Capacitive touch better on 4.3" touchscreen?

Rayman

Somebody at the expo (don't remember who, but thank you) pointed out that NewHaven has new 4.3" touchscreens with a
multitouch capacitive screen.

Just had a chance to take a look... They're for sale for $58 at Digikey (part number NHD-4.3-480272MF-ATXI#-CTP-1-ND)

The resistive touch version is $38 (part number NHD-4.3-480272MF-ATXI#-T-1-ND).

But, it appears that the multitouch one as an integrated i2c touch interface.
So, that saves about 5 or 6 dollars maybe compared to the resistive, which needs a touch interface chip.

Do you guys think capacitive multitouch is worth paying ~30% more?

I guess this would allow people to capture gestures...
Would be worse for things like signatures and drawing though, I think...

DavidZemon

I would happily pay 30% more for capacitive touch screen. I hate resistive ones. Capacitive is so much easier and takes a lot less pressure. Unless you're really tight for money, I'd go for it.

Don M

Ray- I was the one that told you about the screens at the Expo. I have one of them I ordered when they became available from New Haven. I dislike resistive screens for several reasons- they have a "soft" overlay that easily scratches and becomes ugly, they require pressure that at times seems uneven at various locations on the screen. The cap touch screens are glass, seem much more durable and looks like a better finished product.

Regarding your comment about multitouch being harder to use for signatures, etc., I would disagree and only because they are used in todays latest cell phones and applications that require a signature (think of Square credit card app) and drawing seem to work ok.

Do I like the 30% premium? Not if I have to but that will come down as they become more popular in this arena.

Ray I'll be your first customer when you come up with an adaptor board to utilize this display with the cap touch interface & backlight control etc.

Rayman

Thanks Don.

I'm 99% sure our new NH4 adapter and up-coming 4.3" plugin for the DVI Graphics shield, will work with these displays.
But, you'll have to buy the connector and run your own wires for the I2C touchscreen controller...
(I'm about to order one so that I can make sure this is true).

I asked Newhaven support and the underlying display is exactly the same as the resistive one, with the same pinout.

For PSB2, I think I'll support both resistive and capacitive versions. But, it sounds like maybe I shouldn't bother with resistive at all...
There seems to be strong opinion here that capacitive is well worth the higher price...

Don M

Just my opinion- the resistive touch is ok for simple cheap projects and prototyping but for a finished product the capacitive touch is the only way to go.

I think it would be neat if you added the I2C socket to your adaptor board so that the tails can all connect to the same board... would make for an all in one neater solution.

Dr_Acula

I agree - capacitive is much better than resistive.

I've got an android "pandapad" with a nice 8" display but it is a resistive screen and it misses many keypresses and has trouble distinguishing between a "swipe" and opening a program. So many of the swipes mistakenly open programs. The keyboard is difficult to use and that is on an 8" display, whereas keyboards on a much smaller iphone with a capacitative display are much easier to use.

I agree with Don - resistive is useful for prototyping but capacitive is for a finished product.

nightwing

Nice.. Digakey also have a 5" for 68.... ^_^

Don M

I forgot to mention I also received one of the 5" displays too. Look forward to checking these out sometime soon.

the-new-guy

Are these projected or surface capacitive touch? I can not look them up now since both sites mentioned seem to freeze up my current device.

Rayman

I think I read that they are mutual capacitance touchscreens, which I think means projected.

BTW: Was reading the touchscreen controller chip datasheet a bit... It's much more complex than I thought...
It's basically it's own little MCU with eeprom and ram and a program... Has several I/O connections to the panel...
I'm curious now as to whether or not Prop 2 will be able to control one of these panels directly...

the-new-guy

I am fairly certain that mutual capacitance is used in both methods.

Rayman

Could be... Wikipedia lists mutual as a type of projected... Maybe the datasheet says for sure...

Which type is better?

Rayman

BTW: I'm having these little breakouts made for the Newhaven 4.3" CP interface:

Hopefully, this will provide a relatively painless means of connecting to the touchscreen...

Should allow both NH4 and 4.3 plugin boards to use either resistive or capacitive screens...

Don M

Ray- Let me know when you have these ready. I'll buy a few. Will they include the connector already soldered in place?

Rayman

Should have them ready in 2 weeks. Yes, I'll solder the connector on (at least I'll try to...).

I'm interested to see how different these screens are...

the-new-guy

Rayman wrote: »

Which type is better?

Projected allows for multitouch, surface does not.

Edit: Apparently there is some tech out there for surface multitouch... I can't imagine that it would be as accurate as a projected though. Surface is also more durable. It can be no more than a piece of glass.