US 4,778,262 A · Computer aided holography and holographic computer graphics

Abstract

Methods for generating holograms from a computer model of any object using a combination of numerical and optical means and the holograms produced thereby. An illumination model is provided to specify sources of light rays and dispersion particles of the object. Each light ray being specified by a path and an intensity function is traceable from a source via the object to a set of points in space by the computer. The hologram is synthesized from a plurality of smaller hologram elements. Each individual element sustains a field of view of the object. The light rays from the object lying within the field of view and along the lines of sight are sampled by the computer. Optical means are employed to physically reproduce the sampled light rays using coherent radiation. The reproduced coherent light rays are then interfered with a coherent reference beam to form the hologram element. Alternatively, the hologram elements are calculated by the computer with an analogous technique.

Claims17

Dependent claims

A method of constructing a hologram, comprising the steps of:

providing a computer database of information of at least a portion of an object scene and its illumination,
defining as computer data a hologram surface with respect to said object scene,
dividing the hologram surface into a plurality of elemental areas by means of computer specified boundaries,
determining for at least some of said plurality of hologram surface areas, by means of a computer, the intensity and direction of a selected sample of a plurality of rays emanating from an illuminated object that lie only along straight line paths that pass through the given surface area, and
constructing a plurality of holograms on a common holographic detector, each of said holograms being formed by redirecting onto the holographic detector the determined intensity and direction of the sample of rays associated with a corresponding one of the plurality of hologram surface contiguous elemental areas,
whereby a completed hologram is formed that is capable of reconstructing an image of said object scene.

3 more elements

A method of constructing a hologram, comprising the steps of:

forming a computer representation of a geometric shape of an object, and its light dispersion characteristics,
defining a holographic surface relative to the object, said holographic surface being made up of a plurality of individually defined surface elements,
specifying at least one source of object illumination rays,
tracing a plurality of rays from said source to the object and thence to a set of points in space, each such ray being specifiable by a path and a position dependent intensity function,
for each of at least some of said hologram surface elements, selecting a representative sample of said rays from the object with paths lying along a line extending through the surface element,
physically reproducing in light said selected sample of rays associated with each said hologram surface element using a first coherent radiation beam such that said paths and intensity functions are preserved,
directing said reproduced light rays and a second radiation beam coherent with said first radiation as a reference beam to said associated surface element to form an interference pattern thereof, and
recording and assembling said interference pattern associated with each said surface element at said holographic surface to synthesize said hologram thereof.

5 more elements

Dependencies are inferred from the claim text.

Computer aided holography and holographic computer graphics

Life of this patent

Computer aided holography and holographic computer graphics

Life of this patent

Abstract

Claims17