Using MEMS to Miniaturize Mobile Phones

securitas writes: "The NY Times has a feature on using microelectro-mechanical systems (MEMS) in cell phones to replace bulky passive components like the filters, resonators and duplexers that make up most of the size of today's phones. In theory, they say, you could have a cell phone in a ring on your finger. Besides making everyone seem like James Bond, a ring-phone would give new meaning to the phrase 'Talk to the hand.'"

Comments

Great....

[tfurrows]

So now we're going to have a bunch of yuppies talking to their fingers while they drive.

Does this mean people are going to get pulled over for talking on their cell (in areas where it's illegal), when all they were really doing was picking their nose?

What an injustice... what a travisty....

Ring phones

[Restil]

Even with electronics that use a fraction of what today's phones use, to reduce the size of the phone will reduce the size of the battery you can carry with it. A ring phone can't feasibly hold more than a watch battery.

-Restil

One Ring to Bind them?

[Matey-O]

Actually, One ring says I'm committed to my wife. The other Ring shows my commitment to technology!

Shameless plugs

[Doctor K]

I am working in the MEMs area these days. So here are some shameless plugs.

Here
is an general interest article from the group in which I work with some details oriented towards these types of mesoscopic MEMs.

Here
is a neat picture of a Mesoscopic MEMs device (an acceleratometer resting on top the middle part of the "8" in a 1998 penny.

And though my research at Berkeley wasn't MEMS oriented, Berkeley MEMS is pretty active. Here is a link to that.

As the article points out, MEMS are finding applications in cell phones because it is easy to make very small RF filters using inertial effects to provide inductive-like impedences. (In the past, the inductive like parts of a cell-phone filter would either be done with spiral inductors, which are unwieldly or via other microwave circuit voodoo.)

However, beyond cell phones is a grab bag of MEMs applications already at or beyond the prototype stage:
- Car air bag detectors (the above accelerometer)
- Laser gyroscopes
- Projection displays (pixel mirrors arrays)
- Optical fiber switches
- Medical applications (microfluidics, bio-chips, ...)
- Remote sensing (minaturized microphones, or in the future, smart dust)

Enjoy
Kevin

Implants

[Zeinfeld]

A while back some of us were sitting round at the IETF discussing the various techno gadgets we had bought recently. Jeff Schiller went first and showed everyone a ham radio the size of a matchbox. Then Steve Bellovin showed people his watch running Linux. All I had was a cheezy Palm VII running a Lisp machine emulator.

The last guy to go is one of those crypto dudes who wears all black. He holds out his hand and taps his palm a few times. Then after a brief pause he starts speaking to someone as if on the phone, which it turned out he was, this dude had a cell phone implanted into his palm and skull!

Anyway we continued drinking for some time (it was IETF after all) and the dude asked us to watch his laptop for a while while he went to the little boys room. We had some more drinks and were about to leave when someone pointed out that the dude had not returned yet. So I went off to the bathroom to find him.

I find the dude bent over the can with his legs stretched out and a bog roll stuck up his ass. Immediately I think the dude has been mugged. "Hey whats up, you OK?" I ask. "No I'm fine", the dude replies "I'm just waiting for a fax".

Re:Coltan

[Hal-9001]

For people like me who had no idea what coltan is, see this article. The short version is that columbite-tantalite (coltan) is an ore than can be refined into tantalum, which apparently is a very good dielectric for making capacitors. This means that it's not just in cell phones but probably in every electronic device you own.

The controversy over coltan and the Congo seems to revolve around two issues. One is that Congo's neighbors seem to be exploiting its coltan resources, i.e. smuggling coltan and exporting it as their own product. Another is the environmental impact, since illegal mining operations probably care as much about the environmental impact they have as they do about the law.

All of this so far is off-topic, but if rf MEMs could replace capacitive filters and resonators, it could help reduce the demand for coltan. This feeble attempt to be on-topic is purely speculative, though, as I am not a wireless engineer and the NYT article lacks details about the materials being used in these devices.

It could be useful, actually

[kevinadi]

Although a ring-sized phone will be a practical impossibility, it can be used in a more practical way if it is combined with something else.

The current "best" PDA-phone combination is arguably the Nokia 9210 (or yet-to-be-released 9290 in the US). Although the size is perfectly ok for myself, the weight is not. A ring-sized phone embedded inside a PDA could be the planned direction for this miniaturization.

Palm is too bulky a unit to be used as a phone, contrary to whatever Handspring say about its Treo. The 9210 is too heavy and too thick for most people. Imagine a phone with Palm functionality, the integration of 9210, and the weight of 80g. This ring-phone technology could be the answer to our prayers.

Cell phone in your ring?

[sporty]

Who would wanna cell phone in their ring? Keep it in your shoe like any professional spy.