[simpits-tech] Re: HUD question

[Gene Buckle]

> > It's a function of the lenses.  If you try to actuall focus on the
> > lettering that shows up in the combining glass, it will be blurry.
> 
> ....and double? Your eyes are forming the base of a triangle with the object
> in focus being the third point. If you insert a piece of glass between you
> and the object for the purpose of projecting an image onto the object,
> wouldn't the image have to appear over each line extending from the object
> to each eye (obviously blurred due to the focal distance requried)?
> 
> I fear I'm being 'blined' by something fairly obvious here...
> 
> Is a single lense (assembly - I'm simplifying here) capable of creating this
> illusion? or does the image have to be split somehow?
> 
It's not just a single lens.  There are two lenses (at least) involved
here.  I wish I could give you more detail as to how a real HUD is built,
but I'm _not_ gonna tear down my A7 HUD. :)  The parts listed on the site
I posted the link to yesterday are probably cheap enough for you to bang
out a prototype to answer your own question.  (and that of the rest of
us! ) *grin*  My knowledge of how optics really operate is quite poor.  I
can only make some educated guesses based on how I see it operate.

g.