h a l f b a k e r y
Yeah, I wish it made more sense too.

meta:

account: browse anonymously, or get an account and write.

 user: pass:
register,

Low-Wattage Rasterized Scanning Toaster

Looks like a solid metal tent...
 (+8, -2) [vote for, against]

There is, or soon will be, a massive need for low-wattage toasters.

I was going to leave that as an unsupported statement, because it is so obvious. However, since a couple of people will object, here is the rationale. The idea of living "off-the-grid" with all electricity being generated by alternate sources (solar, wind, hydro, refuse fermentation, what-have-you) is becoming more popular. Many of these alternate sources are not good at handling "peak" loads. Go around your house and see what wattages everything uses. You'll find that dropping two slices of bread into the slots and pressing will result in a "peak load" in many cases.

So... how to produce toast with only five watts of input power? Simple. Don't toast the whole thing at once.

The idea of a toaster is fairly simple - it involves taking a pre-cooked bread item, and using radiant energy on the un-crusted cut sides to accomplish two tasks: first, driving off some of the moisture, resulting in a more rigid, less flexible slice of bread; second, partially carmelizing the sugars contained in the bread, tremendously enhancing the flavors thereof.

Take the five watts of input power. Use it to drive a one-watt infrared laser. This is mounted on a stepper-motor driven scanning frame. Pointed upwards at an angle, the beam strikes a pivoting mirror; its slow eccentric drive moves the beam back and forth bi-directionally across individual scan lines.

A one-watt laser is a pretty powerful dot - you can easily produce a line pitch of 8 lines per inch, and should not be a problem, with carefully designed optics, to go as low as 5 lpi. (The lower the resolution, the fewer times you have to scan across the bread, yeilding a quicker toast.)

After finishing one side, conveyor teeth pick up one edge of the half-toast and lift it up to the apex of the triangle form of the frame. Then a similar set drags the bottom edge across, from which position the top falls down the unsupported side, completing the flip.

You'd expect your toast to come out cold. It would, were it not for the fact that the toaster is sealed and insulated. Over the course of the cycle, the waste heat in the scan chamber is captured and keeps the toast from cooling.

You'd also expect your toast to be dried to mega-crouton-ness. Again, no, because of the seal. In fact, this would lead to soggy toast, but for the inclusion of a pair of dessicant cartridges - one of which is actively absorbing the moisture from the chamber (to a user settable level), while the other is recharging in the waste heat from the laser pump drive on the outside of the chamber. The exchange of cartridges is lever actuated every time you open and close the chamber.

As mentioned, the final moisture level is user controllable, as are the exposure settings, margins, and single-side / double-side toasting. A bit of additional hardware and software may lead to low-resolution printing or copy capabilities.

Since this will take a while, there is a piezo reminder alarm to let you know when the toast is up.

 — lurch, Jul 25 2007

A situation with a very low available "peak" power. Toaster_20Shoes
My inspiration. Even though it might not be very inspiring. [lurch, Jul 25 2007]

Toast Text Messaging Toast_20Text_20Messaging
The logical extension of this idea - if you're doing a raster scan, why not encode some information in the signal? [hippo, Jul 26 2007]

Gas display Propane_20fueled_20video_20display
which, as [8th of 7] notes, can toast toast as well [lurch, Jul 27 2007]

USB Toaster http://store.theoni...b-toaster-p-71.html
[globaltourniquet, Aug 06 2007]

 I'm somewhat dubious about the energy calcs, and would prefer a more scientific analysis.

Nevertheless, I like the idea of beaing able to toast the Mona Lisa or face of Jesus on a piece of bread.
 — nuclear hobo, Jul 25 2007

 The only issue I see is that regardless of the method of achieving it creating a piece of toast(ie the heat required to achieve the toast effect) is pretty much fixed so while you are using less energy you will need to take much longer to achieve the same effect with only a small improvement in the net power consumption based on improvements in efficiency in transferring electricity into infrared energy.

 Put another way your new toaster is still going to hog power it will just do it more slowly.

The neat thing hear is that this is a short step to a toast printer, allowing you to print messages on your toast.(sorry I missed that little bit at the very end about printing, was getting punchy after reading the whole thing)
 — jhomrighaus, Jul 25 2007

 A focussed beam will toast faster. Consider leaving a newspaper out in the sun, it doesn't burn, ever. But use a magnifying glass and you can burn lines into it.

 I think the laser toaster would be much the same, cooking the top layer but not penetrating very far.

<pedant> It wouldn't be rasterised unless you turn off the laser every time it moved, in which case it wouldn't be scanning</pedant>
 — marklar, Jul 26 2007

 i like the idea (+), especially because it involves food and lasers, but also because some thought has actually been put into a problem that is inevitable.

 ...but, if you're gonna use a laser to cook toast, why not go big? i want 'femtosecond toast'. i also want an optical tracking and targeting system that allows me to throw my slice of bread in the air, and catch a piece of toast.

yeah, it would take a lot of power to do this - that's why my toaster would be equipped with the latest super capacitors that can efficiently trickle-charge all day and night,
 — TIB, Jul 26 2007

[marklar] - re: //pedant//ry: yes, it looks like I'm scanning continuous lines across. However, I can't get the toasty-darkness sensor to look directly at the beam spot and get good results - so I have to trail somewhat and make corrections after the fact. The uneven surface also creates discontinuities in the colorization, so some averaging is required. Therefore, adjustments to beam scan speed are quantized into short segments. Adjustments are limited in magnitude, yielding a blur effect, but a map of drive rates would be a raster of descrete levels.
 — lurch, Jul 26 2007

Use a trickle-charged supercapacitor to give it a final blast when it's been pre-carbonised.
 — wagster, Jul 26 2007

hmm. A toaster must the most inefficient technology possible, now that I think about it. We go through huge losses converting coal fire into electricity, huge losses transmitting it, then huge losses turning it back into heat.
 — GutPunchLullabies, Jul 27 2007

So GPL, you are saying we need a coal fired toaster?
 — Galbinus_Caeli, Jul 27 2007

Definitely! Who wouldn't buy a toaster that fired coal?
 — wagster, Jul 27 2007

 wow, you have created the most expensive toaster ever. You really need to incorperate a USB connection and GPS linkage to the main LASER assembly, then some kind of rotater splint to the chassie.

Why not just use a combustable source to toast the bread? Natural gas maybe? Seams to be much simplier in practice.
 — evilpenguin, Jul 27 2007

// Natural gas maybe? // Sure, but I already did that <see link>
 — lurch, Jul 27 2007

 The downside of this is that the toaster will not toast the bread to a great depth. Part of what makes the conventional toaster do such a nice job is that it is heating the entire piece of bread through and through. The surface is browned, and so is the next couple of millimeters. I worry that this idea would toast the outermost surface and leave me with toast that had a gooshy core.

I also worry that it would take a long, long time. Reduced wattage = longer exposure time in order to impart the same amount of energy to the bread. And isn't a laser a really inefficient way to convert electricity to heat? Wouldn't a scanning heating element be a more effective way to reduce the momentary wattage? I think, ultimately, the net watt-hour expenditure must remain the same, and with the scanning heat laser, probably go up.
 — elhigh, Jul 30 2007

On this subject, look what you can buy from the onion for someone as a gift (link)
 — globaltourniquet, Aug 06 2007