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Re: Inexpensive Display Technology

Tony Havelka wrote:
> 
> -----Original Message-----
> From:   R. Paul McCarty [SMTP:]
> Sent:   Monday, April 27, 1998 8:41 AM
> Subject:        Re: Inexpensive Display Technology
> 
> > This is really depressing to see the interest in wearables, and have no
> > really *good* display for people to use.  I would suggest the M1 from
> > Liquid Image, but it uses quite a bit of power and I think $1000 is a
> > bit more than most people want to spend on a display.
> 
> Paul,
> 
> Thanks for the plug!  We feel that at ~2.5W, the M1 consumes very little
> power given its functionality:
> 
> It handles both VGA and NTSC on the fly with no need for signal converters.

I don't think NTSC and VGA is very useful to someone building a wearable
comptuter, you either use one or the other.

> It accepts a wide variety of voltage levels (6.5V-24V) in order to
> accommodate almost every existing platform and design with out expensive
> modifications to the electronics.

Save the one everyone is building around; PC/104 which runs at 5v. 

> It also has brightness and contrast controls so that you can modulate the
> power consumption manually.  i.e..  The brighter it is the more power it
> consumes.

>From what I've read most of the power consumed by the M1 is in the
driver electronics since the display itself is rated at something like
20mw. So the brightness contrast controls wouldn't save you more than
20mw.

> > It's hard to believe that there was better hardware for wearables
> available a couple
> > of years ago, then there is now.

I figured this would be misinterpreted, what I was refering to was the
P4 private eye that is used in the lizzy spec, and is not available
anymore, and support for the P5 is still forthcomming.  There's nothing
equivalent to this out there` right now.

> > Nothing exists like this in this price range other than wraparound VR
> > glasses, which aren't really suitable for walking around with, or a
> > video display from a camcorder, etc., but there is some concern that the
> > NTSC signal doesn't render text very well.
> 
> If you design software to run on an NTSC based system it will look great.
>  WebTV is a prime example.

But WebTV runs on 21" monitors, not displays the size of your pinkey
finger.

> Designed for an NTSC signal, it utilizes larger
> text and proper layout to achieve a pleasing result. 

Okay, I agree with this, if you can generate 40 columns (instead of 80)
you can get a useable commandline prompt on an ntsc display, so this is
probably a good option for a HUD, but there seems to be a general
lethargy about going this route with a small crt, or ntsc lcd (except
for Steve Mann. ;) There may be reasons why people are holding out for
other technologies rather than trying this. Maybe its just not very
appealing to strap a crt/lcd display ripped out of an old camcorder.
Maybe its just too much in the way of electronic tinkering for some
people.<shrug>

All I know is from all the posts it seems pretty clear that there are
dozens of people on this list who want to build a wearable, but are
getting stuck on the display. 

-Paul
-- 
R. Paul McCarty / DARS Coordinator /  / x52059
317 Lattimore Hall, University of Rochester, Rochester, NY 14627
Computers don't make mistakes;what they do,they do on purpose.-Dale/KOTH

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