Illumination system adapted for surgical lighting

An illumination system arranged to mix the output from two separate light sources, said system comprising:

• first and second light sources;
• a first fiber bundle having an input end arranged to receive light emitted by the first light source;
• a second fiber bundle having an input end arranged to receive light emitted by the second light source
• wherein the output ends of the fibers forming the first and second fiber bundles form a single fiber bundle arranged to transmit light from both the first and second light sources;
• and
• an optical homogenizer having an input end arranged to receive light from said single fiber bundle and an output end which delivers a substantially uniform light output.

An illumination system arranged to mix the output from two separate light sources and to control at least one parameter of the mixed output, said illumination system comprising:

• a first light source arranged to emit light having a first characteristic value;
• a second light source arranged to emit light having a second characteristic value differing from the first characteristic value;
• a light mixing means arranged to receive light emitted from the first and second light sources and to produce a light output having a third characteristic value differing from the first and second characteristic values;
• a light detector arranged to receive part of the light output from the light mixing means and to determine said third characteristic value of said light output;
• and
• intensity control means arranged to vary the intensity of the light output from at least one of the first and second light sources and thereby to vary said third characteristic value of said light output from said light mixing means, said intensity control means being controlled by said light detector.

A rotatable fiber joint for use in an illumination system, said joint comprising:

• a first member having walls defining a first passage extending therethrough;
• a second member disposed adjacent the first member and having walls defining a second passage extending therethrough, one end of said second passage being disposed adjacent one end of said first passage;
• and
• a fiber optic bundle disposed within said first and second passages, the bundle being secured relative to the second member so that the bundle cannot rotate within said second passage, but not being secured to the first member so that the bundle can rotate freely within said first passage, whereby the first and second members can rotate relative to each other.

A lighting head for use in an illumination system, said lighting head comprising:

• input means for introducing light into the lighting head;
• a first reflector arranged to receive light entering the lighting head through said input means and to reflect this light, said first reflector being substantially frusto-pyramidal in shape, being provided around its periphery with a plurality of facets each of which is concave in both azimuths, said input means being arranged to produce a plurality of beams each directed at one of said facets;
• and
• a second reflector having a plurality of facets, the second reflector being arranged to receive light reflected from the first reflector and to reflect this light to produce a substantially uniform illumination over a target area.

An illumination system in which a single input light flux is distributed among a plurality of output fiber bundles or light pipes, said illumination system comprising:

• light input means arranged to supply a single beam of light;
• at least first and second light output means each comprising a fiber optic bundle or light pipe, the first and second light output means being movable relative to one another and to the light input means;
• and
• a light distribution means arranged to receive light from the light input means, to divert a first part of the received light into the first light output means and to divert a second part of the received light into the second light output means, said light distribution means comprising a substantially cylindrical fiber optic bundle, and said first and second light output means being arranged to rotate about the axis of said substantially cylindrical fiber optic bundle.

An illumination system in which a single input light flux is distributed among a plurality of output fiber bundles or light pipes, said illumination system comprising:

• light input means arranged to supply a single beam of light;
• at least first and second light output means each comprising a fiber optic bundle or light pipe, the first and second light output means being movable relative to one another and to the light input means;
• and
• a light distribution means arranged to receive light from the light input means, to divert a first part of the received light into the first light output means and to divert a second part of the received light into the second light output means,
• wherein said light distribution means comprises:
• a first light pipe rotatable relative to, and having an input end arranged to receive light from, said light input means, said first light pipe having an output end through which light leaves said first light pipe, said first light pipe also having a mirrored surface arranged to divert part of the light entering said input end through a side wall of said first light pipe into said first light output means, while permitting the remainder of the light to leave via said output end;
• and
• a second light pipe rotatable relative to said first light pipe, said second light pipe having an input end arranged to receive light from said output end of said first light pipe and an output end arranged to direct light into said second light output means.

An illumination system comprising:

• a first light transmission device selected from the group consisting of light pipes and fiber optic bundles, the first light transmission device having an input end and an output end;
• a second light transmission device selected from the group consisting of light pipes and fiber optic bundles, the second light transmission device having an input end and an output end, the input end of the second light transmission device being disposed adjacent the output end of the first light transmission device;
• and
• variable aperture means disposed between the output end of the first light transmission device and the input end of the second light transmission device, the variable aperture means being variable to block a varying portion of the light leaving the output end of the first light transmission device from reaching the input end of the second light transmission device, and thereby controlling the intensity of the light leaving the output end of the second light transmission device.

A coupling device for coupling light from a high intensity light source into optic fibers which can be damaged by heat, said coupling device comprising:

• a window arranged to receive light from the light source, the window reflecting at least part of infra-red radiation received from the light source;
• optic fibers having input ends disposed adjacent the window so as to receive light passing through the window;
• and
• a heat dissipating means in heat conducting relationship with the input ends of the optic fibers, and thereby serving to remove from said input ends heat generated with said input ends as said input ends receive light passing through the window.

An illumination system for illuminating an area within a room, said illumination system comprising:

• at least one light source disposed outside the room;
• at least one lighting device disposed within the room and arranged to output light to said area to be illuminated;
• at least one light pipe and/or fiber bundle arranged to transmit light from said at least one light source to said at least one lighting device;
• means for controlling the intensity of the light output from said at least one lighting device;
• and
• means for controlling the color rendering index of the light output from said at least one lighting device.