The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 31, 2012
Filed:
Sep. 06, 2007
Tetsuro Shiota, Osaka, JP;
Tetsuro Shiota, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A diaphragm control angle calculating portioncalculates an angle at which a diaphragm is controlled to control an amount of light that reaches from a lampto a display deviceaccording to distribution information of an input video signal, such as the maximum value, the minimum value, the average value and the histogram of the signal, and the control angle is inputted to a fan control signal generating portionand a diaphragm driving portionas control angle information. The diaphragm driving portioncontrols the angle of the diaphragmbased on the control angle information. Light from the lampdriven by a lamp driving portionenters the diaphragm, and the amount of light according to the angle of the diaphragmenters the display device. The fan control signal generating portioncontrols the rotation speed of a cooling fanaccording to a combination of the control angle information and the temperature detected by a temperature sensor. A high-contrast display image can be produced while noise resulting from an increase in the rotation speed of the cooling fan can be suppressed and the reliability of the lamp can be ensured by avoiding the influence of the temperature.