well? I hear nothing but “crickets chirping”. I might well be once again talking to the walls, which annoys my cat. But, just in case…
quick recap? our paradox has been stated in mathematical concrete terms. we KNOW the pre-collimated lights exist, examples of them have been shown. I myself have built two of them, but in infrared. a long process of “hand tuning” 4 lenses interacting with each other? working invisible infrared? is “maddening” to say the least. notwithstanding, the only way io can MAKE them? is both times with… the lenses from three gun scopes all tore apart, and also one spotting scope not made anymore. and the long hand tuning process.
vinz made them, the violin maker has one… bigfoot exists. And once you have SEEN the emitter get bigger AND brighter,instead of bigger and more dim like it should? you are HOOKED like CRACK.
i dont think these people are “calculating” it? i THINK they did what i did… noticed it during long “hand tuning” and capitalized on it. BUT, thats my guess. Either way? none of them are forthcoming, exactly “what” to buy and “what” to exactly DO to replicate the results.
this engineering paper i am referencing? which no one will read? immediately moves on to “step two” which they entitled “using lens PAIRS”…
QUOTE
2 Aspheric lens pairs
A second aspheric lens can be added in front of the collimating lens to focus the
light over a desired area. The illuminated spot diameter at the focal plane (FP) is
given by
ENDQUOTE
SpotDiameter = Ds * (F-foc / F-col)
Ds = diameter of the source LED
F-foc = focal length of the focusing lens
F-col = focal length of the collimating LED
===
they immediately follow this with I_N_S_T_R_U_C_T_I_O_N_S of what to do, and to select lens pairs! to wit:
By selecting the focal length of the focus-
ing lens to be longer than that of the
collimating lens, it is possible to reduce
the numerical aperture to below that of
the source (NAbeam). For distances greater than f focus, the full
beam divergence (θ’) in radians becomes:
THETAprime = 2 * NAbeam * (F-col / F-foc)
THETAprime = full beam divergence (expressed in radians)
2 = “the number two”
NAbeam = numerical aperture of the beam
F-col = focal length of the collimating lens (inner lens)
F-foc = focal length of the focusing lens (outer lens)
==
Thats it. Nothing else! they merely go on to say that the “limitation” of this? is that the “source structure” of the light source will be projected out, which is a way of saying “you will SEE the emitter” which we all see anyways, big deal.
the whole rest of the paper? has nothing for us, its a bunch of crap to “blur” the light so you cant see the emitter, crap like light pipes and microlens arrays, nothing concerning me.
NOW… this description? they are DESCRIBING the “vinz” pre collimated light! this is the perfect description of the “violin maker build” referenced above. THIS is what i saw happen with “hand tuning” 4 lenses! why did i see it? i know now… my 4 lenses were actually 2 lenses, really… my “rear 2 lenses” were interacting to be the collimating lens, and the “front 2 lenses” were interacting to be the focusing lens!
as i hand tuned the 4 lenses around? i happened onto the “trend” and was able to chase it and maximize it… because my 2 lenses, were each made out of 2-lens-compound lenses with air gaps? moving the lenses around was like selecting different lenses! i didnt have to try hundreds of lens combinations, i had them all available by adjusting airgaps!
do you see?
===
so? for the final ray trace? i would suggest…
a lens with higher focal length, on the outside… and a lens with lower focal length, on the inside in front of the LED.
naturally, i am unsure exactly what the values of the FL’s should be…nor exactly the distances, but…
…isnt that what fooling around with the ray-trace would show? at some point, you would notice “rays” being captured in excess of a single lens??
this isnt “conjecture” on the internet, this is an engineering paper, the exact sort of paper “dr jones” would follow to make something in his lab for whatever company he works for…
its “how” to make the precollimated light. we just need to fiddle with the equation values, and the lens choices. ray trace should show this??
===
lets be “prometheus”. lets steal FIRE from the GODS ? and give it to MAN… lol