Technology
Asymptotes…
Recently, I read an article about an exploratory effort in Japan
by NHK to develop a new higher resolution television system. The
NHK Super Hi-Vision system is designed to deliver images with 8K
x 4K resolution with a 16:9 aspect ratio. As explained in
the article, the objective is to be able to have a 100-inch display
and not have the individual pixels be visible from a distance of
one meter. Wow! Will we really be able to appreciate
such spectacular images given that the current HDTV system is already
better than the practical resolution of film images we have become
so accustomed to seeing in movie theaters? Pondering
this led me to contemplate the broader question of whether there
are limits when we no longer have the need or desire to push for
further improvements – or perhaps the product is already
so good for its intended purpose that we will not pay for anything
better.
Perhaps we can gain a useful insight or two by taking a look at
what has happened in other technology areas? Film cameras
reached their practical limits of resolution many years ago. Some
of the lenses from the 1930s and 1940s achieved resolution levels
as good as anything that is available from “modern” optics. Instead
of pushing for further refinements in resolution, lens designers
found a more receptive market for added features such as variable
focal lengths (wide angle and telephoto “zoom” lenses),
larger apertures, and auto-focus. In trying to balance between
versatility and resolution, it was not uncommon to actually have
the resolution get sacrificed to some degree. The camera
makers learned where the optimum balance was between film resolution,
lens versatility, and manufacturing cost. That led to many
years of products being introduced that continued to be improved
in many aspects, but lens resolution was not one of them. Thus,
today, most images taken with professional quality 35-mm film cameras
fall short of the equivalent of HDTV resolution. For those
professional photographers who need to produce higher quality photographs
for use in glossy magazines or for art gallery displays, a niche
market developed using larger film formats such as 2 ¼ square
or 6x7 cm. A technology asymptote was achieved and
sustained for many decades.
Let’s now look at a more recent but closely related example. Some
years ago I wrote a column predicting that two megapixel imagers
would be sufficient for digital cameras since they would produce
images of comparable quality to 35-mm film. Clearly, I was
too conservative in my prediction. To get to the 2 megapixel
number, I was trying to balance what I estimated to be acceptable
picture quality with the capacity of storage devices available
at that time. I did not anticipate that the camera makers
would get into a “horsepower” race to see who could
introduce a camera with the next higher megapixel number. Fortunately,
the cost of storage continued its rapid drop so that the huge image
files that resulted from the 5 – 10 megapixel imagers are
no longer all that difficult to manage. But the pixel count
race is also finally reaching its technology asymptote. We
seem to be settling on 10 megapixels as the magic number for “good
enough”. That is sensible since the lenses that are
sold with those cameras are marginally adequate to fully utilize
even this image resolution.
In other areas of electronics, we have seen similar technology
asymptotes come to pass – often with frustrating results
for product manufacturers and resellers. Consider, for example,
the market for audio components. Audio signal reproduction
has become so precise and distortion free that it is no longer
possible to hear the difference between many of the system components
such as amplifiers, tuners, and CD players. Speakers, as
electromechanical devices, have not yet been able to achieve such
perfection, but the end result has been that about the only way
to distinguish products is on their styling, audio power output,
and price. Since we can no longer hear the difference, and
because profit margins on these components are now so small, many
resellers have adopted shady practices to increase profits – such
as selling connecting cables and speaker wire at exorbitantly inflated
prices with the claim that these accessories will bring out the “full
audio capabilities” of the system.
In the mid-eighties, we were introduced to the first personal
computers. The IBM PC and the Apple II gave us our first
glimpse into a future that would soon be upon us. The IBM
PC and it’s clones had a clock speed in the vicinity of 10
MHz and a hard disk that could store about 20 Megabytes. Not
so many years after that, we were introduced to desktop computers
with 100 MHz clock speed, then 500 MHz, and then the magic 1 GHz
number was achieved. There were plenty of predictions
for when we would see 10 GHz clock speeds and beyond. Having
started my career as a microwave engineer, I knew how difficult
life can get as one tries to work with signals in the many GHz
range. Well, sure enough we made it to about 3 or 4 GHz and
then life got really difficult – we hit the wall. The
speed race ended and we were forced to switch over to multi-core
processors to continue to increase computational capabilities. Now
the race is on to see who can introduce the next highest number
of cores. And in fact, we never even achieved the 3 or 4
GHz operation. That speed is only for the arithmetic unit
within the core of the processor. The information that is
swapped in and out of memory is typically at speeds of well under
1 GHz. So again we have approached and reached a technology
asymptote.
It seems that with every product and every technology there comes
a time of either “good enough” or that further increases
are so difficult and/or so expensive to achieve -- or are of such
marginal benefit -- that it is commercially prudent to develop
other interesting capabilities instead. I would suggest
that we have come to such a time in the capabilities of desktop
and laptop computers. For a number of years now, we have
been stagnant in our use of personal computers as word processors,
spreadsheet manipulators, and for the preparation of presentations. What
has evolved instead is that we are now using our computers more
as communication and storage devices. That would lead one
to conclude that Windows is a mature product of limited future
usefulness. So why is it still growing and producing major
profits for Microsoft? It appears that along with the concept
of technology asymptotes, we also need to explore the concept of “technology
momentum”. We will do that in more detail in next month’s
column. Specifically, we will look at what keeps technologies
going even after they seem to have lost their predominant position
and why new entrants find it so difficult to unseat an incumbent
technology.
To return to our own field of display technology, can we say when
we will have achieved the technology asymptote for display resolution? Are
we really going to be watching 4K x 8K displays in our living rooms
anytime soon? Even NHK admits that their effort is for the
long term. Since it took about 30 years to develop
and implement the current HDTV standard, they are similarly thinking
long term -- several decades out. But other than for
special entertainment applications there is no assurance that we
will ever see such high-resolution displays in our homes – even
in 30 years. We may find it more interesting to add other
features and leave the resolution about where it is with HDTV. We
may have already reached the technology asymptote for display resolution.
Are we there yet? Is 1080x1920 resolution with 256 levels
of gray for each color the final frontier for home entertainment? If
you don’t agree, then where do your think it is? I
welcome your comments on this topic or others.
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