Category Archives: optics

Spy Camera Math

Introduction I just listened to a very interesting interview of Philip Pressel, a retired Perkin-Elmer mechanical engineer and satellite surveillance camera designer. The interview was conducted by Vince Houghton of the International Spy Museum. Philip discussed how the recently declassified … Continue reading

Posted in History of Science and Technology, optics | 3 Comments

Optical Power Budgets and A Quick Dispersion Calculation

For those who are not familiar with dispersion, take a look at Figure 1, which provides a qualitative view of dispersion. The digital data can be view as a stream of optical power pulses, ones being represented by power and zeros represented by near zero power. The pulses of optical power can be viewed as composed of a range of wavelengths (i.e. color). The different colors all move at different speeds along the fiber. This speed difference causes the pulse to spread out as it travels down the fiber. As the pulses spread out, they begin to overlap each other and their power levels reduce. This makes detection less reliable and is one of the fiber impairments that limits the range and data rate of optical fiber. Continue reading

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The Biggest Ball Lens I have Ever Seen

Quote of the Day The most important thing in the world today is that England and the United States speak the same language. — Otto Von Bismarck We use tiny ball lenses all the time to mate our fibers up … Continue reading

Posted in Fiber Optics, General Science, optics | Comments Off on The Biggest Ball Lens I have Ever Seen

Mathcad Example Using Decibels

Quote of the Day I learned filmmaking by studying the Old Masters - and by that I mean John Ford, John Ford and John Ford. — Orson Welles Introduction I have been working on a software requirements document that involves … Continue reading

Posted in General Mathematics, optics | 7 Comments

Battleship Rangefinders and Geometry

Quote of the Day Russia is a riddle wrapped in a mystery inside an enigma. — Winston Churchill. Introduction While reading a web page on WW2 naval warfare, I found some interesting material on how naval gunfire was spotted -- … Continue reading

Posted in Naval History, optics | 19 Comments

Distance to the Horizon Assuming Refraction

While doing some reading on lighthouses, I needed a formula to compute the distance to the horizon as a function of height. This formula would give me an idea of how far away a lighthouse could be seen. Continue reading

Posted in General Science, Navigation, optics | 26 Comments