OPTICAL MODULATING DEVICE

• Main Authors: MINOURA KAZUO, USUI MASAYUKI, BABA TAKESHI, SOMEYA ATSUSHI, MATSUOKA KAZUHIKO, MIYAJIMA YUUKO, NISHIMURA YUKIO
• Format: Patent
• Language: English
• Published: 12.07.1985
• 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 obtain modulated light and unmodulated light with simple constitution by utilizing the characteristics of a distributed index type optical modulating element. CONSTITUTION:The optical modulating element M consists of a heat-effect medium which produces a refractive index distribution internally by heat and a heat generating means which supplies heat to the medium, and the generated heat of the means 3 is controlled by a control means. The refractive index distribution is produced at the element M, luminous flux from a light source part is made incident, and the luminous flux passed through the element M is image- formed by an image forming means 13; the luminous flux passed through the refractive index distribution is image-formed at a point P and the luminous flux passed except through the refractive index distribution is image-formed at a point Q. Then a photodetecting medium 14 is provided at the point Q to form a black absent image on the medium 14, but this black absent image is erased unless the heat is generated under the control of a generated heat control means, thus performing optical modulation.