Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

REAL TIME IMAGE PROCESSING BY BACKWARD STIMULATED PHOTON ECHOES

M. K. Kim, Ravinder Kachru

Published Jul 18, 1988• 0 citations
OpenAlex

Abstract

We report the first demonstration of the ability of backward stimulated photon echo to process spatial images in real time. The image processing is accomplished by the correlation and convolution properties of the backward stimulated photon echoes. And by extension, this makes possible to perform pattern recognition, mixed binary multiplication, and other mathematical operations on spatial images.

Related papers

Spatial mixed binary multiplication by photon echoes

D. Manganaris, P. Talagala, M. K. Kim

We demonstrate mixed binary multiplication of two or three numbers represented as spatial bit patterns by using a backward stimulated photon echo in a low-temperature solid activated by rare-earth ions. The photon-echo output image is the convolution-correlation of input images in a holographic arrangement, which can be interpreted as multiplication in a mixed binary format. The computation is extremely fast (~ 50 ns) and may be combined with temporal data processing for a versatile vector and matrix processor.

Applied Optics•May 10, 1992•3 citations

Pattern recognition by photon echoes

P. Talagala, M. K. Kim

We demonstrate, we believe for the first time, the capability of spatial pattern recognition by backward stimulated photon echo (BSPE) in a low temperature solid activated by rare earth ions. The BSPE experiment is done with three time-delayed input laser pulses. The first pulse (DATA) contains several characters in its beam profile, the second pulse (WRITE) is a plane wave, and the third (READ) has the search character. The echo pulse profile has peak intensity at the position of the search character. The experiment has a time scale of several tens of nanoseconds. Pattern recognition by BSPE is a result of the convolution/correlation property of holographic four-wave mixing geometry. In contrast to the photorefractive processes, however, the BSPE in rare earth-doped solids is a resonant coherent optical transient effect. By combining spatial and temporal holographic processes of BSPE, it would be possible to construct a high density, high speed optical processor of spatial and temporal data using BSPE.

Annual Meeting Optical Society of America•Jan 1, 1991•0 citations

Nanosecond image processing using stimulated photon echoes

E. Y. Xu, M. K. Kim, Stefan Kröll +2 more

Processing of two-dimensional images on a nanosecond time scale is demonstrated using the stimulated photon echoes in a rare-earth-doped crystal (0.1 at. % Pr(3+):LaF(3)). Two spatially encoded laser pulses (pictures) resonant with the (3)P(0)-(3)H(4) transition of Pr(3+) were stored by focusing the image pulses sequentially into the Pr(3+):LaF(3) crystal. The stored information is retrieved and processed by a third read pulse, generating the echo that is the spatial convolution or correlation of the input images. Application of this scheme to high-speed pattern recognition is discussed.

Optics Letters•Mar 26, 1990•35 citations

Spatial binary multiplication by photon echoes

D. Manganaris, M. K. Kim

The phase conjugation property of backward-stimulated photon echo (BSE) has numerous potential applications in optical data storage and processing. We demonstrate mixed binary multiplication of spatially encoded bit patterns, by taking advantage of the fact that the geometry of BSE is analogous to that of conventional holography or four-wave mixing of nonlinear optics, where an object (data) and a reference (write) beams interfere to create a grating inside the medium, and another reference (read) beam is diffracted from that grating. When all three input beams contain structures, the output pattern is the convolution and correlation of the input patterns, which, with certain arrangements and interpretation, can be used for multiplication of binary numbers. The experiments were done by using a 477.8 nm transition of praseodymium ion-doped in single-crystal lanthanum trifluoride.

Annual Meeting Optical Society of America•Jan 1, 1990•0 citations

High-speed pattern recognition by using stimulated echoes

Xiao A. Shen, Ravinder Kachru

We present experimental results demonstrating the use of stimulated echoes for high-speed pattern recognition. One data image and two reference images (spatially encoded laser pulses) were stored and processed in a Pr(3+):LaF(3) crystal by focusing the pulses sequentially into the storage material. The processed information was later retrieved by a read pulse, generating two temporally separated echo images that are the spatial correlations between the data and reference images. Identification of the data image was accomplished by finding the echo image that showed the highest spatial correlation with the data image. The present processing speed is 30 ns per correlation operation.

Optics Letters•Apr 1, 1992•22 citations

Methods of optical information processing based on the accumulated-stimulated and modified-stimulated photon echo

Eduard A. Manykin, Sergey M. Zakharov

Dynamic spatial and temporal properties of accumulated stimulated and modified stimulated photon echoes are considered. Possible applications to optical information processing systems for the temporal compression of the recorded information, the erasure of information, as well as for the correlation analysis of optical images are discussed.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jul 12, 1993•0 citations
We report the first demonstration of the ability of backward stimulated photon echo to process spatial images in real time. The image processing is accomplished by the correlation and convolution properties of the backward stimulated photon echoes. And by extension, this makes possible to perform pattern recognition, mixed binary multiplication, and other mathematical operations on spatial images.
We demonstrate mixed binary multiplication of two or three numbers represented as spatial bit patterns by using a backward stimulated photon echo in a low-temperature solid activated by rare-earth ions. The photon-echo output image is the convolution-correlation of input images in a holographic arrangement, which can be interpreted as multiplication in a mixed binary format. The computation is extremely fast (~ 50 ns) and may be combined with temporal data processing for a versatile vector and matrix processor.
We demonstrate, we believe for the first time, the capability of spatial pattern recognition by backward stimulated photon echo (BSPE) in a low temperature solid activated by rare earth ions. The BSPE experiment is done with three time-delayed input laser pulses. The first pulse (DATA) contains several characters in its beam profile, the second pulse (WRITE) is a plane wave, and the third (READ) has the search character. The echo pulse profile has peak intensity at the position of the search character. The experiment has a time scale of several tens of nanoseconds. Pattern recognition by BSPE is a result of the convolution/correlation property of holographic four-wave mixing geometry. In contrast to the photorefractive processes, however, the BSPE in rare earth-doped solids is a resonant coherent optical transient effect. By combining spatial and temporal holographic processes of BSPE, it would be possible to construct a high density, high speed optical processor of spatial and temporal data using BSPE.
Processing of two-dimensional images on a nanosecond time scale is demonstrated using the stimulated photon echoes in a rare-earth-doped crystal (0.1 at. % Pr(3+):LaF(3)). Two spatially encoded laser pulses (pictures) resonant with the (3)P(0)-(3)H(4) transition of Pr(3+) were stored by focusing the image pulses sequentially into the Pr(3+):LaF(3) crystal. The stored information is retrieved and processed by a third read pulse, generating the echo that is the spatial convolution or correlation of the input images. Application of this scheme to high-speed pattern recognition is discussed.
The phase conjugation property of backward-stimulated photon echo (BSE) has numerous potential applications in optical data storage and processing. We demonstrate mixed binary multiplication of spatially encoded bit patterns, by taking advantage of the fact that the geometry of BSE is analogous to that of conventional holography or four-wave mixing of nonlinear optics, where an object (data) and a reference (write) beams interfere to create a grating inside the medium, and another reference (read) beam is diffracted from that grating. When all three input beams contain structures, the output pattern is the convolution and correlation of the input patterns, which, with certain arrangements and interpretation, can be used for multiplication of binary numbers. The experiments were done by using a 477.8 nm transition of praseodymium ion-doped in single-crystal lanthanum trifluoride.
We present experimental results demonstrating the use of stimulated echoes for high-speed pattern recognition. One data image and two reference images (spatially encoded laser pulses) were stored and processed in a Pr(3+):LaF(3) crystal by focusing the pulses sequentially into the storage material. The processed information was later retrieved by a read pulse, generating two temporally separated echo images that are the spatial correlations between the data and reference images. Identification of the data image was accomplished by finding the echo image that showed the highest spatial correlation with the data image. The present processing speed is 30 ns per correlation operation.