Three-dimensional image scanner and heat-insulating device for optical apparatus

Abstract

In a three-dimensional image scanner, a grating projection type moire topography is used, so as to capture three-dimensional form information of an object to be measured easily in a short time with a high degree of freedom in measurement. Also, a heat-insulating partition comprising at least two partition walls forming a cooling/heat-insulating path is disposed between a light source and a heat-sensitive section, so as to effectively inhibit the heat generated by the light source from being transmitted to the heat-sensitive section. The three-dimensional form information of the object is captured by a measurement head having a function as a grating projection type moire device. As a consequence, a reference grating such as that in a grating shadow type moire device is unnecessary, and it will be sufficient if a virtual reference grating surface is set at a position conjugate with both of a projection grating and an observation reference grating , whereby the size of the measurable object would not be restricted, and the object can be disposed fore and aft through the virtual reference grating surface. A first partition wall is disposed so as to separate a projection lamp and an illumination lamp from a CCD camera , and a second partition wall is disposed on the side of the lamps , so as to form a cooling passage for guiding the heat generated by both lamps to a cooling fan . As a consequence, heat insulation is attained between the lamps and the CCD camera , and the temperature rise of the partition wall is suppressed. Further, a cooling fan and a third partition wall are disposed on the side of the CCD camera with respect to the first partition wall , so as to form an exhaust heat-insulating path . As a consequence, heat is effectively inhibited from being transmitted to the CCD camera via the first partition wall