Great Human Technology, INC.
Introduction to Monitor & Flat Panel Display Technology
In today’s business environment, high quality monitors have gone from being a luxury to a necessity.
With employees and self-employed professionals spending the majority of their days working with
their computer and monitor, it is more important than ever to purchase a quality monitor that will
provide crisp, bright images, while reducing the strain on your eyes. This section will explain some of
the terms and technology you should know when purchasing a monitor.
Technical Tour - simple, narrative explanation of Hitachi’s monitor technology CRT Monitor
Overview - explanation of terms you’ll need when purchasing a monitor

Shadow Mask vs. Aperture Grill Technology

Screen Size

How Hitachi Monitors Work

The Importance of Resolution

Dot Pitch

Refresh Rates

ErgoFlat vs. Flat, Square

ErgoFlat White Paper
Shadow Mask vs. Aperture Grill: There are two main types of CRT (Cathode Ray Tube -- the
traditional monitor) technologies available. The first is Invar Shadow Mask Technology and the second
is Aperture Grill technology. In the simplest terms, the Invar Shadow Mask is a heat resistant metal
sheet with holes punched into it to allow the light to pass through. The Aperture Grill models use
vertical lines of light to compose their image. On the right, you will see a comparison of Hitachi’s
Shadow Mask technology and an aperture grill model. The Shadow Mask creates a more precise, crisp
image than the aperture grill model because of the special design. In addition, the aperture grill model
is held together by two thin wires called "damper wires" that can frequently be visible across your
screen and image.
Screen Size: The screen size is measured diagonally from corner to corner. Please note that the CRT
size is not the screen size. Most monitors will list "viewable image size" which does not include the
bezel and is the actual viewing size for the monitor if it features edge-to-edge imaging.
How Hitachi monitors work: The simple version of this explanation is that inside the monitor casing
there is a Cathode Ray Tube (CRT). The CRT has an electron gun assembly that fires electron beams
that the mask shields and directs into specific phosphors that glow and illuminate the image. Many
Hitachi monitors use a new PrecisionFocusTM technology that provides an additional focus mechanism
that ensures, crisper, brighter images that are 10% sharper than the previous state of the art. In addition,
Hitachi uses Invar Shadow Mask technology that is composed of a special heat resistant alloy which
resists the warping that some shadow mask monitors may experience.
The importance of resolution: Resolution is the number of horizontal dots multiplied by the number
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of vertical dots (pixels). Resolution (the density of the screen image) tells the consumer how much
information can be displayed on the screen.
Dot Pitch: Dot pitch is the diagonal distance between two phosphors of the same color. The smaller
the dot pitch, the better the image - images will look crisper and edges will appear smoother. Dot pitch
is a KEY element to consider when purchasing a monitor. Most Hitachi monitors have a .22mm
horizontal dot pitch and a vertical dot pitch ranging from .13mm - .16mm vertical - one of the lowest
dot pitches available to ensure, crisp details - even at the edges.
Refresh Rates: Refresh rates indicate the speed at which a screen is refreshed or re-drawn. The higher
the refresh rate, the less "flicker" a user will encounter. Anything above 75 Hz for the monitor’s prime
resolution setting is considered VESA standard - a rating system that enables a monitor vendor to use
the "flicker-free" logo. The refresh rates decline at higher resolutions because the number of pixels the
monitor must refresh increases, slowing down the refresh speed. Consumers should check the refresh
rate at various resolutions. This is also a KEY factor in selecting a monitor because "flicker" is one of
the main causes of eyestrain. For example, Hitachi’s popular SuperScan 751 has a prime setting over
100 Hz. -- well above the standard 75 Hz. flicker-free refresh rate plus all settings -- even up to
1600x1200 are at or above 75Hz.
ErgoFlat vs. Flat, Square: Ergo Flat is Hitachi's brand name for its flat-faced monitor and what many
call "Perfectly flat". Flat, Square is an industry standard term used since 1997 indicating minimal
curvature (but still a curvature) of the monitor tube. Flat, Square is not flat-faced like an ErgoFlat.
There are benefits to both technologies at this time. Flat-faced monitors from all manufactureers have
some advantages & drawbacks. On the plus side, they have much less glare than the Flat, Square (FS)
& images have a flater, more realistic appearance. Some common problems with competitive flat-faced
monitors range from low brightness and poor performance at the edges and corners to convergence and
beam landing issues. Hitachi overcomes these issues by using special glass with a 44% transmission
rate(most aperture grille models have 38 - 41% transmission rate) for improved brightness and contrast.
In addition, because of Hitachi's Invar shadow mask tube, our flat-face model does not require the
multiple circuitry controls used by aperture grille models to prevent heat warping, as our new shadow
mask has a 25G minimum strength rating. Still many critics feel flat, square monitors may have an
edge in sharpness and geometry, as well as a price that is more accessible for most consumers. Below is
a picture of the side of both an Ergo Flat and Flat, Square monitor so you can visually see the
difference and decide which meets your needs.
Ergo Flat
Flat, Square
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Below are Explanations of the icons you will find on the Hitachi brochures. Some represent
accreditation for meeting specific standards.
Many Hitachi monitors utilize Hitachi's revolutionary PrecisionFocus™ technology
with multi-step dynamic focus and auto astigmatism correction. Displays are
significantly sharper than the previous state-of-the-art and deliver brighter, richer color and improved
contrast at the same time.
Many Hitachi monitors have a 0.22 mm horizontal dot pitch which is one of the
sharpest dot pitches - and the sharpest image - you can buy. This enables the monitor to
display finer detail which makes for clearer, crisper graphics and improved readability, even of very
small text. It also enables Hitachi monitors to genuinely resolve the high resolutions needed for
document imaging, desktop publishing and CAD applications.
Hitachi's Elliptical Aperture Dynamic Focus (EA-DF) electron gun uses an advanced
focus system to dynamically - adjust focal length while the beam is scanning, and at the
same time control the cross sectional shape of the beam. The result: uniform brightness and sharpness
with exceptionally low distortion, even in screen corners.
A high refresh rate can eliminate screen flicker and reduce eye fatigue. The Video
Electronics Standards Association recommends a refresh rate of 75 Hz or more. So
make sure your monitor and your graphics controller support 75 Hz at your planned resolution. Your
eyes will thank you.
Monitors with the Hitachi True-color control system let you adjust screen colors to
closely match printed output.These monitors even let you control white balance (color
temperature) to approximate the whiteness of a sheet of paper, or "computer graphics white" in a video
presentation.
All Hitachi monitors are now both PC and Mac compatible. Mac adapters are available for
free (with proof of purchase) via Hitachi customer relations and are mailed to you upon
request.
Hitachi displays give you full edge-to edge viewing. No black border around the edge
of the screen.
On-screen control makes monitor adjustments quick and easy. Operation is intuitive
and control is exceptionally flexible. Many monitors enable users to control annoying
moire patterns and provide comprehensive geometry adjustment including left and
right side pincushion and trapezoid controls. Our newest monitors display control menus in any of five
languages.
Hitachi monitors are compatible with a variety of plug and play standards including
Windows 95/98 and DDC 1/ 2B. This means they automatically configure themselves
to the resolution and refresh rate that best matches the capability of your computer
system's graphics controller. So all you do is plug them in. Installation and setup couldn't be easier.
Many Hitachi monitors have been tested by Microsoft to make sure they work well
with Windows 95/98 and take advantage of Windows 95/98 features.
Hitachi monitors are equipped with an automatic power management feature that saves
energy and prolongs tube life. The feature is designed to EPA Energy Star, VESA
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DPMS and other specifications.
Hitachi's 3-year limited warranty gives you, complete peace of mind. It covers all labor, all
parts, even the tube, for the full 3-year period.
Technical Tour
Why no other monitor comes closer to reality
Imagine we are inside your monitor looking at the backside of your computer screen. If you look at the
magnifying glass to the right the small dots you see are called phosphors - the technology that creates the
images on your monitor screen.
What makes our monitors produce better images?
One of the differences that make Hitachi monitors so unique is the way
we arrange our phosphors. If you look carefully at the screen of a Hitachi
monitor, you will see clearer, crisper images - even at the edges and
corners where other monitors tend to become fuzzy. In addition, the color
will look more vivid with superior focus and clarity. We do this by using
Shadow Mask technology. If you look to the right, you will see the layout
of a Shadow Mask and Aperture Grill.
The drawing on the left shows the aperture grill, which is how some other monitor manufacturers
achieve color images. The picture on the right is Hitachi’s shadow mask technology with our famous
dot trio rounded phosphor dots. We at Hitachi feel that the Invar shadow mask technology we utilize
provides better color purity that is more stable and dependable than aperture grill. Furthermore,
aperture grill monitors contain two support wires (called damper wires) that hold the vertical lines
together. These two damper wires are frequently visible as lines running across your screen and images,
providing a distracting image distortion. With Hitachi’s Invar shadow mask - you will never see these
lines distorting your screen images.
By using Invar shadow mask technology, a high precision
element that keeps the electrons from hitting the wrong
phosphor dots, Hitachi monitors provide greater color purity
than other monitors. By using a special metal with a very low
expansion
rate
called
Invar,
Hitachi
eliminates
the
displacement distortions that some monitors (usually the lower
quality, less expensive ones) face when their shadow masks
heat up and warp slightly.
Why our dot pitch produces better pictures
The thing that makes our images so crisp and our colors so real is our Enhanced Dot Pitch (EDP),
which we use on all our latest monitors. In the drawings to the right, you see magnified images of the
dot phosphors that compose the images on your Hitachi monitor. The dot pitch is the distance between
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the adjacent red/green/blue phosphor groups. To simplify things, with any monitor, the smaller the
dot pitch, the sharper the images will be. When looking at Hitachi’s EDP dot configurations, at the
right, please notice that the horizontal and vertical resolutions are more uniform and the dots are larger.
This combination provides several important advantages. First, this creates a larger phosphor area,
which creates higher maximum brightness and better control of brightness and contrast. Second, the
uniformity of resolution makes small text more legible. Finally, the larger dots give you an increased
color purity margin, which is why images and text are clearer on a Hitachi monitor.
Superior Focus
Hitachi monitors use either our proprietary A-EDF (Advanced Elliptical Aperture, Dynamic Focus) or
our proprietary PrecisionFocusTM electron gun technology. These guns automatically adjust the focal
length while the beam is scanning. In addition, it also
controls the cross sectional shape of the beam. This
ensure crisp, clear images both mid-screen and in the
corners.
In
technology
addition,
is
10%
Hitachi’s
sharper
PrecisionFocusTM
than
the
previous
state-of-the art. By inserting two additional focus lenses
and improving the beam size, the PrecisionFocus TM technology available on many of Hitachi’s
monitors provides an even higher level of brightness and clarity.
Comfort
Every Hitachi monitor is carefully designed to meet or exceed rigid safety and ergonomic standards. So,
you can be confident that the one you buy will fully comply with important electrical and mechanical
safety standards, low radiation, and flicker-free images. In fact you’ll find that the way we eliminate
flicker is a big reason why user comfort is a major Hitachi advantage. If you look at the specifications
on Hitachi’s monitors, you will notice that the refresh rates are all VESA standard (75 Hz) and above even at high resolutions. This means that you will have a rock solid image without annoying flicker which is frequently linked to eyestrain and headaches. In the final analysis, Hitachi monitors combine
the quality and comfort critical for the long hours people spend viewing their monitors. You don’t have
to take our word for it. We encourage you to visit the "Reviews" section of this site that features awards
and reviews that Hitachi monitors have received. Thank you for taking the time to get to know Hitachi
monitors and we hope this technical tour has been helpful in understanding our products. For further
information we encourage you to call or email our Customer Relations department (information
available in the "Contact" portion of our site) and one of our representatives will be happy to provide
additional information and assistance.
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