OPTICAL MODULATING DEVICE AND TWO-WAY OPTICAL TRANSMISSION SYSTEM

• Main Authors: FUSE MASARU, FUJITO KATSUYUKI
• Format: Patent
• Language: English
• Published: 20.03.1995
• Edition: 6
• Subjects: DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

PURPOSE:To provide the optical modulating device and two-way optical transmission system which have a small decrease in modulation efficiency and can modulate unidirectionally transmitted light with high efficiency and suppress deterioration in quality due to mutual interference between plural light signals transmitted in opposite directions when used for two-way optical transmission. CONSTITUTION:An optical modulation part 102 is formed of an electrooptic material (e.g. Z-cut plate lithium niobate) whose modulation efficiency depends upon the polarizing direction of incident light, and polarized light adjustment parts 101 and 103 are provided at two input/output ports of the optical modulation part 102; and the 1st polarized light adjustment part 101 adjusts the polarizing direction of the light incident on the optical modulation part 102 to the optical X or Y axis direction of crystal and the 2nd polarized light adjustment part 103 adjusts the polarizing direction of the incident light to the optical Z axis direction of the crystal.