THE nature of the distribution of light round the axial focus of a lens is a problem which has frequently been attacked mathematically. It has been quite successfully solyed for points in the ...

ABSTRACT: With cataract surgery entering the era of refractive cataract surgery, people’s requirements for visual quality are getting higher and higher. From “visible” to “clear” and then to ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Thomas J. Brock is a CFA and CPA with more ...

Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...