Optics: image projectors – Temperature control – Blower
Patent
1997-02-21
1999-12-28
Dowling, William C.
Optics: image projectors
Temperature control
Blower
353 60, G03B 2116
Patent
active
060072059
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a projection display apparatus for separating a white light beam from a light source into three colored light beams, specifically red, blue, and green, passing each of these colored light beams through a light valve composed of a liquid crystal panel for modulation according to the image information, and then after modulation recombining the modulated light beams of each color through a projection lens for projection enlargement to a screen. More specifically, the present invention relates to a cooling mechanism for efficiently cooling the heat-emitting components of such a projection display apparatus.
DESCRIPTION OF THE RELATED ART
A projection display apparatus basically comprises a light source lamp unit; an optical lens unit for optically processing the white light beam emitted from the light source lamp unit to synthesize a color image according to the image information; a projection lens unit for projecting the light beam combined by the optical lens unit to a screen; a power supply unit; and a circuit board group on which the control circuitry, etc., is mounted.
Except for the projection lens unit, each of these components is housed inside the apparatus' outside case. The projection lens unit is generally mounted projecting from the front of the apparatus. An operating panel with the power switch, etc., a receptor window for the remote control, and an input/output terminal group for exchanging signals with an external device, are positioned on the front of the outside case.
A cooling mechanism for cooling internal heat sources such as the light source lamp unit and power supply unit is also built in to this type of projection display apparatus. In general, outside air is introduced through an intake opening in the outside case using an intake fan, and flows over the internal heat-emitting components to cool them. After cooling each of these parts, the outside air conducted inside the apparatus is vented by an exhaust fan to the ambient environment from an air vent opening in the outside case.
The heat-emitting components include each of the optical elements constituting the optical lens unit. More specifically, the liquid crystal light valve and polarizing plate, etc., absorb part of the passed light, and must therefore be sufficiently cooled to prevent overheating. Part of the outside air conducted into the apparatus is therefore directed to the heat-emitting components of the optical lens unit to also cool those components.
However, when air is introduced from outside the apparatus, dust and other foreign matter may also penetrate to the inside of the apparatus. An air filter is, of course, placed over the intake opening to capture dust and filter the air, but it is still possible for fine particulates to penetrate to the inside of the apparatus. When such particulates enter the inside of the apparatus with the outside air and pass over the surface of the optical elements inside the optical lens unit, the particulate may adhere to the surface of the optical elements. When particulate matter thus adheres, the particulate may also be projection enlarged, resulting in an image where the particulate matter is present may be blurred, and image quality deteriorates severely. It is therefore necessary to cool the optical elements inside the optical lens unit in a way that prevents particulate penetration.
However, a mechanism having a dustproof function and capable of efficiently cooling the optical elements inside the optical lens unit has not heretofore been proposed.
DISCLOSURE OF THE INVENTION
The object of the present invention is to provide a projection display apparatus comprising a cooling mechanism capable of efficiently cooling each of the components inside the optical lens unit without causing penetration of dust and particulate.
To achieve this object in a projection display apparatus comprising a light source lamp unit, an optical lens unit for optically processing the white light beam emitted from the light source lamp unit to
REFERENCES:
patent: 3187173 (1965-06-01), Foley
patent: 3748033 (1973-07-01), Harvey
patent: 4787737 (1988-11-01), Ogawa et al.
patent: 5170195 (1992-12-01), Akiyama et al.
patent: 5287132 (1994-02-01), Suzuki et al.
patent: 5418586 (1995-05-01), Fujimori et al.
patent: 5651599 (1997-07-01), Fujimori et al.
patent: 5692821 (1997-12-01), Rodriguez, Jr. et al.
patent: 5738427 (1998-04-01), Booth et al.
patent: 5772300 (1998-06-01), Kitai
patent: 5803566 (1998-09-01), Ogino
Dowling William C.
Gabrik Michael T.
Seiko Epson Corporation
LandOfFree
Optical lens unit having internalized fan unit and projection ap does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Optical lens unit having internalized fan unit and projection ap, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical lens unit having internalized fan unit and projection ap will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2377736