Linda was heading out west on Hy80 again.  She was getting tense about the coming night; Two hours of her shift are after sunset now and night time driving was bothering her more and more.  The highway made a turn SouthWest and her brooding was rudely stopped.  Her hand shot up to protect her eyes from the blinding light of the sunset.  She struggles  to keep the 18 wheels in the lane.  Fortunately she is already used to the knob on her new Mack's steering.  But she has to switch hands to shift gears.  Linda looks to the side to be able to see anything in the glare.  So when finally in 6th gear, she is happy to put up her right hand to block the sun.  Steering left handed is awkward but she has done it before, when the kids were acting up back then in the old car.  Earlier she had the visor down, but it is useless now!  After 2 or 3 minutes she switches hands again.  Then Linda is glad to see her next turn. Able to see again she starts to relax but needs to make a stop.  She pulls into a small diner.  After a 10 she reluctantly returns to work.  As she pulls out of the mall, she is again blinded; Its an SUV with badly aligned headlights.  It stops and waits for the 18 wheeler. But its lights are directly on her cab until she nearly passes it.  Fortunately she is dead-heading, so the Mac accelerates faster.  She misses the lane and the trailer bounces over the center divide.  Linda's tension is back!  She hoped the break would keep her headaches away, but it doesn't.  The throbbing is back again tonight!  She is glad she has arranged to see a doctor the next afternoon;  She also gets a night off.
After the exam, the doc has good news.  There is nothing wrong with her that rest would not cure.  He gives her a muscle relaxant.  She has to work and driving is the only thing she knows and loves; so the doctor suggests an Optometrist.  He works at the university hospital and might be able to help reduce her stress from night driving.  At the Optometrist's  office, Linda winces at the bright light.  The doc announces that she has 20/55 and 20/25 vision: She needs glasses.  Linda picks out a large frame.  He says that one will be costly;  she doesn't care. "I am worth it! And this helps my poor vision." He suggests an anti-reflective coating will reduce the glare.  So she tries a sample lens; It does not help her.  He then says he is working with a new product that cuts out glare electronically.  It is called SunSpot.  He is confident it will help, so Linda is excited.  Her boss gives her a half day off to try it.  The doctor has a pair he can fit for her.  They are not very stylish but neither was the ordinary pair Linda had picked out.  Her company paid ¾ the cost of the electronic glasses and Linda is much more relaxed driving now day and night!
The SunSpot glasses are under development by Sunspot Systems in Redmond, WA. These so called electronic dark glasses are not really dark at all!  Only a small spot is darkened when needed to shade the eye.  The spot or spots on the lens show up whenever needed to block bright lights from getting in your eyes.  The rest of the lens stays clear so you have perfect vision at night or in deep shadows.  In this story, Linda no longer has problems driving at sunset and sunrise or when approaching cars have those super bright Halogen headlights.  It does not batter any more if they are on high or low beam.  The SunSpot covers the situation with just the right spot.  The dark spots are quickly removed also!  The SunSpot system relies on a micro-processor to watch the view from a camera on the glasses.  Whenever a predetermined brightness is reached the appropriate part of the lens is activated by a short burst from the tiny battery.  New nanotechnology processes have produced a composite of polymer films. This has an electrocromic layer which responds by changing opacity when nudged by a 4.5 volt burst.  At present one inch spots are possible.  With funding for this project a local university professor says he can product 15 spots on a glasses lens within 6 months.  The base can be of most any material that can withstand moderate heating; glass, polycarbonate, plastics, etc.
The resulting smart material is clear, very light-weight, high-contrast, and requires very low power compared to LCD materials which ordinarily use micro-transistor technologies.  It is also very inexpensive to produce, comparatively.  It speed and durability need to be improved to be a big seller for glasses.  Sunspot Systems expects to be producing limited quantities of glasses (with and without prescriptions) within a year of the first prototype.  Many prototypes will be produced and tested (in house and in the field) to determine best parameters to reduce stress and glare.
How before sunset Linda always turns ON her SunSpot glasses.