Don't sell digital tablets short. Check out the Cintiq 21UX. A little pricey (okay... very pricey), but exteme accuracy and ease of use.
I thought your reason for starting this topic was to find out information about light pens, not to find a solution that you could use. What exactly is it that you want to do, and what is the ideal solution in your opinion (ignoring whether or not the solution exists)?
(Thanks for the link.)
Cintiq 21UX. Well... yes, it's very pricey (3000$)! First time I heard for WACOM firm was two days ago in some computer shop when I was looking for some solution on this issue of mine - I didn't even know the price ratios so I coudn't compare - complete lack of perspective for these things (they too were saying that WACOM's products are top class in this domain (they showed me some WACOM tablet (costing 85$ or so - I don't remember...))).
About your question:
Rule: The more comparable to drawing on paper, the more ideal is the device for drawing using computer... (logical...) ...and of course - price...
That's why I stick to the Light-pen - I mean: (to answer your question) if it works correctly (if it's precise) - it's the best thing there can be(!) - IDEAL SOLUTION (to use your term): just a pen (and you use your monitor) - no aditional robust devices equals less money to pay.
IT IS the reason for starting this topic (information about light-pens themselves). That's the main talk. That's the point.
For example: maybe light-pen gets a wrong input if you change it's angle (picks up a wrong line) - I don't know, maybe someone else does?
It's all so fishy...
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(Just by-the way: CONCEPTUALY second best solution (I think) is that touch-screen add-on (a transparent layer for monitor and a pen - it can't be that pricey); but also don't know how good it is.)
Light-pens - definitely... it's the ideal solution (that's the best concept - no matter what (but does it really work - that's the only question I ask here)); and I started this topic because I was suspicious about it's quality because there's not much evidence of lightpen for PC usage on the Internet, not to mention that I can't find them in the computer shops here (not a single model!). (I have some cheap plastic can-see-LED-on-tip lowsy light-pen for Commodore 64 for a long time now, though... never worked...).
The best thing for me would be if someone would come and say - "I use light-pen, it is very precise, fast and reliable - check this one!", beacuse I prefere that solution - that's the first one on my priority list anyway (I insist on it - that IS the whole point of this topic...).
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On the other hand that 'Cintiq 21UX' concept sounds like the best possible in professional terms (ultimate) solution for drawing - ideal (the price part on the other hand doesn't seem like it)...
(actually - it's an LCD portable touchscreen monitor! isn't it? They just call it a "tablet", but let's stop kidding, it's more than a tablet (much more...)).
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Anyway... That day (two days ago) I bought a ' Genius WizardPen 5"x4" ' (
http://www.geniusnet.com.tw/product/...1.asp?pdtno=70 ) tablet (a simple thingy really - flat board with USB cable, pen with AAA battery) for about 38$ to try it out - anyhow it's cheap - so I thought "I might give it a go." - doesn't matter, and it's nice - consider it a review (but not perfect, not a professional solution anyway (you draw on one place and the result comes on the other (monitor) - that's unnatural (just like a mouse)...) - but, that's a tablet), it gives some good results, it's prety much precise - no worries about that whatsoever (also is pressure sensitive (1024 levels of pressure - the utility program says)) - you must start from somewhere and this (a tablet) is a good way to do so - definitely; you just need to allow some time to adapt to the technique - to get use to it (I even tried to put a piece of paper on a tablet's surface (because the surface itself is slipery), and achieved better results when drawing (more control over pen (and because paper is a little bit elevated from the tablet's surface you can feel when it's about to touch the surface (which means: less probability to incidently touch it, which is equal to the left mouse button action))), but I would't recomend paper, because (I don't know) it may damage the pen tip (there's more friction with a paper)).
(It's strange at the begining: few times I automaticaly tried that mouse movement routine ("lift-moveback-rollagain" routine you do so you don't "drive" mouse across the surface and have to lift your wrist of the surface), forgetting that tablet doesn't work that way, and also at the begining it requires some attention to actually click the button on the pen (separate keys on tablet or keyboard suppement keys would be a nice option...))
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But, let's talk light-pen.
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