3. cosaw

    cosaw
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    Being fairly new to crt I just wondered - you know. Afterall the answer could have been : "yes it's quite common". Don't know much about lens technology but I gather from your comments that anamorphic lenses would be somewhat more hefty than normal ones, and on reflection I suppose that figures.

    Thanks for the info Chris :smashin:

    Simon
     
  4. Roland @ B4

    Roland @ B4
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    Anmorphic lenses are incredibly inefficint anything you gain from such a lens if it existed you would loose later in optical performance.

    Have you thought of having two machines side by side using the whole phophor area but edge blending. This would be amazingly bright and sharp.
     
  5. cosaw

    cosaw
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    I suppose the loss in optical performance would be due to how accurately the lens was crafted? I assume that an anamorphic lens is a difficult thing to make in a cost effective manner with good results. I have a slight astigmatism in my right eye and any tailored prescription for glasses gives me migraines. I tend to wear my contact lenses which don't correct my astigmatism but don't give me the headaches. If opticians can't figure it on the small scale I suppose even greater problems are introduced on the large scale ;)

    I wish! I'm still saving for and dreaming about my first CRT; I just like to theories/fantasise about these things sometimes. :)

    Simon
     
  6. Roland @ B4

    Roland @ B4
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    Here's an idea. use a 4x3 screen to use all the phosphor. then fit really strong anamorphic contact lenes.
    Several instant advantages
    Instant wide screen.
    Room would look bigger.

    Wife would look wider Ah! ( I know rotate the lenses she would then be taller and slimmer)
     
  7. Blighty_Boy

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    ROTLMAO :laugh: :clap: :laugh: :clap: :smashin:
     
  8. cosaw

    cosaw
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    Yep, I certainly had a chuckle, at my expense it would seem :laugh: ;)

    Simon
     
  9. Roland @ B4

    Roland @ B4
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    Not at all it was a valid point.
    It is physically possible to produce both long throw and anamorphic lenses for CRT's just not econimically viable.

    BTW what ever happened to XRay specs that allowed you see through walls and clothes. but not quite through underwear?
     
  10. cosaw

    cosaw
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    I know you were only yanking my chain.

    We've already got em - didn't you see "The World Is Not Enough"? However since Desmond Llewelyn (Q) is no longer with us we're not going to get the extra levels of visual depth that were proposed. Second layer fabric penetration being one of them. :D

    Here's the reality if your interested: http://www.mindcontrolforums.com/x-rayspecs.htm

    Simon
     
  11. rob_w

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    Roland were you being serious about this - do people do it ?

    Can you imagine the high def possibilities of two 1280x960 res pj's next to each other? - and of course for me another data 800 would upgrade me to 1600x1200 :devil:

    Would you need 2 graphic cards in 1 hcpc ?

    Cheers

    Rob
     
  12. cosaw

    cosaw
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    You mean two crts side by side, yes I beleive it's done. I think there are a couple of threads on the AVScience forum, concentrating on edge blending issues etc.

    Simon
     
  13. rob_w

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    Interesting - I'll do a search there....:smashin:

    Rob
     

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