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FROM THE BENCH

E-mail: fromthebench@gcmagazine.co.uk

Alan Bennett reviews the rapid development of thin screen technology approach the standards set by Pioneer

manufacturers and developments

(now out of the TV business) and adopted

such as 3D imaging have led to the most

by Panasonic, an excellent example of

intensive research and development:

which is the new LG PK range. Here the

compare a new current screen, LCD or

very narrow (‘razor’) bezels give a real

plasma, to its counterpart of two or three

picture-frame effect; hopefully there will

years ago and the progress is obvious.

be no physical repercussions from this as

which shutter each eye in turn to give two

happened elsewhere with a lighter LCD

separate images and the 3D effect. The TV

model in which flexing of the display panel

transmissions, decoded in the receiver,

could lead to failure.

provide the two images; thenceforth the

LCD Backlight technologies continue to improve, with LED arrays becoming better and

Still there is no real solution to the risk

SHARP QUADPIXEL TV WITH YELLOW SUBPIXELS

signal processing and screen structure is

cheaper. Side-lighting makes for very thin

of phosphor-burn in plasma panels, in

up to the setmaker, balancing (as ever!)

panels, while full-field LED lighting, by local

spite of manufacturers’ claims: moving the

performance against cost, and trying to

dimming and by colour matrixing, improves

image about just blurs the edges of any

second-guess the punters’ preferences.

contrast ratio and colour rendering

burn, while ‘washing’ and ‘wiping’ systems

The high initial price of 3D screens will

respectively. All LED backlights use much

inevitably come down, depending largely

less energy than fluorescent ones. The

have minimal effect, I’ve found. When the problem is really solved set makers will

latest advance to come onto retailers’

stop excluding screen burn from their

feeling is that 3D will not become a mass-

shelves is the incorporation – by Sharp in

guarantees!

market product.

their QuadPixel models – of a fourth sub-

The reflectivity of the glassy surface of

on the take-up of this new feature. My own

One spin-off from this technology which

pixel colour, yellow. In normal TV displays

the plasma panel can dilute the contrast

yellow is produced by a combination of

and be distractive in a well-lit room. Look

I think could do very well indeed is a dual picture TV screen, on which two totally

red and green light, be it from phosphors

at the screen surface with the set switched

different images could be simultaneously

in plasma panels or filters in LCD ones. The

off. LCDs are very black while plasmas can

displayed, depending on the viewing angle.

gamut of colour this offers in LCD displays

be lighter, and reproduced image-black

This would solve, once and for all, a huge

is not as good as that of a dedicated yellow

can only be as dark as the un-energised

conflict in the average living room, and is

filter, with which gold and similar colours

screen, relevant in any viewing situation

perfectly feasible, though the sound is less

look better. It is important to remember,

short of total blackout. Think of reflective

easily dispensed! One programme would

however, that the range of colours in a

cinema screens and the old cathode ray

have to be via the speakers, the other by

broadcast picture is limited to some degree,

tubes which got better and better as they

headphones. No more fighting over the

and a chain is only as good as its weakest

got darker and darker over the years.

zapper, no more kitchen-viewing of Corrie

link. Some local picture sources (PC, game,

Plasma does best in dark surroundings and

when the football’s on ... I could sell a lot

AVC-HD) can be better.

without the fixed picture structures and

of them and cement marital harmony with

icons incorporated into some games and in

every one. Two and a half grand a pop?

computer displays.

No problem.

down to the digital processing engine as to

3D screens

Test cards

the screen itself, though the latter has to be

The new Sky 3D transmissions lend

I wish one of the broadcasters would

‘fast’ enough to do it justice.

themselves to two types of display. The

transmit an always-on test card. A

simplest for the viewer uses passive

stationary picture like this takes up zilch

spectacles with opposing polarities for each

bandwidth, and the tantalisingly brief

Plasma sales continue to wane in the face

eye, and a screen with a light-polarising

broadcasts of it on BBC HD show up

of competition from LCD, at least from

layer which matches the L/R images to

many aspects of TV display, particularly

where I’m sitting. Our plasma customers

them. The alternative (and better, I believe)

definition. With digital TV a stationary

now tend to be home cinema enthusiasts

is a sequential system in which left and

image does not tell the whole story, so

and TV perfectionists. These screens

right images progressively alternate on the

moving ones to check for lip-sync and

continue to improve in terms of black-

screen in very fast sequence; synchronised

motion artefacts could be incorporated

level reproduction, with some mainstream

to these are the active viewing glasses

– or given a separate slot?

Faster image-refresh rates are demonstrably improving motion rendition in terms of smoothness; this is as much

Plasma

JULY 2010

manufacturers’ products starting to

is very rapid. Competition between

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he evolution of TV screen technology

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Get Connected: July 2010  

Get Connected: The Magazine of the Electrical Industry. July 2010 issue.

Get Connected: July 2010  

Get Connected: The Magazine of the Electrical Industry. July 2010 issue.