Artículos de revistas
Phase-conjugate interferometer to estimate refractive index and thickness of transparent plane parallel plates
Institución
Resumen
SE PROPONE UNA TÉCNICA PARA MEDIR ÍNDICES DE REFRACCIÓN Y ESPESORES DE PLACAS DIELÉCTRICAS PLANO PARALELAS HOMOGÉNEAS EMPLEANDO UN INTERFEROMETRO CON FASE CONJUGADA, EN EL CUAL SE USA EL CONTEO DE FRANJAS. EL HAZ LUMINOSO INCIDE EN UNA PLACA INCLINADA BAJO INSPECCIÓN ANTES DE ENTRAR EN UN INTERFEROMETRO EQUIPADO CON UN ESPEJO CONJUGADOR DE FASE, Y SE REALIZA UN CONTEO DE LAS FRANJAS QUE PASAN POR DETERMINADA REFERENCIA EN EL PLANO DE OBSERVACIÓN, PROPORCIONANDO LOS CAMBIOS DE FASE EN FUNCIÓN DEL ÁNGULO DE INCLINACIÓN. LOS DATOS OBTENIDOS SE AJUSTAN A UN MODELO, EL CUAL CONDUCE A LA DETERMINACIÓN, TANTO DEL ÍNDICE DE REFRACCIÓN COMO DEL ESPESOR, SIMULTÁNEAMENTE. EN ESTE TRABAJO SE DISCUTEN LOS DATOS EXPERIMENTALES PROVENIENTES DE DOS INTERFEROMETROS PARA SU COMPARACIÓN. UNO DE ELLOS TIENE UN ESPEJO CONJUGADOR BASADO EN UN CRISTAL BSO FOTORREFRACTIVO, MIENTRAS QUE EL OTRO ES UNA VARIANTE CON ESPEJOS CONVENCIONALES. SE MUESTRA QUE LA SENSIBILIDAD DE LA FASE DEL INTERFEROMETRO CON CONJUGADOR DE FASE NO RESULTA SER SIMPLEMENTE EL DOBLE DE LA SENSIBILIDAD DE LA VERSIÓN CONVENCIONAL.AbstractA TECHNIQUE TO ESTIMATE THE REFRACTIVE INDEX AND THICKNESS OF HOMOGENEOUS PLANE PARALLEL DIELECTRIC PLATES IS PROPOSED USING A PHASE-CONJUGATE INTERFEROMETER, IN WHICH COUNTING OF INTERFERENCE FRINGES IS EMPLOYED. THE LIGHT BEAM IMPINGES A TILTED PLATE BEFORE IT ENTERS A PHASE-CONJUGATE INTEFEROMETER, AND COUNT OF THE FRINGES PASSING THROUGH A GIVEN REFERENCE AT THE OBSERVING PLANES GIVES THE PHASE CHANGES AS A FUNCTION OF TILTING ANGLE. THE OBTAINED DATA IS FITTED TO A MATHEMATICAL MODEL, WHICH LEADS TO THE DETERMINATION OF BOTH REFRACTIVE INDEX AND THICKNESS SIMULTANEUSLY. iN TTHIS LETTER, EXPERIMENTAL DATA FROM TWO INTERFEROMETERS ARE ALSO DISCUSSED FOR COMPARISON. ONE WITH AN EXTERNALLY-PUMPED PHASE-CONJUGATE MIRROR ACHIEVED WITH A BSO PHOTOREFRACTIVE CRYSTAL AND ANOTHER ONE WITH CONVENTIONAL MIRRORS. RESULTS SHOW THAT THE PHASE SENSITIVITY OF THE PHASE-CONJUGATE INTEFEROMETER IS NOT SIMPLY TWICE THE CORRESPONDING SENSITIVITY OF THE CONVENTIONAL VERSION. A TECHNIQUE TO ESTIMATE THE REFRACTIVE INDEX AND THICKNESS OF HOMOGENEOUS PLANE PARALLEL DIELECTRIC PLATES IS PROPOSED USING A PHASE-CONJUGATE INTERFEROMETER, IN WHICH COUNTING OF INTERFERENCE FRINGES IS EMPLOYED. THE LIGHT BEAM IMPINGES A TILTED PLATE BEFORE IT ENTERS A PHASE-CONJUGATE INTEFEROMETER, AND COUNT OF THE FRINGES PASSING THROUGH A GIVEN REFERENCE AT THE OBSERVING PLANES GIVES THE PHASE CHANGES AS A FUNCTION OF TILTING ANGLE. THE OBTAINED DATA IS FITTED TO A MATHEMATICAL MODEL, WHICH LEADS TO THE DETERMINATION OF BOTH REFRACTIVE INDEX AND THICKNESS SIMULTANEUSLY. iN TTHIS LETTER, EXPERIMENTAL DATA FROM TWO INTERFEROMETERS ARE ALSO DISCUSSED FOR COMPARISON. ONE WITH AN EXTERNALLY-PUMPED PHASE-CONJUGATE MIRROR ACHIEVED WITH A BSO PHOTOREFRACTIVE CRYSTAL AND ANOTHER ONE WITH CONVENTIONAL MIRRORS. RESULTS SHOW THAT THE PHASE SENSITIVITY OF THE PHASE-CONJUGATE INTEFEROMETER IS NOT SIMPLY TWICE THE CORRESPONDING SENSITIVITY OF THE CONVENTIONAL VERSION.