ø

When measuring dimension with a linear CCD sensor without lens, the dimension of a measured object is determined from shadow projected by the object on the sensor. For such measurement the measured object must be illuminated from a light source with known radiation character. A source of parallel beams (light sheet) is usually used. When using such light source, the measured dimension is directly determined by the size of the shadow projected on the sensor. The disadvantage of this light source is its complex construction and high price. This study examines usage of simpler light sources. For example a point light source can be used. When using point light source, the size of the shadow, which the measured object projects on the CCD sensor, is not the same as the dimension of the measured object. This is caused by the divergence of the light beams. The size of the projected shadow must be therefore corrected. This correction depends on the shape of measured object. For example dimension of an object with rectangular section is determined: ( ) p d dnmx ×÷