Holographic recording system for large objects

Claim 1

A holographic recording system for recording a hologram of diffusely reflecting objects located in a given object space having a first given length employing coherent light waves having a coherence length significantly smaller than said first given length, said system comprising: a. means including at least an approximately single-frequency mode laser having an optical resonant cavity of a second given length for producing first and second mutually coherent components of coherent light waves each having said coherence length, b. a hologram recording medium having a first selected location chosen with respect to said given object space, c. object illuminating means comprising a single objectilluminating plane mirror and a single concave mirror having respective second and third locations chosen with respect to both said given object space and said medium so that illumination of said concave mirror with said first component of said coherent light waves reflects a single divergent beam of coherent light waves incident on said plane mirror having rays at those angles that result in the illumination of each point of said given object space with an illuminating ray of a single divergent beam of light waves reflected from said plane mirror, thereby to cause the illumination of said hologram recording medium with an object beam comprising reflected rays of said coherent light waves diffusely reflected from each illuminated point of any object within said given object space, said first and third selected locations being such that the sum of the lengths of any pair of illuminating and reflected rays of any one illuminated point of an object differs from a predetermined length by no more than said coherence length, and d. means for illuminating said concave mirror with said incident beam of first component of said coherent light waves to derive the light which illuminates said hologram recording medium as said object beam and simultaneouslY directly illuminating said hologram recording medium with a reference beam of said second component of said coherent light waves which is angularly displaced from said object beam, the difference in the overall length of the path of light derived from said first-component of said coherent light waves which illuminates said hologram recording medium as said object beam and the overall length of the path of light which illuminates said hologram recording medium directly as said reference beam being substantially equal to an even integral multiple of said second given length.

Claim 4

A system for recording on a hologram medium an object having a first given length and located in a given object space employing coherent light waves having a coherence length significantly smaller than said first given length, said hologram medium having a first selected location chosen with respect to said given object space, said system comprising: a. means for producing from an approximately single-frequency mode laser having an optical resonant cavity of a second given length first and second mutually coherent components of coherent light waves each having said coherence length, b. object illuminating means comprising a single object-illuminating plane mirror and a single concave mirror having respective second and third locations chosen with respect to both said given object space and said medium so that illumination of said concave mirror with said first component of said coherent light waves reflects a single divergent beam of coherent light waves incident on said plane mirror having rays at those angles that result in the illumination of each point of said given object space with an illuminating ray of a single divergent beam of light waves reflected from said plane mirror, thereby to cause the illumination of said medium with an object beam comprising reflected rays of said coherent light waves diffusely reflected from each illuminated point of any object within said given object space, said first and third selected locations being such that the sum of the lengths of any pair of illuminating and reflected rays of any one illuminated point of an object differs from a predetermined length by no more than said coherence length, and c. means for illuminating said concave mirror with said incident beam of said first component of said coherent light waves to derive the light which illuminates said medium as said object beam and simultaneously directly illuminating said medium with a reference beam of said second component of said coherent light waves which is angularly displaced from said object beam, the difference in the overall length of the path of light derived from said first-component of said coherent light waves which illuminates said hologram recording medium as said object beam and the overall length of the path of light which illuminates said hologram recording medium directly as said reference beam being substantially equal to an even integral multiple of said second given length.

Claim 5

A system for recording on a hologram medium an object having a first given length and located in a given object space employing coherent light waves having a coherence length significantly smaller than said first given length, said hologram medium having a first selected location chosen with respect to said given object space, said system comprising: a. means for producing from an approximately single-frequency mode laser having an optical resonant cavity of a second given length first and second mutually coherent components of coherent light waves each having said coherence length, b. object illuminating means comprising a single object-illuminating plane mirror and a single concave mirror having respective second and third locations chosen with respect to both said given object space and said medium so that illumination of said concave mirror with said first component of said coherent light waves reflects a single divergent beam of coherent light waves incident on said plane mirror having rays at those angles that result in the illumination of each point of said given object space with an illuminating ray of a single divergent beam of light waves reflected from said plane mirror, thereby to cause the illumination of said medium with an object beam comprising reflected rays of said coherent light waves diffusely reflected from each illuminated point of any object within said given object space, said first and third selected locations being such that the sum of the lengths of any pair of illuminating and reflected rays of any one illuminated point of an object differs from a predetermined length by no more than said coherence length, and c. means for illuminating said concave mirror with said incident beam of said first component of said coherent light waves to derive the light which illuminates said medium as said object beam and simultaneously directly illuminating said medium with a reference beam of said second component of said coherent light waves which is angularly displaced from said object beam, the difference in the overall length of the path of light derived from said first-component of said coherent light waves which illuminates said hologram recording medium as said object beam and the overall length of the path of light which illuminates said hologram recording medium directly as said reference beam being substantially equal to an even integral multiple of said second given length.