Methods of making holographic images

• US 4,415,225 A
• Filed: 11/10/1980
• Issued: 11/15/1983
• Est. Priority Date: 11/10/1980
• Status: Expired due to Term

• Current Assignee: Polaroid Corporation (PLR IP Holdings LLC)
• Original Assignee: Polaroid Corporation (PLR IP Holdings LLC)
• Inventors: Benton, Stephen A., Houde-Walter, William R., Mingace, Herbert S. Jr.
• Primary Examiner(s): ARNOLD, BRUCE
• Application Number:
  US06/205,758
• Time in Patent Office: 1,100 Days
• Field of Search: 350/3.83, 350/3.84, 350/3.85, 350/3.86
• US Class Current: 359/31
• CPC Class Codes: G03H 1/24 using white light , e.g. rainbow holograms
• CPC Class Codes: G03H 2001/2268 Rainbow hologram
• CPC Class Codes: Y10S 359/90 Methods

Abstract

A process of making holographic images comprising the steps of recording a hologram of a parallax limited aerial image formed by a lens on a recording surface with a reference beam at an angle of incidence to the recording surface that is preferably equal and opposite to the angle of incidence of the object beam to the recording surface, and illuminating the hologram with a beam of diverging or collimated light, preferably at the angle of incidence of the object beam to the recording surface and directed oppositely to the direction of the object beam during recording. Illumination can be with white light. The hologram may comprise superposed recordings of the aerial image made with light of different wavelengths to produce full color holographic images.

Claims

1. A process of making holographic images comprising the steps of recording a hologram of a parallax limited aerial image formed by a lens on a first side of a recording surface with a reference beam directed toward the surface from a source on said first side of said surface at an angle of incidence to the recording surface equal and opposite to the angle of incidence of the optical axis of the lens to the recording surface, and illuminating the hologram with a nonconverging beam of light directed toward the hologram from a source on a second side of said surface opposite said first side.

2. The process of claim 1, in which said illuminating beam is directed along said optical axis relative to the hologram.

3. The process of claim 2, in which said illuminating beam is collimated.

4. The process of claim 2, in which said illuminating beam is diverging.

5. A process of making holographic images comprising the steps of recording a hologram of an aerial image formed by a lens having an aperture limited to an elongated slit on a recording surface with a reference beam at an angle of incidence to the recording surface equal and opposite to the angle of incidence of a ray from the center of the slit to the center of the recording surface, and illuminating the hologram with a beam of diverging or collimated light directed toward the side of said surface opposite the side confronting the lens during recording.

6. The process of claim 5, in which the illuminating beam is at an angle of incidence equal to the angle of incidence of said ray.

7. A method of forming an orthoscopic holographic image of an object with a lens having an aperture limited to an elongated slit, a source of monochromatic light, a photographic plate, and a source of white light, comprising the steps of arranging the lens between the object and plate with a line from the center of the slit intersecting the center of the plate at a first angle of incidence to the plate and in position to form an aerial image of the object intersecting the plate, dividing a beam of light from the monochromatic source into a beam illuminating the object and a reference beam, focusing the reference beam to form a reference source at a distance from the plate less than the distance from the center of the slit to the plate and having a central ray incident on said plate on the same side as the lens at a second angle of incidence equal and opposite to said first angle of incidence, processing the plate to form a hologram, and illuminating said hologram with a diverging or parallel beam from said white light source from the side opposite that on which the hologram was recorded at an angle of incidence equal to said first angle of incidence to form a real image of said elongated aperture substantially equal in size to said elongated aperture through which an orthoscopic image of said object can be viewed in light of the wavelength of said monochromatic source in an image zone through which orthoscopic images of said object can be viewed in a wavelength that is a function of the position of the observer in the viewing zone.

8. A method of forming an orthoscopic holographic image of an object with a lens having an aperture limited to an elongated slit, a source of monochromatic light, a photographic plate, and a source of white light, comprising the steps of arranging the lens between the object and the plate with a line from the center of the slit intersecting the plate at a first angle of incidence to the plate and the lens in position to form an aerial image of the object intersecting the plate, dividing a beam of light from the monochromatic source into a beam illuminating the object and a reference beam, focusing the reference beam to form a reference source at a distance from the plate less than the distance from the center of the slit to the plate and incident on said plate on the same side as the lens, processing the plate to form a hologram, and illuminating said hologram with a beam from said white light source from the side opposite that on which the hologram was recorded to form a real image of said elongated aperture through which an orthoscopic image of said object can be viewed in light of the wavelength of said monochromatic source in an image zone through which orthoscopic images of said object can be viewed in a spectrum of wavelength which is a function of the position of the observer in the viewing zone.

9. A method of forming an orthoscopic holographic image of an object with a lens having an elongated parallax limiting aperture, a source of monochromatic light, a photographic plate, and a source of white light, comprising the steps of arranging the lens between the object and the plate with its optical axis intersecting the plate at a first angle of incidence to the plate and in position to form an aerial image of the object intersecting the plate, dividing a beam of light from the monochromatic source into a beam illuminating the object and a reference beam, focusing the reference beam to form a reference source at a distance from the plate less than the distance from the elongated aperture to the plate and having a central ray incident on said plate on the same side as the lens at a second angle of incidence equal and opposite to said first angle of incidence, processing the plate to form a hologram, and illuminating said hologram with a diverging or parallel beam from said white light source from the side opposite that on which the hologram was recorded at an angle of incidence equal to said first angle of incidence to form a real image of said elongated aperture substantially equal in size to said elongated aperture through which an orthoscopic image of said object can be viewed in light of the wavelength of said monochromatic source in an image zone through which orthoscopic images of said object can be viewed in a wavelength that is a function of the position of the observer in the viewing zone.

10. A process of making holographic images, comprising the steps of holographically recording a parallax limited aerial image of an object illuminated with a source of monochromatic light formed by a lens on a recording surface with a reference beam from said source at an angle of incidence to said surface equal and opposite to the angle of incidence of the optical axis of the lens to said surface, and illuminating said recorded image from the side opposite that on which it was recorded with a beam directed along the direction of said optical axis relative to said surface during recording.

11. A method of forming an orthoscopic holographic image of an object, comprising the steps of holographically recording on a photographic plate a parallax limited image of the object formed by a lens having an optical axis at a first angle of incidence to said photographic plate, said plate being intersected by said image, using a reference beam propagated along a reference axis at a second angle of incidence equal and opposite to said first angle of incidence, processing said plate to form a hologram, and illuminating said hologram with a reference beam directed along said optical axis relative to said plate.

12. A method of forming an orthoscopic holographic image of an object with a lens having an elongated parallax limiting aperture, a source of monochromatic light, a photographic plate, a mirror, and a source of white light, comprising the steps of arranging the mirror between the object and the lens and the lens between the mirror and the plate with the optical axis of the lens intersecting the plate at a first angle of incidence to the plate and in position to form an aerial image of the object intersecting the plate from the virtual image of the object in the mirror, dividing a beam of light from the monochromatic source into a beam illuminating the object and a reference beam, focusing the reference beam to form a reference source at a distance from the plate less than the distance from the elongated aperture to the plate and having a central ray incident on said plate on the same side as the lens at a second angle of incidence equal and opposite to said first angle of incidence, processing the plate to form a hologram, and illuminating said hologram with a diverging or parallel beam from said white light source from the side opposite that on which the hologram was recorded at an angle of incidence equal to said first angle of incidence to form a real image of said elongated aperture substantially equal in size to said elongated aperture through which an orthoscopic image of said object can be viewed in light of the wavelength of said monochromatic source in an image zone through which orthoscopic images of said object can be viewed in a wavelength that is a function of the position of the observer in the viewing zone.

13. A process of making holographic images, comprising the steps of holographically recording a parallax limited aerial image of the virtual image in a mirror of an object illuminated with a source of monochromatic light formed by a lens on a recording surface with a reference beam from said source at an angle of incidence to said surface equal and opposite to the angle of incidence of the optical axis of the lens to said surface, and illuminating said recorded image from the side opposite that on which it was recorded with a beam directed along the direction of said optical axis relative to said surface during recording.

14. A method of forming an orthoscopic holographic image of an object, comprising the steps of holographically recording on a photographic plate a parallax limited aerial image of the object formed by a lens from a mirror image of the object, said lens having an optical axis at a first angle of incidence to said photographic plate, said plate being intersected by said aerial image, using a reference beam propagated along a reference axis at a second angle of incidence equal and opposite to said first angle of incidence, processing said plate to form a hologram, and illuminating said hologram with a reference beam directed along said optical axis relative to said plate and propagated toward the plate from the side opposite the side confronting the lens during recording.

15. The process of making holographic images of an object with a lens having an aperture limited to an elongated slit, comprising the steps of placing the lens in position to form an aerial image of the object, placing a photographic plate in a position in which it would intersect an aerial image of the object formed by the lens with a point O in the center of the plate at a distance S from the center of the slit and with a ray from the center of the slit at an angle θ

₁ to the normal to the plate at point O, making a holographic exposure by illuminating the object with a source of monochromatic light of wavelength λ

₁ while illuminating the plate with a reference beam from said source formed as a point source at a distance R from the point O on the same side of the plate as the lens and in the plane of said normal and said ray and on the other side of said normal from said ray and at an angle θ

₂ to said normal, where θ

₂ =-θ

₁ and O<

(R/S)<

1, processing said plate to make a hologram, and illuminating said hologram with a source of white light at a distance I from the plate and on the opposite side of the plate from the side on which said lens and reference point source were located during said holographic exposure at an angle of incidence θ

₃ to said normal to form a real image of said slit through which an undistorted orthoscopic image of said object can be seen in a light of wavelength λ

₂, which slit image is located at a distance S from said slit and at an angle θ

₅ to said normal, where ##EQU28## and sin θ

₅ =(2λ

₂ /λ

₁) sin θ

₂ +sin θ

₃, the angles θ

_i being considered positive or negative according as a rotation in one sense or an opposite sense would carry the ray into said normal, respectively.

16. The process of claim 15 in which I=∞

, λ

₁ =λ

₂ and O<

(R/S)≦

1/2.

17. The process of claim 15, in which θ

₁ =θ

₃.

18. The process of claim 17, in which I=∞

, λ

₁ =λ

₂ and O<

(R/S)=1/2.

19. A method of forming a polychromatic orthoscopic holographic image of an object with a lens having an aperture limited to an elongated slit, a plurality of sources of monochromatic light at different wavelengths, a photographic plate, and a source of white light, comprising the steps of arranging the lens between the object and the plate with a line from the center of the slit intersecting the center of the plate at a first angle of incidence to the plate and in position to form an aerial image of the object intersecting the plate, dividing beams of light from the monochromatic sources into beams illuminating the object and reference beams, focusing the reference beams to form reference sources each at a common distance from the plate less than the distance from the center of the slit to the plate and each having a central ray incident on said plate on the same side as the lens at a second angle of incidence equal and opposite to said first angle of incidence, processing the plate to form a hologram, and illuminating said hologram with a diverging or parallel beam from said white light source from the side opposite that on which the hologram was recorded at an angle of incidence equal to said first angle of incidence to form a real image of said elongated aperture substantially equal in size to said elongated aperture through which a polychromatic othoscopic image of said object can be viewed.

20. A method of forming a polychromatic orthoscopic holographic image of an object with a lens having an aperture limited to an elongated slit, a plurality of sources of monochromatic light at different wavelengths, a photographic plate, and a source of white light, comprising the steps of arranging the lens between the object and the plate with a line from the center of the slit intersecting the plate at a first angle of incidence to the plate and the lens in position to form an aerial image of the object intersecting the plate, dividing beams of light from the monochromatic sources into beams illuminating the object and reference beams, focusing the reference beams to form reference sources at a common distance from the plate less than the distance from the center of the slit to the plate and incident on said plate on the same side as the lens at a common angle of incidence, processing the plate to form a hologram, and illuminating said hologram with a beam from said white light source from the side opposite that on which the hologram was recorded to form a real image of said elongated aperture through which an image of said object can be viewed in light of a plurality of wavelengths in an image zone through which images of said object can be viewed in colors which are a function of the position of the observer in the viewing zone.