Firing a Laser Gun at Fish: Aiming with Light Refraction

Thread starter SissyQ19
Start date Dec 3, 2004
Tags

Light Refraction

Dec 3, 2004

SissyQ19

if you were to hit a fish with a laser gun, how would you aim? (provided that laser if faster than light). Pls explain.

Science news on Phys.org

Research team improves fuel cell durability with fatigue-resistant membranes
Apex predators not a quick fix for restoring ecosystems, 20-year study finds
Building images photon-by-photon to increase the information content provided by microscopes

Dec 4, 2004

krab

Science Advisor

Laser is fster than light? Pls explain.

Thread 'A quartet of epi-illumination methods'

Well, it took almost 20 years (!!!), but I finally obtained a set of epi-phase microscope objectives (Zeiss). The principles of epi-phase contrast is nearly identical to transillumination phase contrast, but the phase ring is a 1/8 wave retarder rather than a 1/4 wave retarder (because with epi-illumination, the light passes through the ring twice). This method was popular only for a very short period of time before epi-DIC (differential interference contrast) became widely available. So...

View full post »

Thread 'Effective absorption coefficient of gold nanoparticles'

I am currently undertaking a research internship where I am modelling the heating of silicon wafers with a 515 nm femtosecond laser. In order to increase the absorption of the laser into the oxide layer on top of the wafer it was suggested we use gold nanoparticles. I was tasked with modelling the optical properties of a 5nm gold nanoparticle, in particular the absorption cross section, using COMSOL Multiphysics. My model seems to be getting correct values for the absorption coefficient and...

View full post »