Archive for January, 2010


January 28, 2010

I knew that the ultimate package would be one that would not involve any cables or wires, or a big controller the size of a hi-fi amplifier.  But how to fit everything into a pair of eyewear??  There were some big stumbling blocks.  We couldn’t get a high enough dynamic range out of a single cell all by itself.  If we had to stack two of these shutters together, as we did in our headband visor, we would be using more power and have more weight.  Not good for wireless battery powered eyewear.  (more…)


January 27, 2010

CrystalEyes may turn out to be one of the most important products of the last few decades.  It’s self-serving to say so because I am the primary inventor of CrystalEyes and shuttering eyewear that may be the basis for 3D TV image selection.  The basic concept of shuttering eyewear for viewing stereoscopic images isn’t mine.  You can find mentions of it in the literature before my work began.  Missing from the early work were the elegant electro-optical shutters that we now have and a good communications link between the display and the eyewear. When CrystalEyes was designed in the mid-1980s infrared links were advanced and a good way to communicate between the video source and the eyewear.  Today you might also consider using Bluetooth or some other form of radio. (more…)


January 19, 2010

I went to school with Mel Siegel, a physisist at Carnegie Mellon.  I asked Mel for a simple explanation of polarized light in terms of quantum theory.  In this case that’s the construct that light can be explained in terms of it being a particle — a photon.  Here’s what he wrote: (more…)


January 18, 2010

If you take a left- and right-handed circular polarizer and you lay them on top of each other on a light box, you will see that they will extinguish the light.  Do the experiment by using the filters from a pair of glasses from a MasterImage or a Real D show and put the polarizers together so that the retarders are facing each other (those are the sides of the filters that are facing the screen). If you rotate one with respect to the other you will see that the extinction varies.  What’s going on here?  It’s circularly polarized light and you would think that you wouldn’t get a variation in extinction as you do for linear.  But you do get a variation and you will see that the image will go from pretty dark to, depending upon the material you’ve got, a sort of amber color that transmits more light. There is quite a noticeable variation in both density and color with rotation. So the head orientation does matter, except that the falloff isn’t as great as it is for linear polarized light. (You can also hold the filters sandwich up to a light source – like a desk lamp.) If you flip the filters around the other way so the retarders are facing outward you have linear polarizers and you can try rotating them to confirm that they work as described earlier. You will note that even for the circular case you perceive the extinction to be at a maximum when the linear axes components’ are at right angles.  (more…)


January 15, 2010

A large percentage of light passes through when the filter’s axes are parallel and this is called transmission, and a smaller percentage of light passes through when the axes are at right angles and this is called extinction.  The ratio of the two is called the contrast ratio or the dynamic range.  For good linear (or as I said earlier, some people call it plane) sheet polarizers for stereoscopic applications, the materials used usually have transmission between 30 to 35 percent and the dynamic range is about 3000:1 for the lower transmission material. In other words, only 1/3000th of the light in transmission passes through when the axes of the polarizers are orthogonal (extinction).  For circular polarization the dynamic range is about a tenth of that for good linears.  (more…)


January 13, 2010

From the time I was kid to my student days as an undergraduate in physics my abiding passion was light and vision.  Since my earliest years I have been interested in creating images and in understanding the role that light plays in image creation.  As a student no other part of physics engaged me as much as the study of light.  (more…)


January 1, 2010

Touching history.


 I staggered off the Air France flight from Los Angeles to Charles de Gaulle Airport and I fell into the arms of Bernard Benoliel and Laurent Mannoni of the Cinémathèque Française and into their waiting taxicab.  Off we went through the streets of Paris – a grand blur – having had only a few hours of sleep in the past day,.  I’d like to be a really good traveler, but there is nothing I can do to hide the terror – or maybe, as Kurtz said, the horror.  Flying in a metal cylinder at 36,000 feet requires surrendering complete control to the pilot and the guys who designed the airplane – which is not necessarily easy to do, especially if you think about all the things that could possibly go wrong.  The bright side is that death would be instantaneous.  And the security measures at the airport are aggravating and not adequate, as has been lately demonstrated. But sitting there in the airplane, even if you’re in Business Class, leaves you feeling one-down because the guys in front of you are in First Class where it’s really comfortable.  (But of course there is the ultra-secret first class-plus that the first class passengers envy.) Business Class is a lot better than sitting in the cattle car.  At least the seats aren’t chipped and everything works, more or less.   (more…)