On 28/04/2014 08:59 AM, scott wrote:
>> Presumably what you do is make a translucent layer which has inclusions
>> inside it that refract the light. So the outer surfaces are smooth, yet
>> you still get colour. Hard to see how you could do that cheaply though.
>
> Well you could just make it in two parts, so long as the two materials
> had different refractive indices. A bit like how a CD is made. Maybe you
> could use some photo-etch process on the first layer, borrowed from IC
> manufacturing?

That sounds quite plausible. Although probably not as cheap as just 
spraying some dye onto things, which is what we do now.

>> Has anybody invented a UV coating that actually works yet?
>
> Yes, people rely on them not to get skin cancer or go blind! Also the
> one on your car paint works. I'm sure you can find spectral response
> curves if you are interested.

Interesting. I was under the impression that UV-resistent coatings are 
just overly-optimistic marketing, and in reality none of these coatings 
actually work.

>> I'm sure things have changed. Just perhaps not as rapidly and
>> dramatically as the original revolution.
>
> You could argue that in some ways things are changing even faster now.
> Continuing with your plastics example, at the start hardly anyone used
> plastic and development was slow. Today plastic is used in almost
> everything and there are millions of different types. I'm sure if you
> plotted a graph of the number of new plastics invented against time it
> would be going upwards.

Really?

OK, really ancient plastics weren't very good. But the plastics I see 
today and the plastics I saw 30 years ago seem pretty much identical in 
every respect. What's changed?

>> This is very interesting. From what I can gather, the primary problem is
>> the absurd amount of computer power required.
>
> Indeed, it looks like they had to spend most of the effort trying to
> reduce the computing power needed whilst maintaining a decent image
> quality. Maybe in 5 or 10 years someone will come back to this
> technology and it will be able to take off.

Much like how we had CDs for decades before DVDs were invented. Clearly 
a lot of people *wanted* DVDs, but the necessary computer power was 
simply unavailable.

Then again, we're trying to simulate the interaction of billions of 
photons in a large 3-dimensional space. Maybe there are 
quantum-theoretical reasons why you can't do that any faster than the 
real world can? (At least, not without using a computer many times 
bigger than the real-world system it's trying to simulate!)

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> Interesting. I was under the impression that UV-resistent coatings are
> just overly-optimistic marketing, and in reality none of these coatings
> actually work.

One of the first image results from google gave this:

http://www.alpineastro.com/filters/uv_ir_cut_specs.htm

That's a pretty sharp fall-off below 400 nm. Whether it works or not is 
unquestionable, what is usually up for debate is whether it's actually 
useful on a camera. On skin, eyes or paint of course it works and is 
useful.

> OK, really ancient plastics weren't very good. But the plastics I see
> today and the plastics I saw 30 years ago seem pretty much identical in
> every respect. What's changed?

What you see today is them used in many places where they simply 
couldn't be used 30 years ago because plastics with the required 
performance didn't exist or were too expensive to manufacture. Car 
bumpers were metal or fibre-glass that got dented or cracked, pipes in 
your house were copper, anything involving even slightly corrosive 
chemicals was stainless steel. Today plastics can be and are used in all 
those places, ultimately making things cheaper.

Then there are all the things the consumer doesn't even notice. Like 
plastics that are easier to mould (more complicated shapes are possible 
to be made faster with finer details), possible to process in thinner 
films, flame retardants that are environmentally friendly, stronger and 
stiffer plastics that enable things to be made with less plastic for the 
same performance etc.

The software we use here for simulating the moulding of a plastic part 
(to make sure it will fill correctly and not leave any sink marks, weld 
lines etc) has a built-in database of plastic materials to choose from. 
There are over 10000 of them, and there are plenty not in the list. They 
have all been developed for a specific reason, and most of them recently 
(not 30 years ago).

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> On 28/04/2014 08:59 AM, scott wrote:
>>
>> You could argue that in some ways things are changing even faster now.
>> Continuing with your plastics example, at the start hardly anyone used
>> plastic and development was slow. Today plastic is used in almost
>> everything and there are millions of different types. I'm sure if you
>> plotted a graph of the number of new plastics invented against time it
>> would be going upwards.
>
> Really?
>
> OK, really ancient plastics weren't very good. But the plastics I see
> today and the plastics I saw 30 years ago seem pretty much identical in
> every respect. What's changed?
>

First, You have a tendency to be totally oblivious to what's around you. 
  You wouldn't see the changes if they hit you in the face (in fact, one 
of those changes is actually sitting right there on your nose!)

Second, you worked in the chemical industry for over 10 years.  I'm sure 
you're familiar with the names 3M, Dupont and BASF, just to name those. 
  Don't think for a second that these companies don't have large R&D 
depts that work round the clock trying to come up with newer compounds 
that are easier to work with, thereby reducing production costs, more 
resitant, less dangerous, or biodegradable, just to name those 
characterisitcs, thereby increasing their marketing value.  They're not 
just sitting there waiting for Nylon(tm), Teflon(tm) or Kevlar(tm) 
royalties to pad their bank accounts.

Many of these plastics will have special medical or industrial 
applications, but here are a few examples of everyday uses that you may 
have seen:

Have you noticed how nowadays most eye glasses are made of plastic? 
Clear plastics with higher IOR (sorry for getting slightly on-topic for 
P.O-T) than glass were unheard of 30 years ago.  The progresses made in 
the domain of contact lenses is even more impressive than that of 
conventional glass lenses.

The same goes for the plastic covers on most car headlights.  The 
average human doesn't often stop to admire the complexity of a car's 
tail lights, - unless you're stopped behind a Lamborghini at a stop 
light - but there's been tremendous developments made in that area, too.

I know you don't have kids, but the plastics used in baby bottles and 
toys have also changed a lot in the last 10 years, due to various "Won't 
anyone think of the children?!?!!!?" reasons.

The "technical" garment industry has also greatly benefited from these 
new polymers.  You're a skier, so you've most certainly seen the 
74732327523 tags that are sewn or attached on a new ski jacket or 
gloves, touting the amazing breathability, yet still impermeable, 
feather light, yet warm as a mammoth pelt, machine washable, yet won't 
fade properties these clothes now offer.

> Then again, we're trying to simulate the interaction of billions of
> photons in a large 3-dimensional space. Maybe there are
> quantum-theoretical reasons why you can't do that any faster than the
> real world can? (At least, not without using a computer many times
> bigger than the real-world system it's trying to simulate!)

To perfectly emulate it, we'd need at least one processor per photon, 
able to do all the physics calculations and share Heisenberg-principle 
violating amounts of information with other processors, in real-time.  I 
think Slatibartfast was on the right track!

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> OK, really ancient plastics weren't very good. But the plastics I see
> today and the plastics I saw 30 years ago seem pretty much identical in
> every respect. What's changed?

Since Francois mentioned 3M, that reminded me they make lots of 
*plastic* optical films that are used in your mobile phone to improve 
brightness, viewing angle and sunlight readability. Another area that 
has been continuously improving over the last decade and will continue 
to, but which most consumers wouldn't know about.

Or surely you've heard about 3D printers recently? The materials they 
use (the professional ones, not the hobby ones) are state-of-the-art 
polymers to give the final piece properties as close as possible to 
traditional injection moulded plastics. It's not like those materials 
existed 30 years ago.

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On 29/04/2014 9:23 AM, scott wrote:
> What you see today is them used in many places where they simply
> couldn't be used 30 years ago because plastics with the required
> performance didn't exist or were too expensive to manufacture. Car
> bumpers were metal or fibre-glass that got dented or cracked, pipes in
> your house were copper,

Go back another twenty years and they would be mostly lead popes. :-(


> Then there are all the things the consumer doesn't even notice. Like
> plastics that are easier to mould (more complicated shapes are possible
> to be made faster with finer details), possible to process in thinner
> films, flame retardants that are environmentally friendly, stronger and
> stiffer plastics that enable things to be made with less plastic for the
> same performance etc.

You did not mention easier to join and repair. No soldering and the 
compression joints are barely tighter than finger tight. Small Stillsons 
or pipe wrenches are all you need.

You don't often here anyone or anything being described as plastic in a 
derogatory way, nowadays. The image has changed.

-- 
Regards
     Stephen

I solemnly promise to kick the next angle, I see.

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On 29/04/2014 9:09 PM, Stephen wrote:
>
> Go back another twenty years and they would be mostly lead popes.

I think I meant pipes. Lead pipes not lead Popes. :-)

-- 
Regards
     Stephen

I solemnly promise to kick the next angle, I see.

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On 29-4-2014 22:19, Stephen wrote:
> On 29/04/2014 9:09 PM, Stephen wrote:
>>
>> Go back another twenty years and they would be mostly lead popes.
>
> I think I meant pipes. Lead pipes not lead Popes. :-)
>

Somehow, those /lead popes/ trigger my imagination... :-)

Thomas

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> Go back another twenty years and they would be mostly lead popes. :-(

That's a good one :-)

> You did not mention easier to join and repair. No soldering and the
> compression joints are barely tighter than finger tight. Small Stillsons
> or pipe wrenches are all you need.

Two more. No annoying metal banging noises when the heating turns on or 
off (light sleepers can have the heating come on before they wake up). 
And because the pipes are somewhat bendy you can move things about 
without having to disconnect pipes. Painting behind my radiators is 
easy, I can just lift them off, rotate through 90 degrees and rest them 
on a bucket or something, no plumbing needed.

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On 2014-04-24 14:32, Francois Labreque wrote:
> Andy has also assured me that iPads, Kindles, Nooks, and the various
> android-based thingamajigs weren't tablets at all, because tablets were
> 2 inch thick laptops that weigh 20lbs and on which you write with a
> Palm-Pilot stylus.

Hear, hear!  Well, augmenting the specifications a little, but I concur 
that these newfangled touch-only widgets aren't REAL tablets...my 
current dream machine is the Fujitsu Stylistic Q584.  2560x1600 screen, 
10.1"x7.12"x0.39" with proper Wacom pen input, weighs 1.4 lbs.

...oh, and it has loads of other bells and whistles, if you're into 
those things.  But dat display...over four times the resolution of my 
Fujitsu Lifebook (which, at six years old, is rather closer to your 
referred attributes, ahem), in a smaller area.  And it's less than a 
thousand dollars!

Mind, the Q584's specs are rather unusual and extravagant; most 
pen-input tablets are still poking around the 1280x800 neighbourhood.

Also, re. OP:  It's the future.  I was promised flying cars!  But I 
don't see any.  Why?  WHY?

--
Tim Cook
http://empyrean.sjcook.com

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>> OK, really ancient plastics weren't very good. But the plastics I see
>> today and the plastics I saw 30 years ago seem pretty much identical in
>> every respect. What's changed?
>
> Since Francois mentioned 3M, that reminded me they make lots of
> *plastic* optical films that are used in your mobile phone to improve
> brightness, viewing angle and sunlight readability. Another area that
> has been continuously improving over the last decade and will continue
> to, but which most consumers wouldn't know about.
>
> Or surely you've heard about 3D printers recently? The materials they
> use (the professional ones, not the hobby ones) are state-of-the-art
> polymers to give the final piece properties as close as possible to
> traditional injection moulded plastics. It's not like those materials
> existed 30 years ago.
>

At this point, this becomes obligatory:

http://www.youtube.com/watch?v=PSxihhBzCjk

-- 
/*Francois Labreque*/#local a=x+y;#local b=x+a;#local c=a+b;#macro P(F//
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