64 TheEconomistJanuary 30th 2021
1O
ver thedecades since its invention,
the goggle box has been transformed
almost beyond recognition. What was once
a bulky cabinet sitting in the corner of the
living room has grown like Topsy in height
and width and shrunk like Ant-Man in
depth. The picture itself, once a blurry
black-and-white image composed of scan-
ning lines visible to the eye, is now a pin-
sharp display presented in a spectrum of
hues so rich than even Van Gogh would not
have balked at using them. It takes only a
slight stretch of the imagination to view
tvs as objects more like oil paintings, bet-
ter suited to hanging on a wall than sitting
on the floor. And that, increasingly, is
where they do hang.
Yet as good as televisions have become,
they are about to get yet better. Rival mak-
ers of the two types of screen technology,
one, called led, based on liquid crystals
and inorganic light-emitting diodes, the
other, called oled, on organic light-emit-
ting diodes with no liquid crystals in-
volved, are beautifying their offerings tothe point where they are more dazzling
than Lady Gaga. tvs of the future will have
yet brighter images with yet higher con-
trast. Their screens will be bendable and
may even become transparent.Alphabet soup
All of this is driven by intense competition.
At the cheap end of the market, most televi-
sion-makers offer customers both leds
and oleds. But at the top of their ranges
they have become specialists. Samsung, a
South Korean firm that is the world’s big-
gest television-maker, and tclElectronics,
a giant Chinese group, focus on ledmod-
els. By contrast lg, another South Korean
electronics outfit, devotes its upmarket ef-
forts to oled. These three firms now dom-
inate the provision of television sets, joint-ly accounting for more than 40% of global
sales, according to ihsMarkit, a research
firm. And they are deadly rivals.
Despite their similar acronyms, led
sets and oledsets work in substantially
different ways. Indeed, the term ledis a bit
of a misnomer for the former. The crucial
parts of the screen are actually the liquid
crystals. These are tiny, electronically ma-
nipulated shutters that permit or prevent
the passage of light. Individual picture ele-
ments, known as pixels, consist of a trio of
these shutters, each masking a filter that
passes light of one of the primary colours,
red, green or blue. Behind all this parapher-
nalia is a strong white backlight which is,
indeed, generated these days by light-emit-
ting diodes, but which was once the pro-
duct of fluorescent bulbs. A pixel’s hue in
an ledset is determined by how open or
closed each of its shutters is, and thus what
mixture of primaries gets through them.
An oled tv, by contrast, has no back-
light. Its pixels are made of organic materi-
als that emit light when stimulated by an
electric current. Different materials emit
different frequencies, so different colours
can be mixed in this way.
There is also one other difference.
When an oled pixel is switched off, it re-
laxes to a deep, dark black. Even when
closed, however, the shutters of an ledsys-
tem permit some of the backlight to sneak
through. The result is not so much black as
grey, which reduces the contrast betweenCompetition and innovationTV’s tech wars
Television-makers are pitting rival technologies against each other. Customers
will see better pictures on their screens as a resultScience & technology
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