The grid matrix on Dell's 1907FP 19" LCD drives me nuts

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kasnem

I just received a Dell 1907FP 19 inch LCD monitor. It has a very
visible grid matrix on the screen like a layer of nets that turns lines
into fuzzy dots. After a few hours of using it, my eyes is killing me.

I checked my previous Viewsonics VX700 17 inch LCD and there is no
such visible grid matrix on the screen. There are several possible
explanations:

1. The Dell 1907FP is using a grid matrix wire to provide current to
the pixels, the VX700 is using different technology which has less
visible grid matrix.

2. The VX700's dot pixel is only .25 mm and thus is less visible than
the 1907FP which has .294 mm dot pixel.

3. All of the above.

Anyone knows the reason why these two LCDs look so different?

(Most 19" LCD uses .294 mm dot pixels. Will a genric 20.1" LCD with
..255 mm dot pixel solve this problem?)
 
I just received a Dell 1907FP 19 inch LCD monitor. It has a very
visible grid matrix on the screen like a layer of nets that turns lines
into fuzzy dots. After a few hours of using it, my eyes is killing me.

I checked my previous Viewsonics VX700 17 inch LCD and there is no
such visible grid matrix on the screen. There are several possible
explanations:

1. The Dell 1907FP is using a grid matrix wire to provide current to
the pixels, the VX700 is using different technology which has less
visible grid matrix.

2. The VX700's dot pixel is only .25 mm and thus is less visible than
the 1907FP which has .294 mm dot pixel.

3. All of the above.

Anyone knows the reason why these two LCDs look so different?
2

(Most 19" LCD uses .294 mm dot pixels. Will a genric 20.1" LCD with
.255 mm dot pixel solve this problem?)
Click to expand...

Most likely yes, for you. Or you could just sit further away 8), so
you can't resolve the pixel structure.
 
chrisv said:
Most likely yes, for you. Or you could just sit further away 8), so
you can't resolve the pixel structure.
Click to expand...

One recommendation I get is turning down the brightness of the monitor
so that the grid matrix is less visible. I'll give it a try once I am
in the office.

I looked at all the LCD monitors in Frys. This is what I found:

1. All LCD monitors in Frys have less visible grid matrix than the Dell
1907FP sitting on my desk and thus cause less strain on the eyes. All
of them have similar dot pixel, which is barely visible. It could be
due to smaller dot pixel, different dox pixel, or less brightness. I
don't know the answer yet.

2. If we click start->"Help and Support" on each LCD monitor and check
the letters in the header in close distance, we can see four to five
dots "...." under letters such as "C" or "S", which are caused by the
grid matrix. These dots make the lines fuzzy and cause strain on
viewer's eyes. (One often felt tired after watching LCD for a few
hours). The traditional CRT monitor does not have these dots, which is
why CRT is simply sharper than LCD.
3. The dots under a letter on my Viewsonics VX700 is barely visible. It
is almost as good as a CRT. Newer 17" LCD I saw in Frys is not as good.
Maybe it's due to it's .25 mm dot pixel, or different structure.

Watching LCD monitor from distance is not a solution. Most LCD monitor
are viewed from 18" to 24". Farther than this, reading text become very
difficult.
 
My concern regarding LCD monitor is quite general, not specific to any
given model. The LCD monitor is like matrix printer in the old days,
the dots are often very visible. As we move from CRT to LCD, are we
aware of this big problem?

Manufactures sell LCD by emphasizing brightness, contrast, speed, etc.
The major drawback of visible grid matrix or dot pixel is hidden from
the public. The problem is solvable if it is recognized and dealt with.

One solution is obviously using smaller dot pixel less than .25 mm.
This will increase the cost, but at least one will get a monitor
comparable to CRT when one pays top dollar to buy top LCD model. If
this problem is not emphasized, we will continue to pay top dollar for
top model of LCD that is not suitable for reading text.

Do we really want to continue producing billion dollars worth of LCD
that hurt people's eyes in the office?
 
My concern regarding LCD monitor is quite general, not specific to any
given model. The LCD monitor is like matrix printer in the old days,
the dots are often very visible. As we move from CRT to LCD, are we
aware of this big problem?
Click to expand...

Hmm... Well, assuming the same "dot pitch", the LCD should not be
"inferior" to the CRT in this regard. However it may appear to be
because the CRT will, in general, be less precisely focused, thus
softening the image somewhat and making it easier on the eyes.

Another possibility are differences in the gaps between the "lit"
portions of the screen. I don't know if one of these two technologies
is superior in that regard. Maybe Bob will chime in here.
 
chrisv said:
Hmm... Well, assuming the same "dot pitch", the LCD should not be
"inferior" to the CRT in this regard. However it may appear to be
because the CRT will, in general, be less precisely focused, thus
softening the image somewhat and making it easier on the eyes.

Another possibility are differences in the gaps between the "lit"
portions of the screen. I don't know if one of these two technologies
is superior in that regard. Maybe Bob will chime in here.
Click to expand...

Good observation. This may be analogous to the transition from
semiconductor transistor and tube transistor in music recording. In the
60s music industry used recording instrument made of tube transistor to
record many great songs. It was fuzzy but had a warmer effect. The
digital music is said to be too "grainy", kind of like using dots to
paint, precise but grainy.

Since CRT is analog, it does not rely on physical pixels like the
LCD. But the LCD can be quite impressive when it has 120 dpi or higher,
which for 19" it is about 14" width times 120 or 14x120=1680 horizonal
pixels. But I found even 1400 pixels is acceptable for 19" LCD.

I found that .254 mm dot pixel seems to be the dot size where human
eyes can no longer distingish the dots. It is .254 mm / 25.4 mm/inch =
..01 inch per dot. A 19" LCD of 14" width should have 14/.01 = 1400
horizontal pixels. But most 19" has 1208 horizontal pixels, which is
14(inch)x25.4(mm/inch) /1208 (pixels) = .294 mm per pixel. far greater
than the threshold size of a dot. It is a designing mistake. We should
look for 1400 horizontal pixels (correspond to .254 mm dot pixel) 19
inch models.

For a typical LCD, the minimum horizontal pixel should be Width /
..01> (or times 100). The following is the minimum horizontal pixels for
various LCD:

17" 1208 pixels (12 inch width /.01)
19" 1400 pixels (14 inch width /.01)
20" 1480 pixels (14.8 inch width /.01)
20" wide screen 1600 pixels (16 inch width /.01)

Using pixels lower than this list will generate a "grainy" effect.
For example, a "/' will be made of just 5 to 6 dots instead of a tilted
line. Of course, the simplest method is to simply check that the dot
pixel is smaller than .254 mm. But most spec do not list this most
critical number. Selling 1208 pixel 19" LCD (90% of all 19" LCD) is
purely for the profit, not for the customer. The invisible hand of Adam
Smith failed terribly here.
 
chrisv said:
Most likely yes, for you. Or you could just sit further away 8), so
you can't resolve the pixel structure.
Click to expand...

I am forced to use 1024/768 resolution instead of the default
1208/1024 for my 19" LCD (.284 mm dot pixel) to read text. Now at least
I see lines instead of dots. A slash '/' is now a line rather than just
5 dots. The default fonts become bigger on screen, but at least they
are no longer "grainy" like before.

While using the native resolution of LCD performs the best when dot
pixel is smaller than .254 mm, it performs the worst for reading text
when the dot size is large than .254 mm. We can lower the resolution to
put more dots for each stroke of the letters in this case to eliminate
the "grainy" looks of the text.
 
I forgot to point out that the acceptable dot pixel (for LCD) .254 mm
is .01 inch, or 100 dots per inch (dpi). It is nowhere near the PDF
standard of 600 dpi, but good enough for a desktop monitor.
 
chrisv said:
Hmm... Well, assuming the same "dot pitch", the LCD should not be
"inferior" to the CRT in this regard. However it may appear to be
because the CRT will, in general, be less precisely focused, thus
softening the image somewhat and making it easier on the eyes.

Another possibility are differences in the gaps between the "lit"
portions of the screen. I don't know if one of these two technologies
is superior in that regard. Maybe Bob will chime in here.
Click to expand...

Be happy to - I think I've read enough of the thread at this
point to figure out what the @#$^%%^# the original poster
was complaining about...sure wasn't clear at first, though.

Yes, an LCD is a fixed-format device; it has defined pixels and
subpixels which exactly correspond to the pixels of the displayed
image, assuming the thing is being driven in its native mode. CRTs
don't have that; there's a "dot" structure to the screen of a color
CRT, but the dots in no way are constrained to line up one-for-one
with the "pixels" of the image (if an analog video signal can even
be said to have pixels in the first place...). In a CRT, the spot
size is generally a good deal larger than the pixel pitch anyway,
and is of an approximately Gaussian profile - which makes for
"softer" pixels/lines.

There's definitely a different "look" to the two technologies (or
really between the CRT and just about any of the fixed-format
types), but I'm not away of any studies which have shown that
one is necessarily "easier on the eyes" than the other. I believe
it's more a matter of personal preference. Finer pixel pitches
on the LCDs (higher resolution, in the proper sense of the
word) make for less visible dots, of course, but in the same size
screen that also means a higher "resolution" (in the sense of the
pixel format). That always costs more $$$, since the more
pixels you have, the more drivers you need, etc..

Bob M.
 
Good observation. This may be analogous to the transition from
semiconductor transistor and tube transistor in music recording. In the
60s music industry used recording instrument made of tube transistor to
record many great songs. It was fuzzy but had a warmer effect. The
digital music is said to be too "grainy", kind of like using dots to
paint, precise but grainy.
Click to expand...

Not a good analogy. The notion that digital recordings are somehow
"grainy" has been demonstrated time and time again to be nonsense.
It just doesn't hold up to any serious testing. (What really changed
in going from vinyl LPs to CDs was a loss of certain distortions
inherent in the vinyl medium, but that's a whole 'nother argument...)
Since CRT is analog, it does not rely on physical pixels like the
LCD.
Click to expand...

Technically, the LCD is an analog device as well. Most of them
happen to have a digital interface, but what happens at the pixel
level is pure analog drive.
I found that .254 mm dot pixel seems to be the dot size where human
eyes can no longer distingish the dots. It is .254 mm / 25.4 mm/inch =
.01 inch per dot. A 19" LCD of 14" width should have 14/.01 = 1400
horizontal pixels. But most 19" has 1208 horizontal pixels, which is
14(inch)x25.4(mm/inch) /1208 (pixels) = .294 mm per pixel. far greater
than the threshold size of a dot. It is a designing mistake. We should
look for 1400 horizontal pixels (correspond to .254 mm dot pixel) 19
inch models.
Click to expand...

I believe you mean 1280 pixels (the standard "SXGA" format, 1280 x
1024). But simply putting more pixels in a given screen size hasn't really
been a Good Thing in PC displays, primarily because our PCs (or rather,
their operating systems) don't really know how to deal with increased
resolution (more dots/inch). You can easily wind up with increased eye
strain, due to having characters that are too small to comfortably deal
with.

The actual threshold for spatial acuity - how well you can resolve line
pairs,
individual dots, etc. - is actually quite a bit below the point you claimed.
100 dots per inch (or pixels per inch, your call) is, at normal viewing
distances
(say, 24"), going to give you about 20 cycles (line pairs) per visual
degree. That's considered pretty good resolution, but not quite to the
limit of visual acuity. Closer to 300 ppi would be about right for that.
(Consider the difference in appearance between text displayed on a computer
monitor, and that same size text on a laser-printed page.)

Using pixels lower than this list will generate a "grainy" effect.
For example, a "/' will be made of just 5 to 6 dots instead of a tilted
line.
Click to expand...

Sorry, as things are today, most PC text will just appear smaller
(but with the same number of pixels/character) on a higher-res
screen. That IS changing, but actually understanding resolution
vs. text size certainly isn't a universal in present systems.

Bob M.
 
I am forced to use 1024/768 resolution instead of the default
1208/1024 for my 19" LCD (.284 mm dot pixel) to read text. Now at least
I see lines instead of dots. A slash '/' is now a line rather than just
5 dots. The default fonts become bigger on screen, but at least they
are no longer "grainy" like before.
Click to expand...

That's an interesting solution, considering that many would be loath
to except the image degradation that attends running an LCD panel with
non-native resolution. If it works for you, though...
While using the native resolution of LCD performs the best when dot
pixel is smaller than .254 mm, it performs the worst for reading text
when the dot size is large than .254 mm. We can lower the resolution to
put more dots for each stroke of the letters in this case to eliminate
the "grainy" looks of the text.
Click to expand...

Bring back the CRT! 8)
 
Bob said:
Be happy to - I think I've read enough of the thread at this
point to figure out what the @#$^%%^# the original poster
was complaining about...sure wasn't clear at first, though.

Yes, an LCD is a fixed-format device; it has defined pixels and
subpixels which exactly correspond to the pixels of the displayed
image, assuming the thing is being driven in its native mode. CRTs
don't have that; there's a "dot" structure to the screen of a color
CRT, but the dots in no way are constrained to line up one-for-one
with the "pixels" of the image (if an analog video signal can even
be said to have pixels in the first place...). In a CRT, the spot
size is generally a good deal larger than the pixel pitch anyway,
and is of an approximately Gaussian profile - which makes for
"softer" pixels/lines.

There's definitely a different "look" to the two technologies (or
really between the CRT and just about any of the fixed-format
types), but I'm not away of any studies which have shown that
one is necessarily "easier on the eyes" than the other. I believe
it's more a matter of personal preference. Finer pixel pitches
on the LCDs (higher resolution, in the proper sense of the
word) make for less visible dots, of course, but in the same size
screen that also means a higher "resolution" (in the sense of the
pixel format). That always costs more $$$, since the more
pixels you have, the more drivers you need, etc..

Bob M.
Click to expand...

What is the maximum display resolution or the dot pixel of the LCD
that you are using? Is that a good monitor in your opinion?
 
What is the maximum display resolution or the dot pixel of the LCD
that you are using? Is that a good monitor in your opinion?
Click to expand...

I'm not sure how this is relevant, but at the moment I'm using
a laptop PC since I'm on a business trip (in Taiwan currently,
and oddly enough visiting LCD manufacturers, which is part
of what I do for a living). This one happens to be a 12.1"
XGA (1024 x 768), which would mean a resolution of
approx. 106 ppi. When in the office, I'm currently using a
19" SXGA (1280 x 1024) monitor, which would be about
86 ppi. I'm happy with it.

By "dot pixel," do you mean "dot pitch"?

Bob M.
 
Bob said:
I'm not sure how this is relevant, but at the moment I'm using
a laptop PC since I'm on a business trip (in Taiwan currently,
and oddly enough visiting LCD manufacturers, which is part
of what I do for a living). This one happens to be a 12.1"
XGA (1024 x 768), which would mean a resolution of
approx. 106 ppi. When in the office, I'm currently using a
19" SXGA (1280 x 1024) monitor, which would be about
86 ppi. I'm happy with it.

By "dot pixel," do you mean "dot pitch"?

Bob M.
Click to expand...

Very interesting. I also use a 19" SXGA 1280x1024 LCD (a Dell
1907FP by Samsung) in my office and it is just horrible. The LCD I use
at home is a 17" SXGA 1280x1024 (Viewsonics VX700) and it is zillion
times better, none of the grainy look of the former. The difference
should be less than 19/17, but it is like night and day. One is silky
smooth and the other grainy. I start to think that it is not just the
..25mm vs .294 mm dot pitch difference, it may be due to the physical
structure of the pitch itself of different makes. One of those days I
will post pictures of comparison on the net to show the dramatic
difference (especially the visible grid) that might cause some grief
like mine.

In the mean time I probably will switch to a Viewsonics VX2025WM
20" LCD that has .26 mm dot pitch. The user rating on cnet.com is 8.8
for this monitor, comparing to a low 6.4 for the 1907FP. So that's a
good sign. I hope this one is as good as the VX700 I have at home.
Sorry to be so specific. After getting bit by something I have taken
for granted in the past, I need to be more specific to get a good
solution this time.

Thanks!
 
(e-mail address removed) wrote in @c28g2000cwb.googlegroups.com:
I just received a Dell 1907FP 19 inch LCD monitor. It has a very
visible grid matrix on the screen like a layer of nets that turns lines
into fuzzy dots. After a few hours of using it, my eyes is killing me.

I checked my previous Viewsonics VX700 17 inch LCD and there is no
such visible grid matrix on the screen. There are several possible
explanations:

1. The Dell 1907FP is using a grid matrix wire to provide current to
the pixels, the VX700 is using different technology which has less
visible grid matrix.

2. The VX700's dot pixel is only .25 mm and thus is less visible than
the 1907FP which has .294 mm dot pixel.

3. All of the above.

Anyone knows the reason why these two LCDs look so different?

(Most 19" LCD uses .294 mm dot pixels. Will a genric 20.1" LCD with
.255 mm dot pixel solve this problem?)
Click to expand...

Are you certain ClearType is enabled for font smoothing? You should not
use ClearType on a CRT, but it can be almost mandatory to remove the
grittiness of fonts on an LCD. You can then optimize the settings of
ClearType with a little freeware program, ClearTweak. Highly recommended.


--
Dennis Roark

(e-mail address removed)
Starting Points:
http://sio.midco.net/denro/www
 
I've found that ClearType can be useful in rendering text on CRT
displays up to a point, though the effect is more subtle than on a
LCD. Another factor I've found annoying in LCD displays, especially
in the last few years, is the grainy anti-glare coating so often
used. It looks like I'm viewing the display through a sandstorm and
it's very hard to tune out.
 
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