| 摘要 |
PROBLEM TO BE SOLVED: To provide a projector having a tilt angle measuring device capable of inexpensively measuring a tilt angle in the vertical and/or horizontal direction of a projection surface to the projection optical axis of the projector in order to correct the distortion of a video. SOLUTION: Uniform high-luminance light is projected to the projection surface from the projection lens 21 of a projecting device 20 and passes through one pinhole 51 provided on the front wall surface of the projector 10 at a specified interval from the projected optical axis 27, and reflected light is received by a light intensity measuring sensor 52 arranged at the same interval right and left with the vertically upper part of the optical axis 27 with respect to a reference surface as center on an inside reference line 29. The light intensity of the surrounding environment of the projector 10 is measured by a surrounding environment lightness measuring sensor 55, and a received light intensity analyzing tilt angle calculation part 53 acquires the difference of the light intensity between the right and left sides, combines it with the light intensity of the surrounding environment, obtains the tilt angle between the projection surface 70 and a surface vertical to the optical axis 27 on the reference surface from previously set correlation, and controls an image control part 23 so as to eliminate the distortion of a screen. COPYRIGHT: (C)2005,JPO&NCIPI
|
