LIGHTING DEVICE

• Main Authors: MIZUHARA KAZUMI, YAMASHITA TOMOYOSHI
• Format: Patent
• Language: English
• Published: 20.10.2011
• Subjects: BLASTING; 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; HEATING; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21Sand F21V, RELATING TO THEFORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THELIGHT EMITTED; LIGHTING; MECHANICAL ENGINEERING; NON-LINEAR OPTICS; NON-PORTABLE LIGHTING DEVICES; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; SYSTEMS THEREOF; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLEEXTERIORS; WEAPONS

PROBLEM TO BE SOLVED: To provide a lighting device which has a uniform luminance distribution even though irradiated locations are arranged to be separated in a wide area and has high front brightness and is a thin type.SOLUTION: The lighting device includes a light guide body 1 having the refractive index of ng, a prism sheet 3 having a prism layer where a prism train is formed, and an intermediate layer 4 arranged between the light guide body 1 and the prism sheet 3. The intermediate layer 4 has a plurality of discontinuous structures having the refractive index of n1 and formed discontinuously, and a plurality of gaps with the refractive index of n2 (here, n2<n1, and n2<ng). Light incident to the light guide body 1 is transmitted to the prism sheet 3 by passing through the discontinuous structures of the intermediate layer 4, and is guided to an illumination range of the light guide body 1 by being totally reflected with the prism train.