This little CRT video monitor from JVC is no ordinary thing.
While it may look like an unassuming, and quite dainty, professional video product,
it’s actually quite remarkable.
If you know a thing or two about color CRT televisions and monitors, you might be a little surprised
when you get up close and personal with it.
See, you won’t find any phosphor dots or stripes on this display.
Nu-uh.
That’s because this monitor is actually black and white.
Let me show you.
If I do a little… unauthorized disassembly, you’ll find the face of the picture tube
staring at you clear as day.
If I pump some video into it you’ll discover the picture tube is in fact
a black and white picture tube.
We can see the video scan-lines created as the electron beam sweeps across the tube
clear as day. (yes, the same expression was used twice. Deal with it.)
And, of course, everything looks either black, white, or some sort of grey in between.
But, just by placing this little cover in front of the CRT, it becomes a color image.
And a pretty good one, too.
This is some freaky stuff man!
Color,
black and white,
color,
black and white!
I could do this all day… but instead let’s explain what’s going on here.
This monitor is using a technology which JVC liked to call LCCS, for
Liquid Crystal Color Shutter.
See, this cover isn’t just there for style points.
In fact, it creates the color image in conjunction with the picture tube.
You might be familiar with the active shutter technology used in some 3D glasses.
These glasses have liquid crystal shutters in each eye
which alternately block your left eye and then your right from seeing what's in front of you.
If you coordinate that with a high-refresh rate display that can switch
back and forth in tandem with the glasses, then you’ll see a stereoscopic image.
This shutter, though, is a little different.
Rather than blocking all light, it can select between three color filters to tint the image
either red, green, or blue.
If it does that fast enough, you won’t be able to notice.
And, so long as the color-switching is carefully coordinated with what the CRT is doing, you
can create a color image by first drawing a red image,
then a green one, and then a blue one.
So long as the color shutter can match itself up with the sequential images from the CRT,
it will appear as a full-color image.
Now aside from just being… well nifty, this little bit of tech has some surprising similarities
both to a modern technology and a much, much older technology pushed by CBS.
Let’s start with the newer tech, first.
DLP projectors (and not long ago, televisions) typically use a very similar system to create
a color image.
See, on its own, DLP technology
(which stands for Digital Light Processing)
can’t produce color.
DLP works by shining a bright light source onto a DLP chip,
known as a Digital Micro-mirror Device, or DMD.
Microscopic mirrors on its surface can reflect light in either one direction or another as
a voltage applied to them causes them to pivot.
In practice these mirrors become pixels, and if you want the pixel to be white, you align
the mirror so that if reflects light from the light source out through the lens and
onto the screen.
If you want the pixel to be black, you tilt the mirror the other way, and light is instead
reflected onto a black surface inside the projector which absorbs that light.
Although the mirrors have only a binary state, either on or off, you can create shades of
grey by dithering them, or moving them back and forth really really quickly.
But, you may have noticed, that there’s no color component here.
Very expensive DLP projectors, like those used in cinemas, will have three DLP chips,
one for each color component of the RGB space, but most consumer models will use one DLP chip,
and place a color wheel in between the lens and the chip.
The color wheel is made of sections of dichroic glass and can produce extremely pure red,
green, and blue light.
Sometimes there’s a white section, too, to increase overall image brightness.
When the projector (or rear-projection television) is operating, the color wheel spins very quickly
to color the output from the DLP chip red, green, and blue over and over again.
And, since the DLP chip is wicked fast, you can create a full color image simply by drawing
three monochrome images in sequence,
so long as you do it fast enough for persistence of vision to kick in.
This is what causes the rainbow effect you may have seen when looking at a projection
screen or certain televisions.
When you move your eyes quickly, you’ll see that bright objects break apart into a
streak of red green and blue.
This is particularly noticeable during credits sequences.
The only way to prevent this is to use three DLP chips together, and since that’s pretty
expensive, you’ll see the rainbow effect fairly frequently.
And, to make the matter even more complex, some people are more sensitive to it than
others, and in fact some people may never notice it at all.
It may not surprise you, then, that the rainbow effect is in fact visible on this little television.
I don’t know if I’ll be able to replicate this on camera well enough, but hopefully I can.
What I know I can do is take a slow motion shot of this screen with my phone.
Now, fair warning, this is extremely flickery, so if that sort of thing may cause problems
for you, please look away until I say “persnickety”
I don’t *yet* have a high-speed camera which can capture this at a higher frame rate,
but you can at least tell that the entire screen
is being colored red, green, and blue, in rapid succession.
Unfortunately, the nature of the camera’s rolling shutter,
combined with the way CRTs are scanned, makes this kind of…
suck but I think you get the idea.
In fact, keen eyes may notice that the color shutter is actually in three sections so it
can follow the path of the electron beam as it scans the tube.
Persnickety.
Now let’s talk about that CBS thing I mentioned before.
I’ve covered this in some earlier videos of mine, so I’ll be brief, but in the early
days of color television, there were two competing systems.
CBS wanted to use conventional black and white picture tubes that would be scanned three
times in rapid succession, and a spinning color wheel would sit in front of the tube.
Really, it’s just a scaled-up version of the color wheel in a DLP projector.
Their system worked really well, and was a pretty cheap way to make color television work.
But, while building color television sets (and even cameras) like this would be very
easy, this new color television signal would be entirely incompatible with the existing
black-and-white signals, and thus existing black-and-white television sets.
RCA managed to win this fight by fudging the black and white signal and merging a color
signal into it using weird math and stuff, thereby creating what they called "compatible color".
These televisions required entirely new picture tube technology, and the cameras were literally
three cameras in one, but since these new color signals could still be received by black
and white televisions, it made the transition seamless.
So, in a weird way, this monitor is harkening back to the days of the color television wars.
It’s using a more modern equivalent of the CBS color wheel system, but it’s the exact
same principle.
Now, you may have realized that in order to do this, the television has to do some interesting
processing wizardry.
It has to take normal NTSC or PAL analog video signals, and break them up into three distinct images,
then draw them sequentially.
It can’t just draw them at the same time with three separate electron beams,
like all other televisions do.
And that probably explains why this technology didn’t appear in televisions
until the year 2000, when this was released.
It was some pretty expensive stuff.
Not the actual picture tube or even the color shutter, mind you, but the electronics required
to turn a normal television signal into a sequentially-drawn image.
In fact this itty-bitty monitor sold for about $1,200.
Yikes!
But, it did have some serious advantages.
I’ve shown you this little television before, it uses conventional dot-mask CRT technology.
The image on the LCCS monitor is night-and-day better.
Small, color CRTs tend to just… not be very good, so using a black-and-white tube and
a liquid crystal color shutter provided a significant improvement.
But the real selling point for this tech was that the screen was much easier to see in
bright conditions.
The color shutter improved contrast quite a bit, so one potential use for this monitor
would be on-location shoots for things like newscasts or even movie production.
Bright light around the screen wouldn’t make it difficult to see,
in fact it's claimed it could be seen in direct sunlight.
That said, there are some disadvantages, too.
The color is just…
OK.
It seemed fairly washed out to me, and I needed to turn the chroma adjustment up pretty high
to get what I’d call “normal” colors.
I’m guessing this is simply due to the fact that the liquid crystal color shutter can’t
produce quite as pure of a red, green, or blue as dedicated phosphor formulations can.
Colors also shift with differing viewing angles, and uniform images reveal the structure of
the LC shutter itself, imparting faint horizontal lines at the borders between each section.
And perhaps most importantly, scaling this tech up into larger screens would require
large color shutters, and who knows how practical that might have been.
Now I’m sure some of you have been screaming this at your screens for some time now, and
in fact some of you are probably already writing furious comments about this, so here goes.
It was not JVC who developed this technology.
It was the oscilloscope manufacturer Tektronix who came up with it, in fact they patented
it in 1983.
Giving it the name NuColor,
their motivation behind it was pretty clear as using a dot-mask CRT would
suuuuuuck for oscilloscope applications.
Using a phosphor-dot free CRT would fill with glee the hearts of thee!
said someone at Tektronix probably.
So, they came up with the idea of using an LC shutter over a black and white CRT to provide
coloration AFTER the image had been drawn.
Pretty neat thinking.
As far as why it took nearly two decades for the technology to find its way into video
monitors, well again that’s probably due to the much greater processing power needed
to extract and store the R, G, and B components of an analog television signal so that they
could be re-displayed sequentially.
Interestingly, I can’t find any reference in either the owner’s manual or on the device
itself to any patents at all, let alone those held by Tektronix.
Their patent didn’t expire until 2004, so presumably JVC would have needed to license
it from Tektronix.
Or perhaps the Tektronix patent just didn’t apply to video monitors.
Or some other thing happened.
But in any case, I do think it’s pretty neat that this technology made its way into
a color television monitor at least once.
It’s not exactly the same as the CBS color wheel system, but it gives a great approximation
of what that world would have looked like.
Thanks for watching!
I told myself I was going to make a quick video and, by golly, I think I did!
Wow!
Many thanks are owed to patron Brendan Terrett for suggesting this topic to me.
I had no idea these existed and it’s a perfect complement to the whole color TV saga.
It's also just...
really neat!
And of course, thank you to everyone who supports this channel on Patreon, with special thanks
going to the folks scrolling up your screen.
If you’d like to support my work with a pledge of your own, you can find out how by
clicking the link in the description or on the end screen.
Thanks for your consideration, and I’ll see you next time!
♫ cleverly smooth jazz ♫
Oh, [expletive]!
Ha ha!
I can't see... (wheezy laughs)
I can't see the teleprompter with these on!
(clears throat)
You might be familiar with the active shutter...
Active shutter?
You might be familiar with the active shutters used in some 3D glasses...
(exasperation sound)
Hey there.
Not too many bloopers today, huh?
That's OK. The music is fun, too.
Oh, and that thing the LC color shutter does is trippy and weird.
Glad I realized that. Helps make up for the lack of bloopers.
Do you know why chicken coops have two doors?
Well, if they had four they'd be chicken sedans.
This is not what captions are generally used for, but I don't play by the rules!
♫ LIQUID CRYSTAL COLOR SHUTTER ♫
♫ COLOR WITH A WEIRD TRICK ♫
SHUTTER POWER!!!