The NEC LaVie
MX notebook, with its Crusoe TM5600 processor, recently caused a hefty drop
in the value of Transmeta's stock after news that 284 notebooks were
being recalled due to a glitch when reinstalling the OS. Now that the dust has
settled a bit, its time for a closer look at a few of the technologies that
make the LaVie MX one notebook to watch closely.
While the integration
of the Crusoe processor would bring our attention to this notebook
regardless, it is actually the screen that makes this notebook stand out among Crusoe-powered portables.
You see, the NEC LaVie MX has no back light behind its' 10.4" Reflective
TFT LCD screen.
The trade-off is that while the LaVie's screen is easy to see under
bright light, it not so easy to see under low lighting conditions. Of course
this arrangement does translate into huge power savings, giving the LaVie upto 11
hours of usage. This is an unprecedented amount of time for a notebook
running the Windows environment, but is it worthwhile? We've all heard
about how a laptop's back light consumes a tremendous amount of battery
life... so why haven't many notebook manufacturers taken out the
Three LCD Screen illumination Technologies:
The main reasons lie with
colour quality and resolution. Reflective LCD display technology is still a
relatively young technology, and at present there are three main adaptations underway, each with their
own benefits and problems. The three technologies are: Reflective LCD, Transflective LCD,
and Transmissive LCD.
Since the LaVie MX uses a reflective LCD screen we'll start
off with this variant. Reflective LCD technology makes use of only the
surrounding ambient light to illuminate the display. Beneath the surface of the
display a rear polarizer is combined with a reflector assembly to
bounce back ambient light. From our experience with one of the LaVie
notebooks on display at COMDEX, the technology only works well in fairly bright
light only. The colours are little different from what you might normally be used to,
but the display is clear and readable so long as the
text is highly contrasted. [Typically Reflective LCD screens are easiest to read about 5,000 LUX
of ambient light and have a power consumption of 0.5W to 1.0W
for 10-12" sizes.]
Transmissive LCD display technology is essentially how a normal display operates. To view the
screen the back light must be on continuously, and brighter then the
ambient light or it will be washed out and difficult to read. These displays are
naturally very power hungry and operate best in darker lighting conditions (under
5,000 LUX ambient).
Finally, Transflective LCD technology is a combination of Reflective
and Transmissive types. The rear of the LCD's polarizer is partially
reflective and combined with a back light for use in all types of lighting
conditions. The benefit here is the back light can be left on where there is
insufficient outside lighting. Conversely when there is enough ambient
light it can shut off to conserve power. Transflective takes the best of both
worlds and enables viewing in dark environments. Additionally the
display won't "wash out" when viewed in direct sunlight. However the
contrast rating is not as high as a purely Transmissive display.
All in all the Transflective technology would seem to be the best
combination of technologies. We did see some examples of this type of screen at
COMDEX 2000 but were unable to see how they faired in sunlight.