The present invention relates to target acquisition and related devices, and more particularly to telescopic gunsights and associated equipment used to achieve shooting accuracy at, for example, close ranges, medium ranges and extreme ranges at stationary and moving targets.

A controller (26) of a surveying instrument including a GPS receiver (28) and a transmitter and receiver section (24) for communicating with a prism device including a GPS receiver (58), an atmospheric pressure sensor (60), a temperature sensor (32), and a transmitter and receiver section (54) for communicating with the surveying instrument calculates an azimuth angle of the prism device when viewed from the surveying instrument and a distance therebetween from positions of the prism device and surveying instrument obtained from the GPS receivers, further calculates an elevation angle of the prism device when viewed from the surveying instrument from the distance and atmospheric pressures at the positions of the prism device and surveying instrument, and issues a rotation command to a horizontal drive section (16) and a vertical drive section (18), so that a collimating telescope can be immediately and automatically directed toward a reflecting prism for measurement.

A device for determining the result of digit multiplication based-on diagram-configured carrier rotation and transition path is proposed. Firstly, one of three types of visual teaching tools including first type of visual teaching tool, second type of visual teaching tool and third type of visual teaching tool is selected, then, the first type of or the second type of diagram-configured carrier is rotated to determine an initial node, and thereby transferring multiplicand from digit 1 to digits 3, 7, or 9, or transferring multiplicand from digit 2 to digits 4, 6, or 8. Finally, proceeding number (PN) of the first transition paths, the second transition paths or the third transition paths reaching to an object node is determined to obtain a multiplier and product value of the multiplicand and the multiplier.

A device for determining the result of digit multiplication based-on diagram-configured carrier rotation and transition path is proposed. Firstly, one of three types of visual teaching tools including first type of visual teaching tool, second type of visual teaching tool and third type of visual teaching tool is selected, then, the first type of or the second type of diagram-configured carrier is rotated to determine an initial node, and thereby transferring multiplicand from digit 1 to digits 3, 7, or 9, or transferring multiplicand from digit 2 to digits 4, 6, or 8. Finally, proceeding number (PN) of the first transition paths, the second transition paths or the third transition paths reaching to an object node is determined to obtain a multiplier and product value of the multiplicand and the multiplier.