IMAGING POSITION CALCULATION METHOD AND APPARATUS AND RECORD MEDIUM HAVING IMAGING POSITION CALCULATION PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide an imaging position calculator, which permits correct calculation with high accuracy for the imaging position of a light spot on a photo detector with a smaller amount of calculation than before. SOLUTION: A distribution function approximation means is provided to approximate a section, having a given distribution of the quantity of received light in light energy on a photodetector by an arbitrary approximate function and a light spot imaging position detecting means for determining the imaging position of a light spot on the photodetector using the approximate function obtained. The light spot imaging position detecting means has a quantity of received light distribution integral value calculation means for determining the integral value of the distribution of the quantity of received light at the light spot from the approximate function obtained and a quantity of received light distribution weighted integral value calculation means, to determine the weighted integral value of the quantity of received light distribution at the light spot from the approximate function obtained. The quantity of received light distribution integral value calculating means and the quantity of received light distribution weighted integral value calculating means obtain the integral value and the weighted integral value of the quantity of received light distribution at the light spot, by employing an integral approximation directly using the approximate function.