摘要 |
A mask used in a dual pyroelectric sensor and configured to allow the pyroelectric sensor to accurately detect a movement of a moving object in each of the disposition direction of two pyroelectric elements and a direction perpendicular to the disposition direction. The mask is applied to the sensing surface of the dual pyroelectric sensor to increase the sensitivity with which the pyroelectric sensor detects a moving object. The mask includes a sheet configured to block infrared rays and an aperture pattern including through holes formed in the sheet. The aperture pattern is formed in such a manner that the percentages of the respective infrared-irradiated ranges of the two pyroelectric elements of the pyroelectric sensor vary with a movement of a moving object in each of x- and y-directions. |