Measuring the reflectance of a surface?

[Lostman11]

Guys, was hoping to get some feedback on a measurement of reflectance I was hoping to conduct.
Generally in published work I see that reflectance is plotted vs. wavelength, and most of these measurements are done with equipment such as integrating spheres etc for diffuse reflection etc.

I don't have access to all this equipment, I have a laser of λ and a power meter/detector, and I actually would be more interested in measuring reflectance as a function of angle of incidence. (surface is silicon something, so I would be measuring specular reflection here)

My plan was to place sample on rotational stage, measure power using power meter before sample and then after reflection. Couple of questions on this...

1) Would this work? and would this actually give me a reflectance vs angle of incidence curve I am aiming for?
2) Just to throw out some numbers; say the power before sample was 100mW and power after 10⁰ incidence is 95mW. Does this mean that reflectance is 95% at 10⁰ for given λ?
3) If yes, from fresnel equations is this then a percentage of R as opposed to r?

Thanks

 

[Valerie Park]

a lot in advance.Yes, this should work and should give you the reflectance vs angle of incidence curve. The percentage of reflectance you get will depend on the angle of incidence and the wavelength, as well as the material properties of the surface. The Fresnel equations will give you the reflection coefficients for the various angles of incidence, which you can then use to calculate the reflectance.