Low-bulk optical collimator for generating a small spot of illumination

A surgical lighting device forming an illumination spot, comprising:

• a lighting dome having a plurality of lighting devices,
• wherein each lighting device includes a solid optical collimator comprising a truncated cap having an inside surface operating in total internal reflection and having a small base opening into a frustoconical through recess that is coaxial with said cap and at the centre of which a light source is placed, and having a refractive large base such that incident light emitted by said light source is guided in totality by said inside surface towards said large base of said cap, and
• wherein said recess of said collimator is disposed in said cap in such a manner as to have a small base open and coinciding with said small base of said cap, and in that said collimators are directed to concentrate the light flux from said light sources onto said illumination spot that is centered on the illumination axis of said lighting dome.