Method of producing a big size holographic projection screen for displaying a three-dimensional color images without color deterioration

An apparatus for displaying stereoscopic or multiview color image on a holographic screen locating on xy-plane of three dimensional space, comprising:

• a projector for producing an image projection beam;
• and
• a holographic screen on x-y plane of a three-dimensional space, center of said holographic screen being disposed on y-axis, for diffracting the image projection beam to be collected on a focusing point,
• whereby the stereoscopic or multiview color image can be displayed on the focusing point at a distance Z4 from said holographic screen by said projector disposed at a distance Z3 from said holographic screen, if a view's eyes are placed at viewing zones being composed of superposed diffuser's real images of the different colors,
• wherein said holographic screen is made by using a narrow and elongate slit-shaped diffuser having a length of Z22−Z21 disposed perpendicularly to the holographic screen,
• wherein Z21, distance to the nearest point of the diffuser from xy-plane, Z22, distance to the farthest point from xy-plane, are calculated from following equations:
• Z
• 21
• =
• 1
• [
• 1
• Z
• 1
• 2
• +
• ρ
• max
• 2
• +
• λ
• 1
• λ
• 21
• ⁢
• (
• 1
• Z
• 3
• 2
• +
• ρ
• max
• 2
• +
• 1
• Z
• 4
• 2
• +
• ρ
• max
• 2
• )
• ]
• 2
• -
• ρ
• max
• 2
• (
• 7
• )
• Z
• 22
• =
• 1
• 1
• Z
• 1
• +
• λ
• 1
• λ
• 22
• ⁢
• (
• 1
• Z
• 3
• +
• 1
• Z
• 4
• )
• (
• 8
• )
• where λ1 is the wavelength of the laser used for the holographic screen recording, λ21 is the shortest wavelength of the displayed image, λ22 is the longest wavelength of the displayed image, Z1 is distance to the reference beam source from the XY-plane in the recording setup, Z3 is distance from the projector to the holographic screen in the image projection setup, Z4 is distance from the holographic screen to the focusing point of the diffracted beams, and ρmax is distance from Z-axis of the farthermost point of the holographic screen.

A method of producing a holographic screen for displaying a stereoscopic or multiview color image, comprising:

• placing a photoplate on the x-y plane of a three-dimensional space, center of the photoplate being disposed on the y-axis on the distance of H/2+h from the origin of a three-dimensional space, wherein H is the photoplate height (size in the y-direction) and h is distance of the photoplate boundary from the origin;
• splitting the laser beam into a reference beam and object beam, both beams being used to illuminate the photoplate surface;
• shaping the reference beam as spherical wave diverging from the point on the z-axis which is located a distance Z1 from the origin of a three-dimensional space;
• shaping the object beam so to illuminate the photoplate through a elongated narrow strip-shaped diffuser disposed precisely along the z-axis;
• and
• recording the interference pattern, which is arising as a result of superposition of the reference wave with an object wave from diffuser on the photoplate,
• wherein to provide displaying of the color image in the bandwidth from λ21 (shortest wavelength) up to λ22 (the longest wavelength), the coordinates Z21 and Z22 of the diffuser end points are calculated from the following equations:
• Z
• 21
• =
• 1
• [
• 1
• Z
• 1
• 2
• +
• ρ
• max
• 2
• +
• λ
• 1
• λ
• 21
• ⁢
• (
• 1
• Z
• 3
• 2
• +
• ρ
• max
• 2
• +
• 1
• Z
• 4
• 2
• +
• ρ
• max
• 2
• )
• ]
• 2
• -
• ρ
• max
• 2
• (
• 7
• )
• Z
• 22
• =
• 1
• 1
• Z
• 1
• +
• λ
• 1
• λ
• 22
• ⁢
• (
• 1
• Z
• 3
• +
• 1
• Z
• 4
• )
• (
• 8
• )
• where λ1 is the wavelength of the laser used for the screen recording, Z3 is distance from the projector to the screen in the image projection setup, Z4 is distance from the holographic screen to a focusing point of the diffracted beams, and ρmax is distance from Z-axis of the farthermost point of the photoplate.

A method for producing a holographic screen by using a diffuser disposed along z-axis of three dimensional space and perpendicular to a photoplate on the xy plane of a three dimensional space, comprising:

• determining a wavelength λ1 of laser beam used for a holographic screen recording setup and a distance Z1 to a reference beam source from xy plane;
• determining a shortest wavelength λ21 and a longest wavelength λ22 of an image to be displayed, a distance Z3 from a projector to the holographic screen, and a distance Z4 from the holographic screen to a focusing point of diffracted beams in an image projection setup;
• calculating a distance ρmax from Z-axis of the farthermost point of the photoplate with size of B×H, wherein center of the photoplate is disposed on the y-axis on the distance of H/2+h from the origin of the three-dimensional space, where H is the photoplate height (size in the y-direction) and h is distance of the photoplate boundary from the origin;
• calculating a distance Z21 to the nearest point of the diffuser from xy-plane and a distance Z22 to the farthest point from xy plane by using following equations:
• Z
• 21
• =
• 1
• [
• 1
• Z
• 1
• 2
• +
• ρ
• max
• 2
• +
• λ
• 1
• λ
• 21
• ⁢
• (
• 1
• Z
• 3
• 2
• +
• ρ
• max
• 2
• +
• 1
• Z
• 4
• 2
• +
• ρ
• max
• 2
• )
• ]
• 2
• -
• ρ
• max
• 2
• (
• 7
• )
• Z
• 22
• =
• 1
• 1
• Z
• 1
• +
• λ
• 1
• λ
• 22
• ⁢
• (
• 1
• Z
• 3
• +
• 1
• Z
• 4
• )
• (
• 8
• )
• recording interference patterns on the photoplate by using the diffuser disposed along z-axis from Z21 to Z22 to produce a holographic screen.