Crosstalk reduction in film player

Claim 1

In a television system, optical apparatus for momentarily projecting onto a camera tube during vertical blanking intervals light from a stroboscopic light source through successively image-bearing frames of a continuously moving motion picture film also having, in a marginal strip adjacent said image-bearing frames, recorded information including synchronizing indicia related to said respectively adjacent frames, said optical apparatus comprising: a series arrangement in a main light transmission path from said stroboscopic light source to said camera tube of a first dichroic mirror, said film and a second dichroic mirror, both of said dichroic mirrors being angularly positioned relative to said main light transmission path and functioning (1) to direct light of a first color emanating from said stroboscopic light source forwardly along said main light transmission path to said camera tube and (2) to direct light of a second color backwardly along that part of said main light transmission path between said mirrors and also along first and second auxiliary light transmission paths branching respectively from said mirrors; photodetecting means located in said first auxiliary light transmission path adjacent said first dichroic mirror and responsive to light of said second color received from said first dichroic mirror and representative of said synchronizing indicia to develop triggering pulses for momentarily actuating said stroboscopic light source to produce short duration flashes of light of said first color for forward projection through said image-bearing frames of said film; and light producing means located in said second auxiliary light transmission path adjacent said second dichroic mirror for continuously supplying light of said second color to said second dichroic mirror for backward projection through said marginal strip-recorded information of said film and for direction by said first dichroic mirror onto said photodetecting means.