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Adjusting display on Dell 8100?

B

BillW50

Flightless Bird
Barry Watzman wrote on Thu, 21 Jan 2010 18:31:58 -0500:
> They do not call them pixels, and they are not pixels.


During my electronic engineering classes and in the consumer market, we
called the three different primary phosphors as a pixel. LCDs were not
available yet. But when they were and when we heard they used pixels
too, it was a no brainer.

> The electron beam of a CRT is not sufficiently well focused and does not
> have sufficiently sharp edges (the edges are "fuzzy") to actually turn
> on and off individual phosphor dot triads.


Let's get one thing straight. Color CRTs have three electron guns. One
for red, one for green, and one for blue. And the red, green, or blue
guns can only fire at the same color phosphor or it is all wrong (which
is one third of a pixel). This error is known as convergence.

> There are no fixed pixels on
> a CRT; pixels are formed by turning on and off the electron beam as it
> sweeps.


False! The groups of color phosphor is fixed. Manufactures group them
differently, but you can see them with a magnifying glass (I'm so near
sighted, I can see them without one). Color CRTs has always had pixels
as far as I have been alive. I never counted them, but I am sure they
are in the hundreds or more in both directions.

> If you turn it on and off 640 times as it goes across the
> screen, you have a 640 pixel display; if you turn it on and off 800
> times, an 800 pixel display (the pixels are smaller), and 1024 and 1280
> and so on. But to work well and produce a visually high quality image,
> the "pixels" so formed need to encompass MULTIPLE phosphor dot triads,
> e.g. phosphor dot triads (a single set of one each red, blue and green
> phosphor) are much smaller than pixels. If you drive the resolution to
> a point where this is not true, the image quality goes to hell very
> quickly because, again, the focus and edge sharpness of the electron
> beam don't ALLOW it to actually address a single phosphor dot triad.


Sounds like you are confusing monochrome with color to me. Color CRTs
pixels are fixed and you can't change them. It all depends on the
individual CRT. Much like you can't change the native LCD resolution.

> BTW, I have worked for both computer mfgrs. and TV mfgrs. and in
> broadcasting, since the 1960's. I worked for Zenith, and as a broadcast
> engineer, and as a product manager for computer displays (both CRT and
> LCD). I know what I'm talking about here.


And I have worked for Zenith and Magnavox on the consumer end and
Philips and Hitachi for the professional market.

> Sure you can show blown up pictures of an image on a phosphor dot CRT
> and see the individual phosphor dots. But those are not pixels. Really,
> they are not. There are NO physical pixels on a CRT.


They were called pixels as far as I have been alive. And *only* computer
color CRT monitors were rated by pitch. Color TVs had pitch too, but I
never seen them rated as such. And pitch was the distance between the
pixels. The earlier ones was awful, at .52 pitch (normally CGA quality).
Then they got better at .28 and I think down to .21 and then they
stopped advertising the pitch. I don't know why they stopped. Maybe it
was so fine that most people couldn't see any difference anymore anyway.

> [Also, consider a monochrome (B&W) CRT; it has no individual dots at all
> in the phosphor coating, but you can blow up a character image on such a
> tube and see individual dots. They are "painted" on an absolutely
> continuous coating by turning the electron beam on and off. It forms
> dots .... but they are not physical entities.]


Monochrome is totally different. The whole screen is one single layer of
phosphor covering the whole screen. Like paint if you like to think of
it that way. There are no pixels per se in monochrome CRTs at all.

Although if somebody wants to argue that monochrome also has pixels
too... well it isn't quite the same thing as color CRTs and LCDs. But
somebody could generate a checkerboard pattern smaller and smaller and
just before it turns all gray and claim this is the max pixel resolution
of a given CRT. It would be hard for me to argue against it. But I would
rather call it the max resolution instead. As there is no individual
pixels that you could actually count per se.

> BillW50 wrote:
>> Barry Watzman wrote on Wed, 20 Jan 2010 23:43:55 -0500:
>>> No bill; a phosphor dot triad is not the same thing as a pixel. A
>>> pixel is larger and for proper operation will cover multiple phosphor
>>> dot triads.

>>
>> Really? Then how do you explain every tech journal, every textbook,
>> every instructor, every TV tech, and any engineer I ever met calls
>> them pixels? And did you ever bother to visit this site I posted
>> earlier? It was in the very same post you replied to. With pictures no
>> less. They call them pixels too. So what you are saying is the whole
>> world is wrong, right?
>>
>>> BillW50 wrote:
>>>> http://express.howstuffworks.com/exp-tv1.htm

>>



--
Bill
Asus EEE PC 702G4 ~ 2GB RAM ~ 16GB-SDHC
Xandros Linux (build 2007-10-19 13:03)
 
B

Barry Watzman

Flightless Bird
Phosphor dot triads is the correct term for an individual set of RGB
phosphor dots on a shadow mask type color CRT. THEY ARE NOT AND NEVER
WERE PIXELS. Anyone who calls them pixels is using terminology
improperly. Pixel is short for "picture element"; a clear requirement
for a pixel is the ability to discretely turn it on and off. You can't
do that with a phosphor dot triad. The electron beam is too large, and
has edges that are too "fuzzy"; at any given time, the electron beam is
probably driving 3 to possibly 10 or 20 phosphor dot triads, depending
on the resolution of the image and the dot pitch of the CRT.

[Yes, I know that a shadow mask CRT has separate electron beams for red,
blue and green phosphors. But what you called "convergence" is actually
color purity. Color purity is whether the RGB beams only hit the RGB
phosphors; Convergence is slightly different, it is WHICH RGB phosphors
(of the proper color) the 3 beams hit ... the set is "converged" if the
hit the dots of the same triads.]

Look, you are just wrong; you know a lot but not as much as you think
you do. Ok, I'm done wasting my breath telling you that. Others who
are knowledgeable can recognize that you don't fully know what you are
talking about. And you can go on fooling those who know less than you
do, it doesn't effect me.

But you don't understand the distinction between a color CRT phosphor
dot triad and a pixel, and consequently you have a whole lot of things
very subtly (but significantly) confused.


BillW50 wrote:
> Barry Watzman wrote on Thu, 21 Jan 2010 18:31:58 -0500:
>> They do not call them pixels, and they are not pixels.

>
> During my electronic engineering classes and in the consumer market, we
> called the three different primary phosphors as a pixel. LCDs were not
> available yet. But when they were and when we heard they used pixels
> too, it was a no brainer.
>
>> The electron beam of a CRT is not sufficiently well focused and does
>> not have sufficiently sharp edges (the edges are "fuzzy") to actually
>> turn on and off individual phosphor dot triads.

>
> Let's get one thing straight. Color CRTs have three electron guns. One
> for red, one for green, and one for blue. And the red, green, or blue
> guns can only fire at the same color phosphor or it is all wrong (which
> is one third of a pixel). This error is known as convergence.
>
>> There are no fixed pixels on a CRT; pixels are formed by turning on
>> and off the electron beam as it sweeps.

>
> False! The groups of color phosphor is fixed. Manufactures group them
> differently, but you can see them with a magnifying glass (I'm so near
> sighted, I can see them without one). Color CRTs has always had pixels
> as far as I have been alive. I never counted them, but I am sure they
> are in the hundreds or more in both directions.
>
>> If you turn it on and off 640 times as it goes across the screen, you
>> have a 640 pixel display; if you turn it on and off 800 times, an 800
>> pixel display (the pixels are smaller), and 1024 and 1280 and so on.
>> But to work well and produce a visually high quality image, the
>> "pixels" so formed need to encompass MULTIPLE phosphor dot triads,
>> e.g. phosphor dot triads (a single set of one each red, blue and green
>> phosphor) are much smaller than pixels. If you drive the resolution
>> to a point where this is not true, the image quality goes to hell very
>> quickly because, again, the focus and edge sharpness of the electron
>> beam don't ALLOW it to actually address a single phosphor dot triad.

>
> Sounds like you are confusing monochrome with color to me. Color CRTs
> pixels are fixed and you can't change them. It all depends on the
> individual CRT. Much like you can't change the native LCD resolution.
>
>> BTW, I have worked for both computer mfgrs. and TV mfgrs. and in
>> broadcasting, since the 1960's. I worked for Zenith, and as a
>> broadcast engineer, and as a product manager for computer displays
>> (both CRT and LCD). I know what I'm talking about here.

>
> And I have worked for Zenith and Magnavox on the consumer end and
> Philips and Hitachi for the professional market.
>
>> Sure you can show blown up pictures of an image on a phosphor dot CRT
>> and see the individual phosphor dots. But those are not pixels.
>> Really, they are not. There are NO physical pixels on a CRT.

>
> They were called pixels as far as I have been alive. And *only* computer
> color CRT monitors were rated by pitch. Color TVs had pitch too, but I
> never seen them rated as such. And pitch was the distance between the
> pixels. The earlier ones was awful, at .52 pitch (normally CGA quality).
> Then they got better at .28 and I think down to .21 and then they
> stopped advertising the pitch. I don't know why they stopped. Maybe it
> was so fine that most people couldn't see any difference anymore anyway.
>
>> [Also, consider a monochrome (B&W) CRT; it has no individual dots at
>> all in the phosphor coating, but you can blow up a character image on
>> such a tube and see individual dots. They are "painted" on an
>> absolutely continuous coating by turning the electron beam on and
>> off. It forms dots .... but they are not physical entities.]

>
> Monochrome is totally different. The whole screen is one single layer of
> phosphor covering the whole screen. Like paint if you like to think of
> it that way. There are no pixels per se in monochrome CRTs at all.
>
> Although if somebody wants to argue that monochrome also has pixels
> too... well it isn't quite the same thing as color CRTs and LCDs. But
> somebody could generate a checkerboard pattern smaller and smaller and
> just before it turns all gray and claim this is the max pixel resolution
> of a given CRT. It would be hard for me to argue against it. But I would
> rather call it the max resolution instead. As there is no individual
> pixels that you could actually count per se.
>
>> BillW50 wrote:
>>> Barry Watzman wrote on Wed, 20 Jan 2010 23:43:55 -0500:
>>>> No bill; a phosphor dot triad is not the same thing as a pixel. A
>>>> pixel is larger and for proper operation will cover multiple
>>>> phosphor dot triads.
>>>
>>> Really? Then how do you explain every tech journal, every textbook,
>>> every instructor, every TV tech, and any engineer I ever met calls
>>> them pixels? And did you ever bother to visit this site I posted
>>> earlier? It was in the very same post you replied to. With pictures
>>> no less. They call them pixels too. So what you are saying is the
>>> whole world is wrong, right?
>>>
>>>> BillW50 wrote:
>>>>> http://express.howstuffworks.com/exp-tv1.htm
>>>

>
>
 
B

BillW50

Flightless Bird
In news:hjdcsv$gac$1@news.eternal-september.org,
Barry Watzman typed on Fri, 22 Jan 2010 18:38:02 -0500:
> Phosphor dot triads is the correct term for an individual set of RGB
> phosphor dots on a shadow mask type color CRT. THEY ARE NOT AND NEVER
> WERE PIXELS. Anyone who calls them pixels is using terminology
> improperly. Pixel is short for "picture element"; a clear requirement
> for a pixel is the ability to discretely turn it on and off. You
> can't do that with a phosphor dot triad. The electron beam is too
> large, and has edges that are too "fuzzy"; at any given time, the
> electron beam is probably driving 3 to possibly 10 or 20 phosphor dot
> triads, depending on the resolution of the image and the dot pitch of
> the CRT.
> [Yes, I know that a shadow mask CRT has separate electron beams for
> red, blue and green phosphors. But what you called "convergence" is
> actually color purity. Color purity is whether the RGB beams only
> hit the RGB phosphors; Convergence is slightly different, it is WHICH
> RGB phosphors (of the proper color) the 3 beams hit ... the set is
> "converged" if the hit the dots of the same triads.]
>
> Look, you are just wrong; you know a lot but not as much as you think
> you do. Ok, I'm done wasting my breath telling you that. Others who
> are knowledgeable can recognize that you don't fully know what you are
> talking about. And you can go on fooling those who know less than you
> do, it doesn't effect me.
>
> But you don't understand the distinction between a color CRT phosphor
> dot triad and a pixel, and consequently you have a whole lot of things
> very subtly (but significantly) confused.


Sorry Barry! I worked 10 years on electron microscopes and scanning
electron microscopes which are nothing but large and expensive CRTs.
And electron beams can be focused down to the size of a single atom, if
needed (that is the limit). What you are talking about is so old school
and so outdated. Here read this below for example. It is a bit newer
than what you are saying.

<<< QUOTE >>>

A large part of the efforts being directed at improving the CRT's image
are aimed at creating a beam with less spread, so that the beam can
address smaller individual dots on the screen more accurately - that is,
without impinging on adjacent dots. This can be achieved by forcing the
beam through smaller holes in the electron gun's grid assembly - but at
the cost of decreasing the image's brightness. Of course, this can be
countered by driving the cathode with a higher current so as to liberate
more electrons. However, doing this causes the barium that is the source
of the electrons to be consumed more quickly and so reduces the life of
the cathode.

Sony's answer to this dilemma is SAGIC, or small aperture G1 with
impregnated cathode. This comprises a cathode impregnated with tungsten
and barium material whose shape and quantity has been varied so as to
avoid the high current required for a denser electron beam consuming the
cathode. This arrangement allows the first element in the grid - known
as G1 - to be made with a much smaller aperture, thus reducing the
diameter of the beam that passes through the rest of the CRT. By early
1999 the technology had helped Sony reduce its aperture grill pitch to
0.22mm - down from the 0.25mm of conventional Trinitron tubes - the
tighter beam and narrower aperture grill working together to provide a
noticeably sharper image.

http://www.pctechguide.com/42CRTMonitors_Electron_beam.htm

<<< UNQUOTE >>>

So as you can see, the electron beam can be focused down to a single
pixel. In this example, down to .22mm.

The distance between the pixels are measured in pitch. Both CRTs and
LCDs are measured this way. And I already showed you references that
showed color CRTs uses pixels. So you are not arguing with me, but the
rest of the known world. I don't make this stuff up you know. And when
you say I don't know what I am talking about, you are saying the rest of
the world doesn't know what they are talking about either.

And if you don't still believe us, all you have to do is to open up a
blank document on a decent CRT screen and take a magnifying glass and
move the pointer around. And you can see individual pixels light up and
off. This isn't rocket science you know. Any 5 year old kid could easily
check this out.

Here is everything you ever wanted to know about pixels (including CRT
pixels)
http://www.answers.com/topic/pixel

And even PC World calls them CRT pixels
http://www.pcworld.com/article/15765/how_it_works_crt_monitors.html

Google "CRT pixel" and you get over a million hits.

Planar calls CRT elements as pixels.
http://www.planar3d.com/3d-technology/lcd-vs-crt/

The list goes on and on! It isn't me saying this, but the entire world
is saying it as well.

Sorry!

> BillW50 wrote:
>> Barry Watzman wrote on Thu, 21 Jan 2010 18:31:58 -0500:
>>> They do not call them pixels, and they are not pixels.

>>
>> During my electronic engineering classes and in the consumer market,
>> we called the three different primary phosphors as a pixel. LCDs
>> were not available yet. But when they were and when we heard they
>> used pixels too, it was a no brainer.
>>
>>> The electron beam of a CRT is not sufficiently well focused and does
>>> not have sufficiently sharp edges (the edges are "fuzzy") to
>>> actually turn on and off individual phosphor dot triads.

>>
>> Let's get one thing straight. Color CRTs have three electron guns.
>> One for red, one for green, and one for blue. And the red, green, or
>> blue guns can only fire at the same color phosphor or it is all
>> wrong (which is one third of a pixel). This error is known as
>> convergence.
>>> There are no fixed pixels on a CRT; pixels are formed by turning on
>>> and off the electron beam as it sweeps.

>>
>> False! The groups of color phosphor is fixed. Manufactures group them
>> differently, but you can see them with a magnifying glass (I'm so
>> near sighted, I can see them without one). Color CRTs has always had
>> pixels as far as I have been alive. I never counted them, but I am
>> sure they are in the hundreds or more in both directions.
>>
>>> If you turn it on and off 640 times as it goes across the screen,
>>> you have a 640 pixel display; if you turn it on and off 800 times,
>>> an 800 pixel display (the pixels are smaller), and 1024 and 1280
>>> and so on. But to work well and produce a visually high quality
>>> image, the "pixels" so formed need to encompass MULTIPLE phosphor
>>> dot triads, e.g. phosphor dot triads (a single set of one each red,
>>> blue and green phosphor) are much smaller than pixels. If you
>>> drive the resolution to a point where this is not true, the image
>>> quality goes to hell very quickly because, again, the focus and
>>> edge sharpness of the electron beam don't ALLOW it to actually
>>> address a single phosphor dot triad.

>>
>> Sounds like you are confusing monochrome with color to me. Color CRTs
>> pixels are fixed and you can't change them. It all depends on the
>> individual CRT. Much like you can't change the native LCD resolution.
>>
>>> BTW, I have worked for both computer mfgrs. and TV mfgrs. and in
>>> broadcasting, since the 1960's. I worked for Zenith, and as a
>>> broadcast engineer, and as a product manager for computer displays
>>> (both CRT and LCD). I know what I'm talking about here.

>>
>> And I have worked for Zenith and Magnavox on the consumer end and
>> Philips and Hitachi for the professional market.
>>
>>> Sure you can show blown up pictures of an image on a phosphor dot
>>> CRT and see the individual phosphor dots. But those are not pixels.
>>> Really, they are not. There are NO physical pixels on a CRT.

>>
>> They were called pixels as far as I have been alive. And *only*
>> computer color CRT monitors were rated by pitch. Color TVs had pitch
>> too, but I never seen them rated as such. And pitch was the distance
>> between the pixels. The earlier ones was awful, at .52 pitch
>> (normally CGA quality). Then they got better at .28 and I think down
>> to .21 and then they stopped advertising the pitch. I don't know why
>> they stopped. Maybe it was so fine that most people couldn't see any
>> difference anymore anyway.
>>> [Also, consider a monochrome (B&W) CRT; it has no individual dots at
>>> all in the phosphor coating, but you can blow up a character image
>>> on such a tube and see individual dots. They are "painted" on an
>>> absolutely continuous coating by turning the electron beam on and
>>> off. It forms dots .... but they are not physical entities.]

>>
>> Monochrome is totally different. The whole screen is one single
>> layer of phosphor covering the whole screen. Like paint if you like
>> to think of it that way. There are no pixels per se in monochrome
>> CRTs at all. Although if somebody wants to argue that monochrome also
>> has pixels
>> too... well it isn't quite the same thing as color CRTs and LCDs. But
>> somebody could generate a checkerboard pattern smaller and smaller
>> and just before it turns all gray and claim this is the max pixel
>> resolution of a given CRT. It would be hard for me to argue against
>> it. But I would rather call it the max resolution instead. As there
>> is no individual pixels that you could actually count per se.
>>
>>> BillW50 wrote:
>>>> Barry Watzman wrote on Wed, 20 Jan 2010 23:43:55 -0500:
>>>>> No bill; a phosphor dot triad is not the same thing as a pixel. A
>>>>> pixel is larger and for proper operation will cover multiple
>>>>> phosphor dot triads.
>>>>
>>>> Really? Then how do you explain every tech journal, every textbook,
>>>> every instructor, every TV tech, and any engineer I ever met calls
>>>> them pixels? And did you ever bother to visit this site I posted
>>>> earlier? It was in the very same post you replied to. With pictures
>>>> no less. They call them pixels too. So what you are saying is the
>>>> whole world is wrong, right?
>>>>
>>>>> BillW50 wrote:
>>>>>> http://express.howstuffworks.com/exp-tv1.htm


--
Bill
Gateway M465e ('06 era) - Windows XP SP3
 
B

BillW50

Flightless Bird
Here you go Barry! I found this:

Handbook of Display Technology
By Joseph A. Castellano

This book cost about $150. And according to Castellano, we are both
partially right and we are both partially wrong.

I was right about pixels and wrong about a pixel is a triad (true only
in LCD).

You were right about pixels are not a triad (in regards to CRT), but
wrong about CRTs of having pixels too.

Castellano explains that found in lots of textbooks and manufacture's
tech documents that a triad and a pixel are the same thing even when
talking about CRTs is simply wrong! As Castellano explains this isn't so
with CRTs. As the triads used in CRTs are far smaller than those used in
LCDs (I didn't know this, did you?).

Thus say you have a CRT that has .22mm pitch. This is one pixel
Castellano explains (nothing new for me here). Although this one pixel
can contain many triads (no surprise to you, eh?). So the resolution
isn't measured by the number of triads (only true of LCD so far), but by
the number of pixels (a pixel equals resolution, no surprise to me).

And I asked the question why doesn't CRTs have a native resolution like
LCDs has since they both have pixels? Which nobody has yet answered. And
now I believe I have the answer. That is because in order for a CRT to
have a native resolution, a pixel must equal one triad before this can
happen. And a pixel per triad is actually a big disadvantage.

So LCDs are far behind CRT technology when it comes to pixels. As CRTs
uses far more triads per pixel than LCDs. And the only way for LCDs to
catch up is to greatly make the triads much smaller like the ones used
in CRTs. In short, the triads are just too dang big in LCDs.

--
Bill
Gateway M465e ('06 era) - Windows XP SP3
 
T

the wharf rat

Flightless Bird
In article <hjdl4b$28b$1@news.eternal-september.org>,
BillW50 <BillW50@aol.kom> wrote:
>
>Google "CRT pixel" and you get over a million hits.
>


You should see what happens when you google "flying saucer".
 
B

Barry Watzman

Flightless Bird
BillW50 wrote:
> Here you go Barry! I found this:
>
> Handbook of Display Technology
> By Joseph A. Castellano
>
> This book cost about $150. And according to Castellano, we are both
> partially right and we are both partially wrong.
>
> I was right about pixels and wrong about a pixel is a triad (true only
> in LCD).
>
> You were right about pixels are not a triad (in regards to CRT), but
> wrong about CRTs of having pixels too.
>
> Castellano explains that found in lots of textbooks and manufacture's
> tech documents that a triad and a pixel are the same thing even when
> talking about CRTs is simply wrong! As Castellano explains this isn't so
> with CRTs. As the triads used in CRTs are far smaller than those used in
> LCDs (I didn't know this, did you?).
>
> Thus say you have a CRT that has .22mm pitch. This is one pixel
> Castellano explains (nothing new for me here). Although this one pixel
> can contain many triads (no surprise to you, eh?). So the resolution
> isn't measured by the number of triads (only true of LCD so far), but by
> the number of pixels (a pixel equals resolution, no surprise to me).
>
> And I asked the question why doesn't CRTs have a native resolution like
> LCDs has since they both have pixels? Which nobody has yet answered. And
> now I believe I have the answer. That is because in order for a CRT to
> have a native resolution, a pixel must equal one triad before this can
> happen. And a pixel per triad is actually a big disadvantage.
>
> So LCDs are far behind CRT technology when it comes to pixels. As CRTs
> uses far more triads per pixel than LCDs. And the only way for LCDs to
> catch up is to greatly make the triads much smaller like the ones used
> in CRTs. In short, the triads are just too dang big in LCDs.
>
 
B

Barry Watzman

Flightless Bird
I think you are misinterpreting what you are reading.

CRT's have "pixels" but they are "soft"; they are not physical entities
as they are on an LCD panel. The CRTs pixels are "painted" by the
electron beam (beams, ok?) as it (they) scan(s) across the phosphors, by
turning the beam on and off.

And because they are "soft", you can run the CRT at different
resolutions without any issues, until the number of pixels that you are
trying to create gets too small relative to both size of the phosphor
triads and, also various characteristics of the electron beam involving
it's diameter, shape and the "fuzziness" of it's edges.

[Your point about what is possible with an electron beam is accurate,
but not relevant. The electron beams in consumer grade color CRTs are
not of the "perfect focus", "sharp edged", "perfectly round" variety.
Is it possible to make such displays? Yes, but it's expensive, it's not
necessary for this application (consumer grade displays) and it's not done.]

A CRT (ok, a consumer grade CRT) CANNOT have 1 pixel = 1 triad because
you cannot individually address (turn on and off) the phosphor dot of a
single triad. Again, the electron beam is not that small, it's edges
are not that sharp, it's SHAPE is not suited to behaving in that manner
(indeed, it's shape is not even constant; an electron beam that is
almost perfectly circular in the dead center of a display tube almost
always becomes significantly elliptical when it is near the edges or
corner of the tube; it's just very hard (not impossible, but not cost
justified in consumer displays) to maintain that kind of focus and
control over the beams as they are deflected across an entire CRT screen).

And no, I don't agree with your last paragraph. There are simply
fundamental differences between color CRTs and LCD panels. They are
different TYPES of display, and those differences are INHERIT in the
display devices (LCD panels and CRT tubes) themselves. LCDs have
PHYSICAL pixels, CRTs have "soft" pixels which are not physical, e.g. no
manufacturing parameter or process corresponds to the resolution of the
CRT display tube. If there was a physical pixel in a CRT Display,
indeed, you would order different tubes, and therefore different
monitors, for different resolutions (as we do for LCD displays); but you
don't, do you, for CRT displays?

There is, however, a maximum resolution that any given CRT tube can
display, which is a function of the phosphor dot triad size relative to
the size, shape and sharpness of the electron beam. Basically, again,
you need several physical phosphor dot triads per "soft" pixel to
produce a good image, and once that ratio starts to get "small", image
quality deteriorates rapidly.



BillW50 wrote:
> Here you go Barry! I found this:
>
> Handbook of Display Technology
> By Joseph A. Castellano
>
> This book cost about $150. And according to Castellano, we are both
> partially right and we are both partially wrong.
>
> I was right about pixels and wrong about a pixel is a triad (true only
> in LCD).
>
> You were right about pixels are not a triad (in regards to CRT), but
> wrong about CRTs of having pixels too.
>
> Castellano explains that found in lots of textbooks and manufacture's
> tech documents that a triad and a pixel are the same thing even when
> talking about CRTs is simply wrong! As Castellano explains this isn't so
> with CRTs. As the triads used in CRTs are far smaller than those used in
> LCDs (I didn't know this, did you?).
>
> Thus say you have a CRT that has .22mm pitch. This is one pixel
> Castellano explains (nothing new for me here). Although this one pixel
> can contain many triads (no surprise to you, eh?). So the resolution
> isn't measured by the number of triads (only true of LCD so far), but by
> the number of pixels (a pixel equals resolution, no surprise to me).
>
> And I asked the question why doesn't CRTs have a native resolution like
> LCDs has since they both have pixels? Which nobody has yet answered. And
> now I believe I have the answer. That is because in order for a CRT to
> have a native resolution, a pixel must equal one triad before this can
> happen. And a pixel per triad is actually a big disadvantage.
>
> So LCDs are far behind CRT technology when it comes to pixels. As CRTs
> uses far more triads per pixel than LCDs. And the only way for LCDs to
> catch up is to greatly make the triads much smaller like the ones used
> in CRTs. In short, the triads are just too dang big in LCDs.
>
 
B

Barry Watzman

Flightless Bird
From Wikipedia, "Display Resolution":

"Also in analog connected picture displays such as CRT TV sets, the
horizontal scanlines are not divided into pixels ...."

"ultimately "display resolution" in CRT-type displays is affected by
different parameters such as [electron beam] spot size and focus,
astigmatic effects in the display corners [e.g. shape of the beam, which
is no longer round], the color phosphor pitch shadow mask ..."

"display resolution ... can be an ambiguous term especially as the
displayed resolution is controlled by all different factors in cathode
ray tube (CRT) and flat panel or projection displays using fixed
picture-element (pixel) arrays ..."



the wharf rat wrote:
> In article <hjdl4b$28b$1@news.eternal-september.org>,
> BillW50 <BillW50@aol.kom> wrote:
>> Google "CRT pixel" and you get over a million hits.
>>

>
> You should see what happens when you google "flying saucer".
>
 
M

~misfit~

Flightless Bird
Somewhere on teh intarwebs Barry Watzman wrote:
> I think you are misinterpreting what you are reading.

[snip]

LOL, they say that the best thing about banging your head against a wall is
the feeling of relief that you get when you stop.

I know the feeling.
--
Cheers,
Shaun.

"Give a man a fire and he's warm for the day. But set fire to him and he's
warm for the rest of his life." Terry Pratchet, 'Jingo'.

> BillW50 wrote:
>> Here you go Barry! I found this:

[snip]
 
B

BillW50

Flightless Bird
In news:hjjrue$shq$1@news.eternal-september.org,
~misfit~ typed on Mon, 25 Jan 2010 23:31:34 +1300:
> Somewhere on teh intarwebs Barry Watzman wrote:
>> I think you are misinterpreting what you are reading.

> [snip]


I actually didn't misinterpret anything. What Barry said is actually
what I said. And it is also nice that Barry now admits that CRT has
pixels. ;-)

--
Bill
Gateway M465e ('06 era) - Windows XP SP3
 
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