Answer: Linear induction synchronizers are mainly used to measure B. Line displacement.
Answer analysis:
Induction synchronizers are displacement detection elements that use the principle of electromagnetic induction to convert the relative displacement between two planar windings into electrical signals.
According to their uses and structural characteristics, induction synchronizers can be divided into two categories: linear and rotary.
Linear induction synchronizers consist of a fixed scale and a sliding scale, and are used to measure linear displacement. They are widely used in mechanical equipment, especially in the fields of digital display of displacement, automatic positioning, and numerical control of machine tools.
In contrast, rotary induction synchronizers consist of a stator and a rotor, and are used to measure angular displacement. They are often used in the positioning of radar antennas, precision turntables of machine tools, and other rotary servo systems.
Therefore, for the options in this question:
A. Angular displacement: This is the main measurement object of rotary induction synchronizers, not the main purpose of linear induction synchronizers.
B. Linear displacement: This is the main measurement object of linear induction synchronizers, and it works by detecting the relative linear displacement between a fixed scale and a sliding scale.
C. Both are possible: This option is inaccurate because linear induction synchronizers are specifically designed to measure linear displacement, not angular displacement.
In summary, linear induction synchronizers are mainly used to measure linear displacement, so the correct answer is B.