HIGH-PRECISION MEASURING METHOD FOR CENTER POSITION OF LIGHT

摘要

PURPOSE:To measure the center position of reflected light from an object with high precision by finding and utilizing the reflection factor rate of a surface to be irradiated to correct a light intensity distribution and approximating the quantized light intensity distribution to a continuous light intensity distribution curve by a minimum square-law method. CONSTITUTION:The object 2 is irradiated with light having uniform light intensity from a reference light source and its reflected light is detected by a visual sensor 3 arranged opposite the object 2. Light intensity obtained at each point is divided by maximum light intensity to find the reflection factor ratio of the surface to be irradiated of the object 2. Then, the object 2 is irradiated with measurement light from a light source 4 for measurement and reflected light at this time is made incident on the sensor 3 to find the light intensity distribution of the reflected light. Then, the light intensity distribution of the reflected light is divided by the reflection factor ratio to correct the influence of nonuniformity of the reflection factor of the surface to be irradiated. Then the light intensity distribution curve which varies continuously is found from the corrected light intensity distribution by using the minimum square- law method to determine the center position of the reflected light.