This should work

Sure. but you have to average the intensity over the whole area, so a single bright spotlight can be spun to light a whole room, but at a lesser level of illumination.

A very good and succinct answer. Bravo!

Sure, a lesser level of intensity, but if it spun fast enough, would a person standing there notice a difference. as in, if the light had a 360 degree view, the light intensity would certainly be less than if the light were set up as a spot light, in a particular direction. but if a very shiny "chrome half dome, with the light emmited at the back side and top all reflected like a spot light, with the rotation at a very high speed, would an observer percieve the intensity as greater than just a simple 360 degree view? (ignore the fact that it would take more energy to rotate the top than just put in a larger bulb).

DavidARheault

If the rotating light on the top of a police car went around fast enough it would light up the whole area.

In first term I agree with Bhankii.

There is another issue: this light would probably flicker a lot making it not comfortable for the persons exposed to it.

Flickering will also cause seizures on epileptic persons due to a phenomenon called photostimulation (to which epileptics are very sensible to)

It depends on the rate of rotation. Most people can't see a flicker of less than 16 Hz. Compare the use of a single laser beam and mirrors to create the illusion of a flicker-free field of light.

It depends on the rate of rotation. Most people can't see a flicker of less than 16 Hz. Compare the use of a single laser beam and mirrors to create the illusion of a flicker-free field of light.

Is that a stationary light source? 16Hz seems like a very low number considering the number of people that can see flicker in a 60Hz monitor. If a 16Hz light source like an LED which turns on nearly instantaneously is in motion, I would argue that most people would be able to tell it is flashing.

No one is talking about a rotating blinking light. I can certainly see the blinking LEDs on my bike tires as discrete arcs when I ride. The point is simply that, if you rotate the light fast enough, it will look like quiet, uniform illumination, with no movement or flickering. Whether that means 16 rpm, or 1600 rpm, I couldn't say, never having researched it.

Hi bhankii,

I once had the idea to use a single bulb to light multiple rooms. The light did not rotate as the topic poster suggested but instead it would be mounted in the attic in a central location. A rotatable parabolic reflector would focus the light onto a 45º mirror which would reflect the light downward into, say, the living room through a hole in the ceiling. Now, if you wanted light in the bedroom, you would have your controller rotate the reflector to aim the beam toward a 45º mirror above the bedroom then down through a hole. Of course this design assumes you want light in one room at a time which, granted, is not very practical. However, if properly designed it could possible be an energy saving device. One bulb to do the job of multiple bulbs.

I never built a prototype but maybe you (and/or the rest of you guys) might have some "reflections" on the idea.

John

There is another issue: this light would probably flicker a lot making it not comfortable for the persons exposed to it.

Yeah, I get uncomfortable seeing it rotate at any rate!

interesting!!

Do you know our lamp is powered by a AC power which change its direction every time? if you use a photoelectric detector you will find its big one time and smaller another time.

do you see news interview( press release), the flash lighting on cameras light whole hole?

you have to calculate the flux of lighting.

if you dont mind it, of cuae you can use one spot light for whole room, when it rotate time to time fast.

I was going to try to explain this but they did a better job here.

Cool!

I need my CRT at 85Hz. LCD can go 72Hz.

My girlfriend still see flicker on the CRT when it max out at 120Hz.

Flickering is worsen when you got different source flickering at slightly different rate. Try to watch TV under fluorescent light.

Good thing with electronic blastlast, fluorescent are almost flicker free now.

Pineapple

A rotating light, actually it's a rotating condenser, on the top of police car will not light up the whole area, no matter how fast it rotates. Instead, it'll light up an annular or ring area. In order to light up the whole area, you need to rotate the condensing lens 2D x 360^o , moving up and down, and side to side, so as to cover the whole area with light spot, and you need to make it rotate fast enough.

Mechanically such an all-way rotating lens might be workable, I am thinking about how much energy it will consume to make the lens work, and why don't just use such a rotating energy to light up a bigger light bulb?

"A rotating light, actually it's a rotating condenser, on the top of police car will not light up the whole area, no matter how fast it rotates. Instead, it'll light up an annular or ring area."

It all depends on how close the walls are.

Also, I think this is probably why they invented the "light Bulb."

The idea was proposed, to explain the theory that light emitted for a very short time, is received by the human eye as light. Thus would it be possible to utilise short periods of light whilst the remaining light is used elsewhere to provide light at another target?

Thus an example of a football field being illuminated using less energy by a series of lenses or mirrors each pointing in different directions whilst the one light was directed to each lens or mirror in turn at speed.

Perhaps someone can utilise the idea.

All of the light can be used else where. The last thing I want is to look directly into a halogen lamp, even for an instant. I just want the light that's bouncing off of stuff.

24 fps seem to do really well at the movies. But 24 flashes per second would be unbearable in a room. Incandescent bulbs, dip in brightness 120 times a second, so do fluorescents, but the affect is more noticeable with the later.

The thing that needs to be researched here is whether it takes more energy to move a spot (plus cost of other equipment) than just using a conventional light.

Also, the original question was really just whether it would work, and not whether it was economically feasible... Ya, know I'm just messin' with you, right?

Hey vermin,

I agree with you that a rotating light is impractical. I think it would just create enormous headaches for the recipient of those flashes unless it rotated extremely fast. Even then, as someone has pointed out, the light output at any point of rotation would be diminished.

What about my idea (post #11) of rotating a parabolic reflector to direct the light as needed. Rotate it only when you wish to change the room to be lighted. The reflector directs the beam horizontally to a 45º mirror which directs it downward through a suitable lens so as to give either a flood, or spot, effect.

OR, OR, how bout this: the bulb in the attic is a grow lamp! Now put the parabolic reflector on a timer to grow-light the tomatoes in the living room then after a preset time redirect the light to grow the marijuana in the bedroom. Brilliant!

Funny how ingenuity interacts with engineering.

Cheers

And it also depends on the way the light rotates. For instance, if I took a conventional police light rotating around what we'll call the z-axis, then rotated that assembly around the x axis, the entire room would be illuminated.

Then, if I rotated that around the y axis, and managed to get all the rotations up to several 10's of thousands of rpms, and used superconducting magnets instead of light bulbs, I could (theoretically) warp the space in the room and bring in light from other dimensions.

Way more fun than just a light bulb.

OK, so now we've accidentally blown the lid off the secret of what CERN is really building the Super Collider for!!!

Have anybody looked at the shaft or coupling between a diesel engine and an alternator in the light of a bulb attached to the alternator? I have heard of some injuries when the coupling was touched.

using AC for the purpose will be out.

The question ask is rather would more light be obtained by rotating a reflector around a bulb opposed to using direct light.

Would the enhanced (reflected + direct) light over a shorter period of time produce overall better visibility?

I think not.

Just as the eye and brain retains the light it will also retain the absence of light.

This may also lead to all sorts of optical-brain effects, like streaks and trails, etc..

I´d rather have a fixed light ... and a rotating room!

The last time I did some stadium lighting was in ±1980. At that stage we had to use 4 banks of lights (150each) with each light focused on a calculated position on the field to obtain an even distribution of light. I can not remember all the detail any more.

The technology did improve over time and it may be possible to have a single unit capable of replacing 5 to 10 bulbs.

The problem with only 15 to 30 bulbs in a bank is that bright and dull spots will be formed. To solve this problem a single bulb may be required to serve 5 to 10 spots by rotating and reflecting.

Therefore no light is gained but the surplus light of the stronger bulb is distributed over a larger area.

Your rotating light may have the advantage that light that may have been lost (up and down) are now reflected towards the target.

I think we've reached an appropriate point in the discussion to trot this one out...

Let's just all wear night-vision goggles and spin around real fast. Wheeeeeee!!!

Don't forget strobing...and the movie wagon wheel effect. Perception of anything in motion could be distorted, slowed, stopped...or mesmerizing. Lotsa fun or bad things could happen.

I concur.