So now I'm wondering about different types of LCD.

At the bottom end, you have those silver ones they put in calculators. 
Usually a 7-segment one. I have a graphing calculator somewhere with a 
dot matrix LCD, but still silver, with no greyscale capability.

I'm wondering... Is there a specific *name* for this type of LCD? What 
does it cost to put one of these into your product? Like, if you're 
buying a couple of thousand of those things, what's the unit price? How 
much circuitry does it take to drive it?

At the other end of the scale, you have the stupid-DPI full-colour 
back-lit LCDs with touch sensitivity that they put into every mobile 
phone, ever. What do *those* things cost? I'm guessing you need way, 
*way* more hardware to drive it. (An entire framebuffer, for starters...)

I've heard it said that on "most" electronic devices, the buttons and 
lights are the most expensive part. As in, removing one button or one 
indicator light is a significant cost saving. So a toaster with three 
buttons is "much" more expensive to make than the same toaster with only 
two buttons. I'm not sure why this is; presumably because it's awkward 
to assemble a mechanical switch? (I.e., you have to have an extra step 
where a machine inserts all the moving parts into the right places.) I'd 
be interested if anybody has numbers.



I'm just wondering... High-colour LCDs are in even cheap phones now, so 
the LCD itself can't be all that expensive. So why don't more devices 
have these displays? For example, at the gym, the treadmill has a 
7-segment LED display, and three buttons for cycling through the menues 
and selecting the option you want.

So you've got this huge black slab of plastic, with a tiny, tiny little 
display in the middle. Why not just replace the entire thing with an LCD 
touch-screen? I mean, you damn well *know* there's a microcontroller in 
there. (Something has to drive the complex, unintuitive menu system!) 
You could show all the statistics *at once*, without having to scroll 
through them. (And in metric and imperial too.) You could show all the 
available programs at once, and a single touch would choose one. It 
would be drastically easier to use, and it would look hip and modern. 
(I.e., people would totally buy it.)

Naturally, a full-colour multi-touch LCD costs more than a 7-segment LED 
display. But then, you *know* a quality treadmill that's going into a 


expensive than that. In terms of material cost, it should be negligible. 

probably a more realistic comparison in terms of size.)

What *will* cost money, of course, is the cost of changing a product 
you're already making. Like, if you already make this thing, and people 
are already buying it, why change it?



I don't know if you knew, but a *huge* amount of lab equipment is like 
this. We had a temperature monitoring system. It could *only* 
communicate by RS-232. So we enquired about the networked version... It 
turns out this consists of an RS-232 to Ethernet adaptor, and then some 
software on your PC which makes the antiquated Windows 3.1 control 
software think that the remove RS-232 port is actually local.

Seriously, not only did the company not spend $1 adding an Ethernet port 
to the product itself, it also didn't bother to update its utterly 
ancient control software. When we upgraded to Windows XP, it stopped 
working, because it assumes that every user will have write permission 
to the C:\WINDOWS folder (which is here it stores TempConfig.ini, which 
has all its settings). It took me 20 minutes to figure out (mostly by 
*guessing*) which file it couldn't access, and manually tweak the file 
permissions. Seriously, they didn't even need to update the *software*, 
just fixing the *installer* would have been enough. But noooo...

(Did I mention the software comes on a CD-ROM, which contains four 
folders named "DISK1", "DISK2", "DISK3" and "DISK4", each of which is 
almost *exactly* 1.44MB in size. Hmm...)

Then again, maybe it's not the manufacturer we ought to be mad at. When 
a lab has a validated process for doing something, if you were to 
*change* that process, you would have to revalidate everything. This 
causes massive, massive inertia to change. This is why 100% of all lab 
equipment uses RS-232, and floppy disks and dot matrix printers are 
ubiquitous. (Also, *our* lab has nowhere near enough money; I don't know 
if that's common to all labs, or just ours. I imagine it's not 
*uncommon*...)

One time, we validated a new release of a program, and upgraded all our 
stuff. Then we found some really bad bugs in the software. I installed 
the hotfix, and we found it fixed all the problems. And then I had to go 
*uninstall* the hotfix, because it is not validated. So real bugs that 
are causing real problems and real lost productivity could not be fixed 
because nobody did the magic "validation" dance. Sad, really...



I'm sorry, what was I talking about? Oh, yeah, LCDs. How come (for 
example) my washing machine doesn't have one? I've only ever seen them 
on the most expensive ultra-luxury models. Surely this stuff isn't 
actually that expensive to manufacture anymore?

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