7. Conclusion

Our (non-exhaustive) review of the various processes for reproducing cinematographic images on the big screen has enabled us to summarize the characteristics of special formats and trace their technical evolution. The development and refinement of projection systems have been conditioned much more by advances in light sources than by mechanical advances in projection equipment (most of which use multiple projection and/or horizontal image scrolling). Increased light output and improved optical systems have enabled images to be projected onto ever larger screens.

By 1995, the majority of large French cinemas were equipped with xenon projectors, whose power can reach 500 W for small cinemas and up to 7 kW for very large cinemas, whereas an Imax or Omnimax projection requires the use of a 15 kW xenon lamp (or two lamps in the case of 3D projection). The French company...