intervoxel said:How can a mirror reflect 99,999% of incident light? Or in other words what makes a photon exiting a laser cavity so directional?
In fact, I never found a really convincing answer. Thank you.
Nice answer, ZapperZ. Let's suppose now one single photon with the correct wave length to get maximum reflection. What happens to the properties of the photon to have higher probability of detection in a very closed angle cone in the direction of reflection?ZapperZ said:Your question is vague. No mirror can reflect ALL wavelengths at 99.999% efficiency. The regular mirror that you and I are used to may appear to be a good reflector of visible light, but put that in a UV-VIS spectrometer, and you'd be surprised at reflectivity spectrum, even in the visible range. And forget about UV, because such a mirror is hopeless.
Mirrors in laser cavity has been specifically selected so that it has the highest reflectivity in a very narrow range of wavelengths. So it has been finely tuned to work under a very narrow parameter.
Zz.
intervoxel said:Nice answer, ZapperZ. Let's suppose now one single photon with the correct wave length to get maximum reflection. What happens to the properties of the photon to have higher probability of detection in a very closed angle cone in the direction of reflection?
The reflective surface of a mirror is typically made of a highly polished material, such as glass or metal. This smooth surface allows for the majority of light to be reflected back in a predictable manner, resulting in a high percentage of reflected light.
The material used for the reflective surface, the smoothness and flatness of the surface, and the angle at which the light hits the mirror all play a role in its reflective capabilities. Additionally, the quality of the coating on the mirror can also impact its reflectivity.
No, it is not possible for a mirror to reflect 100% of incident light. Even the most perfectly polished and coated mirrors will still absorb a small amount of light, resulting in less than 100% reflectivity.
Yes, the reflectivity of a mirror can change over time due to factors such as dust, dirt, and scratches on the surface. It is important to regularly clean and maintain mirrors to ensure optimal reflectivity.
Yes, there are limitations to a mirror's ability to reflect light. The angle at which the light hits the mirror, the quality of the coating, and the material used for the reflective surface can all impact the maximum percentage of light that can be reflected.