Re: Lena's Birthday Question: Neatest Optical Hacks

In article <442D6CF2.7090504@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
Phil Hobbs <pcdh@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

Yes, folks, that's right! Once again, this Friday (March 31) is the
birthday of Lena Sjooblom, the November 1972 Playboy model whose face
is
so familiar from so many bad image processing papers.


Not sure what you do and don't consider a "hack" but here are a few:
(Why don't you annotate 'em, yes or no, as to whether they make the
grade)


* Student in my lab who got the CO2 gas supply he needed for an early
home-brew CO2 laser by squirting it from the hallway fire extinguisher
into a plastic laundry bag. (Fire marshall was not happy at next safety
inspection.)


* Student in my lab who triggered the spiral flashlamp in his very
early home-brew ruby laser using a Ford Falcon spark coil.


* CO2 lasers using water-cooled distillation columns bought from
chemistry supply houses as the laser tubes -- and evaporated-gold-coated
eyeglass lenses for the mirrors.


* Revitalizing early Spectra Physics and other He-Ne lasers that had
lost their He due to out-diffusion through the glass envelope by putting
'em in a plastic bag filled with 1 atm of He overnight.


* The very early low-cost internal-mirror He-Ne lasers made by
University Labs in Berkeley using chem lab beakers (with the "100 ml,
200 ml" markings still visible on them) as the bells for the laser
structure. (Marketing manager -- or one of the management positions --
for the firm was Tom Perkins, later co-founder of mega-billion venture
capital firm Kleiner Perkins.)


* Art Schawlow and Ted Haensch's edible dye laser: ". . . The laser
material was colored Knox gelatine, prepared according to the directions
on the package . . .as such, the material was a bit soft for optical
work."


* Gouy demonstrating the 180 degree Gouy phase shift through a focus
experimentally in 1890, at a time when knowledge of wave propagation was
still in very early stages.


* Israeli CO2 gasdynamic laser made by igniting a gasoline mixture
inside a heavy-walled tank (using an ordinary spark plug to do so);
blowing open a heavy spring-loaded exit door; and letting the gas exit
through a supersonic noxxle.


* Russian very high power quasi cw CO2 gasdynamic laser, apparently
used for heat treatment of steel, made by filling an ring of big
(house-sized) heavy-walled tanks with CO2; heating them up to just under
bursting pressure using gas flames (huge Bunsen burners!); and
sequentially valving them, one after another, into a supersonic
gasdynamic laser, while previously used tanks are refilled and re-heated.


* And also


* As a follow-on to rotating mercury mirrors (which I would have cited
also), Roger Angel at UoA making deeply curved, near optically perfect,
3 or 4 meter diameter mirrors by electrically melting several tons of
glass in a backyard swimming pool sized tank supported 8 feet up in the
air on huge rotating megatwatt-capacity electrical contact bearings;
then rotating the tank for days on end while the glass cooled.


* And, in same project, making the mirror lightweight by having
sandstone posts which don't melt forming a honeycomb structure inside
the meter-thick (or thereabouts) mirror blank after the glass melts;
then blasting these out with high-pressure water after the mirror cools.


* Using ink-jet printing technology to fabricate nanotech parts or
printed circuits.


* The guy at Berkeley (??) who floats tiny GaAs tetrahedrons into
pre-etched, properly shaped pits on silicon wafers using water, then
makes 'em operate as EO devices.


* The early fiber optics guy described in Jeff Hecht's excellent book
"City of Light: The Story of Fiber Optics" who drew glass fibers many
tens of meters long by attaching the tip of a softened glass rod to a
metal bolt and firing it down the length of a hallway using a cross bow.


* British researches described in same book who demonstrated how to
fabricate clad fibers using a central nozzle connected to one crucible
and a concentric nozzle connected to another -- with colored and clear
molten sugars as the (much more easily melted) core and cladding
materials.


* Early Bell Labs White cell experiment where they broke the x,y
symmetry of the cell, and thus were able to get many more bounces
stuffed into the cell, by mechncially bending one of the end mirrors.


* Allied Chemical, who found it very difficult to separate the mixture
of rare earths used to add luminosity to Coleman lantern mantels, so
just packaged them all in one powder and marketed it as previously
unknown rare earth "dydimium".


* The old idea of compensating thermal expansion by using a
differential structure where short section of high-expansion material
compensates longer section of lower-expanson material.


* Which leads to whole idea of precision differential screw techniques
using slightly different threads per inch.


Enough for today -- I'll see what occurs to me in the midnight hours
tonight.
.

Relevant Pages

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