Can a light of one light bulb be increased by reflections through a mirror?

Hi Nat,

I hope you choose answers and not just post questions all the time.

Ginger has the best answer by the way.

Before the invention of Electricity, and the use of kerosene, candles were

used. They also used mirrors to concentrate light into a certain area.

So are you coming down to use my holiday house :)

Cheers

Gus

Sure, put the bulb between two parabolic or concave spherical mirrors and the radiation density in the cavity will get quite high. If there is also a gain medium its called a laser. It is also possible to use mirrors to concentrate light emitted by a bulb into a small solid angle. The intensity integrated over 4pi sr will be reduced a bit because of optical losses (mirrors are not 100% reflective in general, but there are exceptions). However the intensity in the bright spot could easily be more than 100X as bright as the bulb. Note that this is usually done with refractive rather than reflective optics.

Yes on the increase of light, I agree with the last response, not the intensity.

You may find it interesting that many kerosene lamps used before electricity was available often had small mirrors, or some type of reflectors attached.

I've also seen this concept used in the same time period to increase light in medical procedures. ( in photos)

Some light will be lost each time it is reflected.

Mirrors can, however, be used to concentrate the light to a smaller area. That will appear brighter.

no.