公开(公告)号：US07055966B2

公开(公告)日：2006-06-06

申请号：US10682824

申请日：2003-10-10

申请人： Akira Momose ,  Atsushi Miyazawa ,  Keijiro Naito

发明人： Akira Momose ,  Atsushi Miyazawa ,  Keijiro Naito

IPC分类号： G03B21/14 ,  G03B21/16 ,  G03B21/20 ,  G03B21/26 ,  G02B26/02 ,  F21V1/03 ,  H04N5/74

CPC分类号： G03B21/18

摘要： When a video signal is inputted to a projector (10) through a video input terminal, a luminance peak value of an image of the video signal is detected by an image-analyzing circuit (61) to be outputted to a CPU (71). A gain-adjusting circuit (63) adjusts a luminance signal in the video signal based on a command from the CPU (71). The CPU (71) determines a gain adjustment amount based on the luminance peak value of the image obtained by the image-analyzing circuit (61) and outputs the result to the gain-adjusting circuit (63). For instance, when the luminance peak value (Ip) of the image is 50% of the upper limit (Imax) thereof, a gain-adjusting amount AG is doubled. In this case, an illuminating light volume of a light valve (44a) has to be reduced to 50%, which is achieved by light-attenuation by a light-source lamp (21) and an open/close light shield (23).

摘要翻译： 当通过视频输入端子将视频信号输入到投影仪（10）时，由图像分析电路（61）检测视频信号的图像的亮度峰值，以输出到CPU（71）。 增益调整电路（63）根据来自CPU（71）的命令调整视频信号中的亮度信号。 CPU（71）基于由图像分析电路（61）获得的图像的亮度峰值确定增益调整量，并将结果输出到增益调整电路（63）。 例如，当图像的亮度峰值（Ip）为其上限（Imax）的50％时，增益调整量AG增加一倍。 在这种情况下，光阀（44a）的照明光量必须减小到通过光源灯（21）和开闭光屏蔽（23）的光衰减来实现的50％ 。