Production of television signals from photographic disc recordings

Abstract

6. In combination in a system for reproducing .Iadd.video .Iaddend.information from a rotatable medium where the medium has characteristics at progressive positions along a spiral path for modifying energy directed at the medium in representation of .Iadd.video .Iaddend.information previously recorded on the medium where the information recorded on the medium at each successive position along the spiral path represents substantially less than a complete visual image, means operatively coupled to the medium for producing a continuous rotation of the medium, pickup means disposed relative to the medium including, means for directing .[.energy.]. .Iadd.a beam of energy having a radius not greater than approximately one micron to enable the reproduction of the video information .Iaddend.at the medium at each instant to obtain a modification of the energy passing from the medium at that instant in accordance with the variations in the characteristics of the medium at the progressive positions along the spiral path, and means responsive to the modified energy at each instant for producing signals having characteristics representative at that instant of the information recorded at the progressive positions along the spiral path on the medium, .[.and.]. means operatively coupled to the pickup means for varying in synchronism at each instant the position of the means for directing energy and the means responsive to the modified energy in a direction having a radial component to obtain a .Iadd.coarse .Iaddend.tracking at each instant of the characteristics at the progressive positions along the spiral path on the medium.Iadd., and means for varying in synchronism at each instant the position of the signal producing means relative to the energy directing means to obtain a fine tracking along the spiral path on the medium. .Iaddend.

What is claimed is: .[. 
     
       1.  In combination for use with a medium having at successive positions variable characteristics representing information recorded on the medium of visual images to obtain the reproduction of such information where the variable characteristics of the medium control the amount of light passing from the medium upon the direction of light toward the medium and where the information recorded on the medium at each successive position represents substantially less than a complete visual image, means for providing a continuous movement of the medium to present the successive positions on the medium for the reproduction of the recorded information,   means disposed on one side of the medium for continuously directing a beam of energy toward the medium at each instant of time to obtain variations in the intensity of the energy at the instant passing from the medium at one of the successive positions in accordance with the characteristics of the medium at that one of the successive positions,   means responsive to the variations in intensity of the beam of energy passing at each instant from the medium at one of the successive positions for converting such energy into signals having characteristics corresponding to the intensity of such energy at that instant, and   means responsive to the energy passing from the medium at each instant for controlling the rate of presenting at that instant the successive positions on the medium for the passage of the energy at that instant to the converting means to obtain an accurate reproduction of the information on the medium..]. .[.2. The combination set forth in claim 1 wherein the energy is in the form of light and wherein the converting means include photoelectric means for producing electrical signals from the beam of light and wherein the medium is in the form of a thin film and wherein the   
     
     
        means for producing a movement of the medium rotates the medium..]. .[.3. In combination for use with a medium having at successive positions on a track variable characteristics representing information recorded on the medium of visual images to obtain the reproduction of such information wherein the variable characteristics of the medium at the successive positions control the intensity of energy passing from the medium upon the direction of energy toward the medium and wherein the medium is in the form of a thin film and wherein the means for producing a movement of the medium rotates the medium, first means for producing a continuous rotation of the medium,   second means disposed relative to the medium for directing energy toward the medium at each instant to obtain variations in the energy passing from the medium at each instant in accordance with the variations in the characteristics of the medium at one of the successive positions along the track at that instant,   third means responsive to the energy passing at each instant from the track at the successive positions for producing signals in accordance with the variations in the energy passing from the track at that one of the successive positions along the track at that instant, the third means being variably positioned relative to the medium at each instant in a direction having a radial component for obtaining the response of the third means only to the light at the successive positions on the track, and   fourth means responsive at each instant to the signals produced by the third means for varying at that instant the position of the third means relative to the medium in the direction having the radial component for obtaining the response of the third means only to the light at the   
     
     
        successive positions on the track..]. .[.4.  In combination for use with a medium having at successive positions on a track variable characteristics representing information recorded on the medium of visual images to obtain the reproduction of such information wherein the variable characteristics of the medium control the intensity of energy passing from the medium upon the direction of energy toward the medium and where the information recorded on the medium at each successive position represents substantially less than a complete visual image, first means for producing a movement of the medium along the track of information recorded on the medium,   second means disposed relative to the medium for directing energy at the medium to obtain a modification of intensity of the energy passing from the medium in accordance with the variations in the characteristics of the medium at successive positions along the track of the medium,   third means responsive to the modified energy passing from the medium for dividing the modified energy into two component portions each having an intensity in accordance with the modification of the energy by the medium at successive positions along the track of the medium,   means responsive to the energy in at least one of the component portions for converting such energy to the information previously recorded on the medium, and   means responsive to the two component portions of the modified energy for positioning the third means relative to the medium in a direction transverse to the presentation of the successive positions on the track in accordance with any difference in intensity between the two component portions of the modified energy to obtain the energy beam passing from the   
     
     
        track in a particular disposition relative to the third means..]. .[.5. In combination for use with a medium having at successive positions on a track variable characteristics representing information recorded on the medium of visual images to obtain the reproduction of such information wherein the variable characteristics of the medium control the intensity of energy passing from the medium upon the direction of energy toward the medium and wherein the medium is in the form of a thin film and wherein the means for producing a movement of the medium rotates the medium, means operatively coupled to the medium for rotating the medium,   means disposed relative to the medium for directing energy at the medium,   means disposed relative to the medium for detecting the energy passing from the successive positions in the track on the medium,   reproducing means operatively coupled to the detecting means for dividing the detected energy into two component portions having relative intensities representative of the positioning of the detecting means relative to the track on the medium, the detecting means being variably positioned relative to the medium to obtain a tracking by the detecting means of the track on the medium,   means responsive to any difference in intensity between the two component portions of the detected energy for varying the position of the detecting means relative to the medium to minimize such differences in intensity between the two component portions, and   means responsive to the detected energy for converting such energy into the   
     
     
        information previously recorded on the medium..]. 6. In combination in a system for reproducing .Iadd.video .Iaddend.information from a rotatable medium where the medium has characteristics at progressive positions along a spiral path for modifying energy directed at the medium in representation of .Iadd.video .Iaddend.information previously recorded on the medium where the information recorded on the medium at each successive position along the spiral path represents substantially less than a complete visual image, means operatively coupled to the medium for producing a continuous rotation of the medium,   pickup means disposed relative to the medium including,   means for directing .[.energy.]. .Iadd.a beam of energy having a radius not greater than approximately one micron to enable the reproduction of the video information .Iaddend.at the medium at each instant to obtain a modification of the energy passing from the medium at that instant in accordance with the variations in the characteristics of the medium at the progressive positions along the spiral path, and   means responsive to the modified energy at each instant for producing signals having characteristics representative at that instant of the information recorded at the progressive positions along the spiral path on the medium, .[.and.].   means operatively coupled to the pickup means for varying in synchronism at each instant the position of the means for directing energy and the means responsive to the modified energy in a direction having a radial component to obtain a .Iadd.coarse .Iaddend.tracking at each instant of the characteristics at the progressive positions along the spiral path on the medium.Iadd., and means for varying in synchronism at each instant the position of the signal producing means relative to the energy directing means to obtain a fine tracking along the spiral path on the medium.   
     
     
        .Iaddend. .[.7.  In combination in a system for reproducing information from a rotatable medium where the medium has characteristics along a spiral path for modifying energy directed at the medium in representation of information previously recorded on the medium where the information recorded on the medium at each successive position along the spiral path represents substantially less than a complete visual image, first means operatively coupled to the medium for producing a rotation of the medium,   second means disposed relative to the medium for directing energy at the medium to obtain a modification of the energy passing from the medium in accordance with the variations in the characteristics along the spiral path on the medium,   third means responsive to the modified energy passing from the medium for producing a pair of signals each having a magnitude in accordance with the modification of the energy by the medium and in accordance with the disposition of the third means relative to the spiral path on the medium, the third means being movable relative to the medium in a direction having a radial component for obtaining a tracking by the third means of the information in the spiral path on the medium,   means responsive to any differences between the two component portions of the modified energy for positioning the third means relative to the medium in the direction having the radial component in accordance with any such difference to obtain a tracking by the third means of the spiral path on the medium, and   means responsive to at least one of the signals in the pair for reproducing the information previously recorded in the spiral path on the medium..].   
     
     
        .[.8.  In combination for use with a rotatable member and having information recorded on the member in a spiral track where the information recorded on the medium at each successive position along the spiral path represents substantially less than a complete visual image, a system for reproducing the information in the spiral track as the member rotates, including, first means operatively coupled to the annular member for producing a rotation of the member,   second means disposed in spaced relationship to the annular member for producing first and second signals having characteristics representative of the information in the spiral track on the member during the rotation of the member, the second means being movable relative to the medium in a direction having a radial component to obtain a tracking by the second means of the information in the spiral track on the annular member,   differential means responsive to the first and second signals for comparing the characteristics of the signals to produce a control signal in accordance with any difference between such characteristics,   driving means responsive to the control signal from the differential means for varying the position of the second means in the direction having the radial component to minimize the control signal and to obtain a tracking by the second means of the spiral track on the member, and   means responsive to at least one of the first and second signals for obtaining a reproduction of the information in the spiral track on the   
     
     
        member..]. 9. The combination set forth in claim .[.8.]. .Iadd.6 .Iaddend., including, means responsive to .[.at least one of the first and second signals.]. .Iadd.the modified energy at each instant .Iaddend.for varying the .[.position of the second.]. .Iadd.disposition of the signal producing means relative to the beam directing .Iaddend.means in the .[.annular.]. .Iadd.rotatable .Iaddend.direction along the spiral track to obtain a reproduction of information from the track at a rate corresponding to the recording of the information on the track. .[.10. In combination for use with an annular member rotatable in the annular direction and having information recorded on the member at progressive positions in a spiral track in the annular direction, a system for reproducing the information in the spiral track as the annular member rotates, including, means disposed relative to the annular member for directing energy at the member,   means disposed in displaced relationship to the annular member for receiving the energy passing from the member at the progressive positions in the spiral track on the member,   means operatively coupled to the receiving means for producing information in accordance with the characteristics of the energy received by the receiving means,   first means operatively coupled to the annular member for driving the member in the annular direction relative to the receiving means,   second means operatively coupled to the receiving means for driving the reproducing means in a second direction transverse to the annular direction and defining the spiral track with the annular direction,   third means responsive to the received energy and disposed relative to the receiving means for producing first and second signals each having characteristics representing the received energy at each instant,   means operatively coupled to the second means and responsive to any differences in the characteristics of the first and second signals for controlling the operation of the second means to obtain movements of the receiving means in a direction for reducing any such differences and for obtaining a tracking by the receiving means of the spiral track on the annular member, and   means operatively coupled to the third means and responsive to at least one of the first and second signals for varying the positioning of the third means in a third direction transverse to the second direction and the annular direction and along the spiral track in accordance with the characteristics of such signals to obtain the reproduction of the information in the spiral track at a rate related to the recording of the   
     
     
        information in the spiral track..]. .[.11.  The system set forth in claim 10, including, means responsive to at least one of the first and second signals and operatively coupled to the third means for varying the position of the third means in a direction for reducing any differences in 
     
     
        the characteristics of the first and second signals..]. 12. The combination set forth in claim .[.7.]. .Iadd.6 .Iaddend.wherein the .[.second means.]. .Iadd.means for directing a beam of energy .Iaddend.are disposed relative to the medium for directing light energy at the medium and wherein .[.the third means.]. .Iadd.said means responsive to said modified energy .Iaddend.are responsive to the modified light energy passing from the medium. .[.13. The combination set forth in claim 4 wherein the second means are disposed relative to the medium for directing light energy at the medium and wherein the third means are responsive to the light energy passing from the medium..]. .[.14. The combination set 
     
     
        forth in claim 3 wherein the medium is in the form of a thin disc..]. 15. In combination in a system for reproducing .Iadd.video .Iaddend.information from a rotatable medium where the medium has characteristics along a spiral path in the direction of rotation for modifying energy directed at the medium in representation of .Iadd.video .Iaddend.information previously recorded on the medium where the information recorded on the medium at each successive position along the spiral path represents substantially less than a complete visual image, means operatively coupled to the medium for continuously producing a rotation of the medium,   means disposed relative to the medium for directing .[.energy.]. .Iadd.a beam of energy having a radius not greater than approximately one micron .Iaddend.at the medium at each instant to obtain a modification of the energy passing from the medium at that instant in accordance with the variations in the characteristics of the medium along the spiral path.[.,.]. .Iadd.corresponding to the recorded video information, .Iaddend.   means responsive to the modified energy at each instant for producing signals having characteristics representative of the .Iadd.video .Iaddend.information recorded at the successive positions in the spiral path on the medium, and   means responsive to the signals produced by the last-mentioned means at each instant for varying the position of the energy-responsive means .Iadd.relative to the energy directing means .Iaddend.at that instant in a direction having a radial component to obtain a .Iadd.fine .Iaddend.tracking .[.by the energy-responsive means.]. of the characteristics at successive positions in the spiral path on the medium.   
     
     
         6. In combination for use with a medium having at successive positions variable characteristics representing .Iadd.video .Iaddend.information recorded on the medium of visual images to obtain the reproduction of such .Iadd.video .Iaddend.information wherein the variable characteristics of the medium control the amount of energy passing from the medium upon the passage of energy from the medium and wherein the information recorded on the medium at each successive position represents substantially less than a complete visual image, first means for providing a continuous movement of the medium to present the successive positions on the medium for the reproduction of the recorded information,   second means disposed on one side of the medium for continuously directing a beam of energy .Iadd.having a radius of not greater than approximately one micron .Iaddend.toward the medium at each instant to obtain variations in the intensity of the energy passing from the medium at that instant at one of the successive positions in accordance with the characteristics of the medium at that one of the successive positions.[.,.]. .Iadd.corresponding to the recorded video information, .Iaddend.   third means responsive to the energy passing from the medium at each instant at one of the successive positions on the medium for producing information in accordance with the characteristics of such energy,   fourth means for providing for variations in the position of at least one of the second and third means in a direction corresponding to the direction of the movement of the medium, and   fifth means operatively coupled to the third means and to the fourth means for obtaining at each instant variations in the positions of at least one of the second and third means by the fourth means in the direction corresponding to the direction of movement of the medium in accordance with the pattern of the information produced at each instant by the third means.[...]. .Iadd.to obtain a substantially constant rate of   
     
     
        reproduction. .Iaddend. 17. The combination set forth in claim 16 wherein the information is recorded in a spiral path on the medium and wherein the medium is rotated by the first means and wherein means are provided for obtaining movements of the medium relative to the second and third means in a direction having a radial component to obtain the reproduction of the 
     
     
        information in the spiral path on the medium. 18. In combination for use with a medium having at successive positions along a track variable characteristics representing information recorded on the medium of visual images to obtain the reproduction of such information wherein the variable characteristics of the medium at the successive positions along the track control the amount of energy passing from the medium upon the direction of energy toward the medium and wherein the information recorded on the medium at each successive position represents substantially less than a complete visual image, first means for providing a movement of the medium in a first direction corresponding to the successive positions along the track on the medium,   second means disposed relative to the medium for continuously directing a beam of energy at each instant toward the track on the medium to obtain a continuous passage of energy from the medium at that instant at one of the successive positions along the track in accordance with the characteristics of the medium at these successive positions,   third means disposed relative to the medium for receiving at each instant the energy passing from the medium at one of the successive positions along the track on the medium and for producing at that instant electrical signals having characteristics in accordance with the intensity of the energy at that one of the such successive positions,   fourth means operatively coupled to the second and third means for producing at that instant a variable force on at least one of the second and third means to vary the position at each instant of at least that one of the second and third means along the track in accordance with variations in this force,   fifth means operatively coupled to the third and fourth means and responsive at each instant to the pattern of the electrical signals produced by the third means for obtaining variations at that instant in the force provided by the fourth means on at least that one of the second and third means, and   sixth means operatively coupled to the third means for continuously producing information at each instant in accordance with the   
     
     
        characteristics of the electrical signals at that instant. 19. The combination set forth in claim 18 wherein the successive positions along the track define a spiral and wherein means are provided for producing a movement of the medium relative to the second and third means in a direction along the medium but transverse to the successive positions along the track to obtain the reproduction of the information at the 
     
     
        successive positions along the spiral track. .[.20.  In combination for use with a medium having at successive positions along a spiral track variable characteristics representing information recorded on the medium to obtain the reproduction of such information wherein the variable characteristics of the medium at the successive positions along the track control the amount of energy passing from the medium upon the direction of energy toward the medium, first means for providing a movement of the medium in a first direction corresponding to the successive positions along the track on the medium,   second means disposed relative to the medium for continuously directing a beam of energy toward the medium at each instant to obtain a passage of energy from the medium at that instant at one of the successive positions along the track in accordance with the characteristics of the medium at that one of the successive positions,   third means disposed relative to the medium for continuously receiving the energy passing from the medium at each instant at one of the successive positions along the track on the medium and for producing at that instant electrical signals having characteristics in accordance with the intensity of the energy at that one of such successive positions,   fourth means operatively coupled to the second and third means for obtaining a movement of the second and third means in a second direction transverse to the successive positions along the track but substantially parallel to the medium to provide a spiral scan of the medium by the second and third means,   fifth means operatively coupled to the fourth means and to the third means and responsive to the pattern of the electrical signals produced at each instant by the third means for obtaining variations in the rate of movement of the second and third means in the second direction at that instant in accordance with the pattern of such signals to obtain a tracking by the second and third means of the successive positions along the spiral track of the medium, and   sixth means operatively coupled to the third means for producing information in accordance with the characteristics of the electrical   
     
     
        signals..]. .[.21.  The combination set forth in claim 20 wherein the third means are variably positioned in a third direction transverse to the medium to provide adjustments in the position at which energy is received by the third means from the medium and wherein means are operatively coupled to the third means and are responsive to the electrical signals produced by the third means for varying the position of the third means in the third direction in accordance with the characteristics of the electrical signals to maintain the third means centered on the spiral 
     
     
        track..]. .[.22.  In combination for use with a medium having at successive positions along a spiral track variable characteristics representing information recorded on the medium to obtain the reproduction of such information wherein the variable characteristics of the medium at the successive positions along the track control the amount of energy passing from the medium upon the direction of energy toward the medium, first means for providing a movement of the medium in a first direction corresponding to the successive positions along the track on the medium,   second means disposed relative to the medium for directing a beam of energy toward the medium to obtain a passage of energy from the medium at the successive positions along the spiral track in accordance with the characteristics of the medium at these successive positions,   third means disposed relative to the medium for continuously receiving at each instant the energy passing from the medium at the successive positions along the spiral track on the medium and for continuously producing at that instant first and second electrical signals each having characteristics at that instant in accordance with the intensity of the energy passing from the medium at such successive positions along the spiral track and each having at that instant an intensity relative to that of the other signal dependent upon the position of the third means relative to the spiral track in a second direction transverse to the successive positions on the track but substantially parallel to the medium,   fourth means operatively coupled to the third means for producing at each instant information in accordance with the characteristics of at least one of the first and second electrical signals at that instant,   fifth means operatively coupled to the third means and responsive to the first and second electrical signals for producing a control signal at each instant in accordance with the difference in the intensity of the first and second electrical signals at that instant of time,   sixth means operatively coupled to the second and third means for producing a movement of the second and third means in the second direction, and   seventh means operatively coupled to the fifth and sixth means for varying the rate of movement of the second and third means by the fifth means at each instant in accordance with the characteristics of the control signal   
     
     
        produced by the sixth means at that instant..]. .[.23.  The combination set forth in claim 22, including, eighth means operatively coupled to the third means for obtaining a variable displacement of the third means in a third direction transverse to the medium and transverse to the successive positions along the spiral track on the medium for varying the relative characteristics of the first and second electrical signals, and   ninth means operatively coupled to the eighth means and to the third means for obtaining variations in the displacement of the third means by the eighth means in the third direction in accordance with the relative characteristics of the first and second electrical signals to provide substantially equal characteristics for the first and second electrical   
     
     
        signals..]. 24. The combination set forth in claim 19 wherein the second means are constructed to continuously direct the beam of energy toward the track on the medium in a controlled direction to obtain the continuous reproduction of information from the track on the medium at each instant. .Iadd.25. The combination set forth in claim 6, including, means operatively coupled to the pickup means for varying in synchronism at each instant the position of the directed energy relative to the means responsive to the modified energy in the direction of the spiral track to obtain the production of the signals at a controlled rate. .Iaddend.   
     
     
        .Iadd.6.  The combination set forth in claim 15, including, means responsive to the produced signals at each instant for varying the disposition of the energy responsive means relative to the beam directing means at that instant in the spiral direction to obtain the production of the information signals at a controlled rate. .Iaddend. .Iadd.27. The combination set forth in claim 19 wherein   the fifth means are responsive to the signals produced by the third means at each instant for obtaining variations in the transverse direction at that instant in the force provided by the fourth means on at least that one of the second and third means. .Iaddend. .Iadd.28. The combination set forth in claim 19 wherein   the fifth means are responsive to the signals produced by the third means at each instant for obtaining variations in the spiral direction at that instant in the force provided by the fourth means on at least that one of the second and third means. .Iaddend.