Matching optics for Gaussian beams

A system of matching optics for Gaussian beams is described. The matching optics system is positioned between a light beam emitter (such as a laser) and the input optics of a second optics system whereby the output from the light beam emitter is converted into an optimum input for the succeeding parts of the second optical system. The matching optics arrangement includes the combination of a light beam emitter, such as a laser with a movable afocal lens pair (telescope) and a single movable lens placed in the laser's output beam. The single movable lens serves as an input to the telescope. If desired, a second lens, which may be fixed, is positioned in the beam before the adjustable lens to serve as an input processor to the movable lens. The system provides the ability to choose waist diameter and position independently and achieve the desired values with two simple adjustments not requiring iteration

Transcript of Bernie’s Final Tuna Run

This story is an excerpt from a longer interview that was collected as part of the Launching through the Surf: The Dory Fleet of Pacific City project. In this story, Bill Hook recounts the experience of spreading his stepfather’s ashes on the tuna grounds

High office requires high standards

Historical series, 2. Delivered at Yorkminster Baptist Church, Toronto, Ja 6 1994

Heroes of Berlin Wall Struggle

When the Berlin Wall fell 25 years ago, on Nov. 9, 1989, symbolically signaling the end of the Cold War, it was no surprise that many credited President Ronald Reagan and Soviet leader Mikhail Gorbachev for bringing it down. But the true heroes behind the fall of the Berlin Wall are those Eastern Europeans whose protests and political pressure started chipping away at the wall years before. East German citizens from a variety of political backgrounds and occupations risked their freedom in protests against communist policies and one-party rule in what they called the peaceful revolution. [excerpt

Non-vanishing of Dirichlet series without Euler products

We give a new proof that the Riemann zeta function is nonzero in the half-plane $\{s\in{\mathbb C}:\sigma>1\}$. A novel feature of this proof is that it makes no use of the Euler product for $\zeta(s)$.Comment: 13 pages; some minor edits of the previous versio