In the early morning when I drove to the gate of a government facility, the sky was still dark. I stopped my car at the gate and raised my badge for the security guard to check. Many times I found the guard had difficulty seeing my badge because my car's headlights were bright while inside my car was relatively dark. I did not know if he really could compare the picture with my face or just “if it looks like a badge, it is a badge.” On the other hand, sometimes when the guard was standing at a dark spot, he might have a better chance to see me but I had difficulty to see the guard's signal to pass. The guards might be from different branch of military and had different ways of signaling to pass. When several cars were waiting in line, it was a difficult time. How can we make the guard's job a little easier?
An “Easy” Solution:
One easy way to solve the problem is to use multiple kilo watts lights shining the gate like in daylight. But it obviously will not meet the “green” requirement for the government. Besides, when I drive away from the extreme bright area, my eyes need time to adjust to the darkness again. That is not good for driving safety.
I have invented a device (US patent 8899656) for night time headlight glare reduction which can be used for security guard post directly. It is based on borrowed concepts from cell phone technology such as TDMA and CDMA. Basically, it consists of a pulsed LED light at a low duty cycle to shine on the car driver and a light shutter goggle for the guard to wear which is synchronized to the LED. Because of the low duty cycle, the goggle will be dark most of the time reducing the intensity of all light except the synchronized LED. We can also use a LED to shine on the guard such that it is on only when the goggle is dark. The guard will see the badge brighter and the headlight darker while the driver can see the guard's signal clearly. This way, the security at the gate is improved.
Advantage of My Solution:
It will enable the guard to see driver's badge clearly without the interference of headlights. At the same time, the guard himself can be well illuminated so the driver can see his signal clearly.
In the threat of terrorism in the world, we need to pay extra attention to security of our government facilities.
I have a patent (issue date 12/02/2014) and have built a MVP (Minimal Viable Prototype) to show the device working. Because in this case the cars are not moving (or moving very slowly), the clock speed can be slower and the parts are cheaper and more available. Full commercial product can be procured in a short period of time.