Associative memory employing holography

Claim 2

An associative memory system employing holographic techniques comprising: first and second coherent light beam arrays arranged to form an interference pattern, each array comprising a plurality of spaced parallel coherent light beams; first and second light wave modulators utilized to perform selective masking upon the beams of the first and second arrays, respectively, and each having means for selectively intercepting, in response to data to be stored, selected ones of the parallel coherent light beams of their associated array, said data being different from one to the other of said light wave modulators; means for causing each coherent beam of one of said arrays to diverge in a preselected direction; a photographic plate positioned to record the interference patterns formed between the modulated coherent light beam arrays; at least one of said arrays comprising a plurality of pairs of beams with each beam of said pairs being adapted to form an interference pattern with each beam of the remaining array wherein the light wave modulation at said selected masking means is such that each bit of said data is represented by the presence of only one beam of each pair of said parallel light beams, whereby each bit of information of a first of said data together with its complement is recorded on said photographic plate in the form of an interference pattern with the remaining type of said data.

Claim 3

An associative memory system comprising: a coherent light source for producing a pair of coherent light waves travelling in the Z-direction of a rectangular coordinate system made up of the mutually perpendicular directions X, Y and Z; a pair of light wave modulators each assigned to said light wave pairs; a first one of said light wave modulators having first means for discretely shifting the optical path of its associated light wave in the X-direction of said coordinate system, second means for dividing said X-shifted light waves into a plurality of pairs of parallel light beams arranged side by side in the Y-direction of said coordinate system thereby forming a first array; the remaining one of said light wave modulators having first means for discretely shifting the optical path of each of said light waves in the X-direction of said coordinate system and second means for dividing said X-shifted light waves into a plurality of light beams arranged side by side in the Y-direction of said coordinate system thereby forming a second array; said first modulator further comprising means for selectively intercepting at least one beam of each of said pairs of said first array in response to digital data of a first type so that each digit position of the data is represented by the presence of only one beam of the associated pair of parallel beams; the remaining one of said modulators further comprising means for selectively intercepting selected ones of the beams in said second array in response to digital data of a second type so that each digit position of said data is represented by the presence of an associated beam when in a first binary state and is represented by the absence of its associated beam when in the remaining binary state; means for causing one of the modulated outputs of said light wave modulators to diverge within a plane parallel to the YZ plane of said coordinate system; photographic recording means; means for directing the output of said diversions causing means and said light wave modulator unaccompanied by diversions causing means to said photographic means to form a defraction figure thereon, whereby said defraction figure recorded on said recording means consists of a pattern of the binary data of the first type combined with the true value of the binary data of the second type as well as combined with the complementary value of the binary data of the second type.

Claim 4

An associative memory system comprising: a coherent light source for producing a pair of coherent light waves travelling in the Z-direction of a rectangular coordinate system made up of the mutually perpendicular directions X, Y and Z; a pair of light wave modulators each assigned to said light wave pairs; a first one of said light wave modulators having first means for discretely shifting the optical path of its associated light wave in the X-direction of said coordinate system, second means for dividing said X-shifted light waves into a plurality of pairs of parallel light beams arranged side by side in the Y-direction of said coordinate system thereby forming a first array; the remaining one of said light wave modulators having first means for discretely shifting the optical path of each of said light waves in the X-direction of said coordinate system and second means for dividing said X-shifted light waves into a plurality of light beams arranged side by side in the Y-direction of said coordinate system thereby forming a second array; said first modulator further comprising means for selectively intercepting at least one beam of each of said pairs of said first array in response to digital data of a first type so that each digit position of the data is represented by the presence of only one beam of the associated pair of parallel beams; the remaining one of said modulators further comprising means for selectively intercepting selected ones of the beams in said second array in response to digital data of a second type so that each digit position of said data is represented by the presence of an associated beam when in a first binary state and is represented by the absence of its associated beam when in the remaining binary state; means for causing one of the modulated outputs of said light wave modulators to diverge within a plane parallel to the YZ plane of said coordinate system; photographic recording means; means for directing the output of said diversions causing means and said light wave modulator unaccompanied by diversions causing means to said photographic means to form a defraction figure thereon, whereby said defraction figure recorded on said recording means consists of a pattern of the binary data of the first type combined with the true value of the binary data of the second type as well as combined with the complementary value of the binary data of the second type.

Claim 7

The method of claim 3 further comprising the steps of: j. developing the exposed plate to fix the interference patterns formed thereon; k. illuminating the developed plate with a plurality of parallel light beams selectively intercepted in response to interrogation data in such a manner that said light beams represent the complementary value of each digit of interest of said interrogation data; and l. selectively reading out reproduced data from the defraction figure formed by said illumination wherein those positions in which an image is not formed represent the coincidence state.

Claim 8

Apparatus for forming a holographic pattern from two space modulated light beams comprising: first means for generating first and second coherent light beams arranged in parallel and moving in a first direction; second means responsive to a first group of digital deflection information for shifting said first beam by a predetermined amount in a direction transverse to said first direction; third means responsive to a second group of digital deflection information for shifting said second beam by a predetermined amount in a direction transverse to said first direction; fourth means for splitting said shifted first beam into a first array comprising a plurality of first substantially spaced parallel beams arranged along a line transverse to said first direction, each adjacent pair of beams representing the true and complementary state of an associated digit position; fifth means for splitting said shifted second beam into a second array comprised of a plurality of second substantially spaced parallel beams arranged along a line transverse to said first direction; sixth means for selectively masking one of said beams of each pair of said first array of beams in accordance with the binary state of each digit of a group of data to be stored; seventh means for selectively masking the beams of said second array of beams in accordance with the binary state of each digit of a second group of data to be stored; a photographic plate; eighth means for selectively combining the first and second arrays of beams at said plate to form a diffraction pattern.

Claim 9

Apparatus for forming a holographic pattern from two space modulated light beams comprising: first means for generating first and second coherent light beams arranged in parallel and moving in a first direction; second means responsive to a first group of digital deflection information for shifting said first beam by a predetermined amount in a direction transverse to said first direction; third means responsive to a second group of digital deflection information for shifting said second beam by a predetermined amount in a direction transverse to said first direction; fourth means for splitting said shifted first beam into a first array comprising a plurality of first substantially spaced parallel beams arranged along a line transverse to said first direction, each adjacent pair of beams representing the true and complementary state of an associated digit position; fifth means for splitting said shifted second beam into a second array comprised of a plurality of second substantially spaced parallel beams arranged along a line transverse to said first direction; sixth means for selectively masking one of said beams of each pair of said first array of beams in accordance with the binary state of each digit of a group of data to be stored; seventh means for selectively masking the beams of said second array of beams in accordance with the binary state of each digit of a second group of data to be stored; a photographic plate; eighth means for selectively combining the first and second arrays of beams at said plate to form a diffraction pattern.

Claim 10

The apparatus of claim 5 further comprising threshold means positioned between said eighth means and said plate for preventing passage from one of said first and second plurality of beams not combined with an associated beam of the other of said first and second plurality of beams.

Claim 11

An associative readout memory device employing holographic techniques comprising: a photographic plate having a diffraction pattern comprised of first and second space modulated coherent light waves; first means responsive to the complementary binary state of preselected interrogation digit positions of an interrogation word for selectively generating a plurality of coherent light waves equal in number to the number of interrogation digit positions; second means for selectively masking at least one of each pair of waves generated by said first means; said plate being positioned to intercept said light waves; third means including a plurality of pairs of devices sensitive to coherent light positioned to intercept coherent waves emitted by said plate; fourth means coupled to said third means for sensing the interception of no waves by said third means to recognize coincidence between the interrogation word and the pattern being scanned; fifth means responsive to said fourth means for causing said first and second means to illuminate that portion of the diffraction pattern being coincident with the preselected digits of said interrogation word to cause readout of all digit positions of that pattern portion; sixth means coupled to said third means for sensing the binary state of all digit positions of the pattern portion readout of said plate.

Claim 12

An associative readout memory device employing holographic techniques comprising: a photographic plate having a diffraction pattern comprised of first and second space modulated coherent light waves; first means responsive to the complementary binary state of preselected interrogation digit positions of an interrogation word for selectively generating a plurality of coherent light waves equal in number to the number of interrogation digit positions; second means for selectively masking at least one of each pair of waves generated by said first means; said plate being positioned to intercept said light waves; third means including a plurality of pairs of devices sensitive to coherent light positioned to intercept coherent waves emitted by said plate; fourth means coupled to said third means for sensing the interception of no waves by said third means to recognize coincidence between the interrogation word and the pattern being scanned; fifth means responsive to said fourth means for causing said first and second means to illuminate that portion of the diffraction pattern being coincident with the preselected digits of said interrogation word to cause readout of all digit positions of that pattern portion; sixth means coupled to said third means for sensing the binary state of all digit positions of the pattern portion readout of said plate.

Claim 13

An associative memory system employing holographic techniques comprising: first means for generating a first coherent light beam array comprised of a plurality of pairs of spaced parallel light beams; second means for modulating the beams of said first array in accordance with binary input data of a first type to be stored, each binary bit of said data being associated with a respective pair of said beams whererby each coherent light beam of each of said pairs of coherent light beams is the complement of the other in that only one or the other coherent light beam of each pair of beams is passed by said second means in accordance with the state of the associated binary bit; third means for generating a second array comprised of a plurality of spaced parallel coherent light beams; fourth means for modulating said second array in accordance with binary input data of a second type to be stored whereby each binary bit is associated with a respective beam and only those coherent light beams whose binary bits are in one binary state are passed by said modulating means while the remaining coherent light beams whose binary bits are in the opposite binary state are blocked by said fourth means; said third means being arranged to cause the beams of said second array to intersect with the beams of said first array to generate an interference pattern; a photographic plate sensitive to said interference pattern being positioned so as to record the aforesaid pattern on a preselected portion of said plate, wherein said pattern is comprised of said second array and forms an interference pattern with the first modulated array and with the complement of the first modulated array.

Claim 14

An associative memory system employing holographic techniques comprising: first means for generating a first coherent light beam array comprised of a plurality of pairs of spaced parallel light beams; second means for modulating the beams of said first array in accordance with binary input data of a first type to be stored, each binary bit of said data being associated with a respective pair of said beams whererby each coherent light beam of each of said pairs of coherent light beams is the complement of the other in that only one or the other coherent light beam of each pair of beams is passed by said second means in accordance with the state of the associated binary bit; third means for generating a second array comprised of a plurality of spaced parallel coherent light beams; fourth means for modulating said second array in accordance with binary input data of a second type to be stored whereby each binary bit is associated with a respective beam and only those coherent light beams whose binary bits are in one binary state are passed by said modulating means while the remaining coherent light beams whose binary bits are in the opposite binary state are blocked by said fourth means; said third means being arranged to cause the beams of said second array to intersect with the beams of said first array to generate an interference pattern; a photographic plate sensitive to said interference pattern being positioned so as to record the aforesaid pattern on a preselected portion of said plate, wherein said pattern is comprised of said second array and forms an interference pattern with the first modulated array and with the complement of the first modulated array.

Claim 15

The system of claim 8 further comprising: fifth means for shifting the orientation of the beams of said first array; sixth means for shifting the orientation of the beams of said second array in a direction transverse, whereby each pattern may be stored at different locations n said plate.

Claim 16

The system of claim 8 further comprising fifth means for diverging the beams of said first array so as to cause each beam to strike a large area of said plate.

Claim 17

The system of claim 8 wherein data stored in said plate is read out by fifth means for modulating said second array of beams in accordance with the complement of only those binary bits of said second type of data which are of interest, said modulated beams causing images to be generated at those positions which fail to compare with the bits of interest; a detector matrix of light detection means positioned behind said plate wherein each light detection means is associated with each stored point of said plate for detecting the absence of images at those points along said plate which compare with the binary bits of interest; sixth means coupled to said matrix for sequenTially deflecting the second array to those locations where no image has been formed to cause all of said beams of said second array and their complements to strike said plate and thereby generate the desired data pairs stored therein.