PROJECTION DISPLAY DEVICE

• Main Authors: BESSHO TOMOHIRO, TAKAHASHI MOTOO, OKAMIDO AKIRA, YAMADA AKIHIRO
• Format: Patent
• Language: English
• Published: 15.11.2012
• 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; 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; HOLOGRAPHY; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHOTOGRAPHY; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

PROBLEM TO BE SOLVED: To provide a projection display device easily attaining continuous light quantity control without causing unevenness of illumination of light emitted to a light bulb in response to a video signal, thereby allowing constant image display with satisfactory contrast.SOLUTION: A projection display device comprises: a light bulb 2; a light source 3a for generating light emitted to the light bulb 2; an integrator lens 4 arranged on an optical path between the light source 3a and the light bulb 2 and making uniform illumination distribution of the light emitted from the light source 3a to the light bulb 2; and a light quantity control system 9 arranged on the optical path and including a turning mechanism 9a turning like a pair of double doors in order to adjust the quantity of the light emitted from the light source 3a to the light bulb 2. The turning mechanism 9a is bent in V-shape in a direction to reduce the quantity of light (to block the light).