After tearing down the scanners and being slightly disappointed that I wouldn't be able to mash this thing up nearly as fast as I thought (see The Tear Down), I decided to go to town on the scanner heads. I suspected some nice toys to play with down inside. This time, I would not be broken hearted!!!

Here we have one of the heads. There are three scanners, consisting of two of one model, and one of a second model. Since the technology and layout are roughly the same in both models, I will only show you one setup here.

Lets take it apart!!!

Holly anti-climatic Batman!!!
Yeah, that's right. Its mostly a box of air.
But what goes on in that box of air, is mind (and light) bending!

Under that metal strap in the center is a lens. Towards the bottom of the image, on the bottom side of the case is where the scanner's line camera sits. It looks through this lens at the mirror at the top of the box.
Now, it is important to note that, when looking through this lens, everything appears normal, if not incredibly small. However, when two points (the 'eye' or camera, and the 'image' or mirror) are at precise locations, the lens will actually flip the image around. Optics.. so cool.

The geometry of this particular setup is such that the width of of a typical page of paper is reduced to somewhere around 1 inch by the time it hits the camera.

There are a network of front surface mirrors to help the lens do it's work. A front surface mirror is one in which the optical coating is on the front of the viewing surface, rather than the back. On a typical household mirror, you actually look THROUGH the glass, and the mirrored surface is on the back. This is fine for our daily needs. However, there is an ever so slight distortion as the light passes from air to glass. It is a media interface distortion. The most commonly known example is trying to catch a fish in a fish tank. It is never where it appears to be. This is due to light being bent as it passes from water to air, before entering your eye.

A front surface mirror is much better for tricky optics (especially lasers), because it reduces that interface distortion considerably.
For example, we wont notice looking into a typical mirror. However, if we were to shine a laser at the mirror, we would end up with the dot appearing at the wrong place at the far end. A front surface mirror reduces this error to virtually zero.

Let's get back to tearing things apart:
Take a look at the first picture again. The electronics board at the top is the camera head board. To the right of that is a yellow transformer. This is for the inverter circuit for the flo lamp. When you turn your scanner on, you get that bright beam of light coming out. This yellow transformer makes that possible. This board plus the light tube connected to a 12 volt supply is quite bright for such a thin little tube.

Here is a shot of all the parts stripped out:

So, what to do with all my goodies?
* Front surface mirrors - A new project: laser spirograph. I'll have a project page up soon for it. Hopefully, this will be a THS kit in limited quantities.

* Lenses - as it turns out, they are great for macro photography. I held one up to the lens of my cell phone and cranked the digital zoom up. Here is an example:

That card it is sitting on is about the size of a business card (It's a discount cupon from BookOFF). There are more macro photos in the ScanRap image gallery. Check them out.

* Flo lamps and inverters - I dont know yet. But I have three tubes and one square face lamp (from a negatives / slides adapter). If you have an idea, lemme know. I'll donate.