Projection type video display apparatus

• Main Authors: YAMASAKI FUTOSHI, YATSU MASAHIKO
• Format: Patent
• Language: English
• Published: 22.05.2007
• Subjects: ACCESSORIES THEREFOR; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USINGWAVES OTHER THAN OPTICAL WAVES; APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FORPROJECTING OR VIEWING THEM; BLASTING; CINEMATOGRAPHY; 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; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; ELECTROGRAPHY; FREQUENCY-CHANGING; FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMSTHEREOF; HEATING; HOLOGRAPHY; LIGHTING; MECHANICAL ENGINEERING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; PHOTOGRAPHY; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHERARTICLES, NOT OTHERWISE PROVIDED FOR; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; WEAPONS

An object of the invention is to achieve a high intensity, a compact structure, a cost reduction and a heat radiation of a liquid crystal panel, in a projection type video display apparatus employing a combination of LED light sources and a light pipe. The light pipe is formed in a hollow type so as to be utilized as a cooling wind path. Further, a permeable or reflective baffle plate is provided within the light pipe. Further, the light pipe is formed by coating a mirror on an inner surface of an optical case integrally formed by fixing optical parts. Further, a dichroic mirror is arranged in an LED light source outgoing surface.