Hardware/Software UI Relationship

David Duardo dduardo at gmail.com
Tue Jul 17 17:32:46 CEST 2007

That's great that you have the dexterity to use your fingernails to poke
at tiny  buttons, but what about the wider audience? Do you think Aunt
Jane or Uncle Leo would feel comfortable operating a phone with such
tiny buttons? Is this even a relevant question? Is the phone being
marketed to them? If not, then who?

Before we dive in and start creating user interfaces from scratch we
need to have some sort of basis of who will be using the phone and what
they will be doing. Right now it is unclear which direction the
community and FIC want to take. I have my personal ideas, but I want to
get a consensus from everyone else.

The Neo1973's LCD is 43mm x 58mm. Let's say you do 5 columns and 6 rows
(30 buttons). In order to fill  the width of the the LCD each button
width should be button  8.6 mm. A reasonable height is 8 mm, which is
less than the width of the button. 6 rows times 8mm is 48mm. That leaves
10mm for everything else. Subtract another 8 mm for navigation buttons
and you literally have 22 pixels to have some sort of status bar plus a
place to display the stuff you are actually typing. There simply isn't
enough room.

The iPhone's LCD is 50.8mm x 76.2mm. Let's take the 5 columns and 6 rows
again. In order to fill  the width of the the LCD each button width
should be button 10.16 mm. A reasonable height again is 8 mm. This time
you have 28.2 mm for everything else. In this case, not only are the
buttons 15% bigger, you have plenty of room for everything else. 10.16mm
x 8mm should be moderately comfortable.

I have an alternative idea for a character input system on the Neo1973,
a linearized rotary dial, but it requires that the LCD to have certain
friction that would allow for the finger to slide easily down the side
of the screen. My current phone has a screen that would work with this
system, but I'm not sure if the Neo1973 will.

Hardware needs to be conscience of software and software needs to be
conscience of hardware. And this just doesn't go with the LCD, I want
this idea of the hardware/software UI relationship throughout the whole
product. The LCD is merely an example.

- David

Lars Hallberg wrote:
> David Duardo skrev:
>> This is where I ran into trouble As high resolution as the the LCD is,
>> it simply is too small to be used with a finger based user interface,
>> which is what most people would want to use on a cellphone because it is
>> most convenient. At the upper bound, with the Neo1973, you can have 3
>> columns by 4 rows of buttons that are of a comfortable size (.5x.5
>> inch^2). Actually, the buttons can be slightly smaller and more compact,
>> but I'm estimating for people with slightly bigger fingers. You can see
>> can see what I mean in the following image:
> My current phone have a touch screen and a UI designed for stylus.
> The QUERTY keyboard is 14 keys wide on a 55mm wide screen (and it has
> bevels). That makes 3.9 mm per key. It's a bit painful, but I use it
> with fingers all the time (fingernails rather). Keys twice that size
> should work just fine.
> 5 colums and 7 rows of buttons should be usable on the neo... however
> a clever UI should generally need less... but that's the density I
> would use for text input.
> ... And my fingers are not huge... but fairly big.
> /LaH
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