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Direct view HD-ready sets do not have ultra high effective resolution - they typically can't actually display much more information than 800x600 or 800x1080i. Increasing the resolution requires punching more/smaller holes in the shadow mask. Too many holes means too small holes and the image will be too dim.


However, the dimmest direct view set is a blazing torch of light compared to the brightest RPTV, right? So, why not punch more holes until either the light output is reduced to the level of the brightest RPTV or the effective resolution starts approaching the better RPTV's? If there was a direct view set that had super high resolution but required a dimmed room, I'd be tempted to buy one.


As it is, direct view sets have too much contrast, IMO. The people on the screen glow, and you get a strong 3D effect from the contrast, but the overall effect is what some refer to as hyper-reality, giving me an uneasy feeling. IMO, people should look more like reflected sunlight than direct blazing sunlight.


So, why not a finer shadow mask with a dimmer picture?


Sony sets and certain others use an aperture grill instead of a shadow mask. The grill is comprised of vertical wires, stablized by the infamous two horizontal wires. The XBR400 reportedly has just 721 wires in its aperture grill. Why don't they try a finer aperture grill on Trinitron-style sets?



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Abdul
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Quote:
Originally posted by Abdul Jalib:

However, the dimmest direct view set is a blazing torch of light compared to the brightest RPTV, right?
Are you sure about that? There are professional and computer-monitor hi-res CRTs, but they're not particular bright. Plus, they have rather low deflection angles, so they tend to be deep.


Making smaller holes also means the mask must be thinner, due to etching technology considerations. This makes the mask distort much easier due to heating from electron absorption (the mask itself absorbs ~75% of the beam current in these designs). Distortion due to heating also makes registration trickier. So the current has to be kept even lower. Plus, there are size limitations over how big an area you can make such a thin, hi-res mask, and keep it in registration.


There's a limited market for such small, dim direct-view CRTs, so the low volume keeps prices high.




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I keeping wishing for the same thing.


The Sony FW900 is a fully 1920x1080i capable direct view CRT

but it is "only" 24" wide. It has approx .26mm pixel pitch.


The larger 34" direct view "HDTV" sets (Panasonic, Toshiba, Sharp, etc.) have something like .8mm dot pitch which gives them a max res of around 1200x800 so they don't show the sharpest possible picture.


I wish (like you said) they would make some 34"+ direct views with around .4mm dot pitch so they could show the full 1080i signal in all its glory.


Based on other discussions I have had on AVSforum, I think we would be very happy if we got a monitor that was able to

well display around 1600x1000 since very little (if any) HDTV content actually uses all 1920 pixels on a 1080i line.

(some say most of the cameras are only good for about 1440 across)


I bet there are some complexities and cost problems involved with producing 34"+ direct view CRTs with that sort of small dot pitch, but this industry is filled with challenges waiting to be met.


By the way - the Trinitron aperture grille doesn't always have two wires to hold the grille stable. The smaller models (e.g. 16") tend to have only one wire. If they did a 34" .4mm pitch version I bet it would need 3 or more wires.


(In case anyone doesn't already know, you can see these horizontal wires very faintly if there is a bright image on screen)
 
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