Loctor's IR Pen Part I

Gosh! Its more than a week now and I still have not made the pen for Loctor. Its a very simple device, actually. All you need is a switch, an IR LED, battery and a current limiting resistor. The hard part is to look for a nice little pen to house it all in. Needless to say, that pen would be "sacrificed" for this project.

And I have not located a perfect pen until today, when we went to Cziplee Bookstore. This a RM4.30 (which my Wife said was expensive) Whiteboard Marker which retracts like a retractable ball-point pen. All week I was looking for a thinner pen but alas, although I found it in Prai, its not easy to fit in a push-button switch since the pen is made of aluminium and if I try to do it, I would have broken it instead. Actually, to over come the switch problem, I could fit in a very sensitve push-button switch in front of the IR LED so when you start to write on it, the pressure you exert by pushing the pen down would have closed the circuit. But then, therewould arise other problems namely the LED would wear itself out on the surface which acts like sandpaper. Or it might affect the surface instead.

So, to overcome this problem, I would therefore need a transparent teflon 6mm sphere to put in front of the LED. Then, reality hit me. Where the heck am I going to find such thing, even if it exists in such a short time?

So, the only thing I can do is to gut a pen and stuff everything in it.....

Why I chose this market apart from the rectractable gimmick?
Well, the opening is ideal for the 5mm LED which I originally &
stubbornly want to keep the pen's retractable feature.Problem
is, the power to the LED would then have to be those itty bitty
watch batteries, which would last as long as a few hours, I think.

Dissecting the pen, you would have, from left to right, the slip, the
outer casing, the internal mechanism and lastly, the ink cartridge
itself. Yes, its refillable and now, I regret chosing this as sacrifice.
Ha ha ha ha!

Note that in the construction for this pen, there were no screws or even
glue. Everything sort of snaps into place. The black clip does two function
here. It sort of holds everything together and also acts as the locking
mechanism when you push the end.

Now we come to the interesting part; the innard which houses the ink
and also the tip.

Just to remove the ink cartridge, you have unscrew the cap which acts
as the holder and also to make sure its airtight too.

Now, the business end. See the small black round thing? Its a protective
cover for the tip. When you push the pen, it will twist open and the tip
will pop up.

See what happens when I push it? The cover swivels open

And now, the tip comes up. Cool or not?
They have to do this to prevent the ink in the tip from
drying out or there would be a lot of customer returns

In the next post, I will show you how I complete the pen (If I have the time, that is). Until then keep all your pens away from me, OK? Bwahahahahhahaa!