JPH065305B

PURPOSE:To obtain an accurate optical meteorological value with simple technique by measuring an elevation angle from a reference point to a target point and obtaining the radius of curvature of an optical path by atmospheric refraction in the calculation by a specified formula based on the measured elevation angle. CONSTITUTION:The elevation angle alpha from the reference point to the target point is measured. By taking a geocentric radius on the reference point as R, a height difference of the target point from the reference point as H and an angle made by a line combining the reference point and the center of the earth with a line combining the target point and the center of the earth as phi, the radius of curvature (r) of the optical path can be obtained by the formula. The geocentric radius R, the height difference H and the angle phi can be previously geographically obtained with almost high accuracy respectively. Therefore, the meteorological value continuously varied can be completely considered by measuring the elevation angle alpha every time and using the measured angle in surveying calculation.