Abstract: An optical pulse tester includes an optical divider configured to cause a return light to divide into first divided light and second divided light, a first optical receiver configured to receive the first divided light and output a first optical receiver signal, a second optical receiver configured to receive the second divided light and output a second optical receiver signal, and a signal processor configured to obtain a waveform indicating an intensity distribution of the return light in a longitudinal direction of the optical fiber by performing level conversion of the first optical receiver signal and the second optical receiver signal on the basis of a divided ratio of the optical divider and optical receiver sensitivities of the first optical receiver and the second optical receiver and synthesizing the first optical receiver signal and the second optical receiver signal which have been subjected to the level conversion.

Abstract: An optical pulse tester is for testing characteristics of an optical fiber on the basis of return light obtained by causing an optical pulse to be incident on the optical fiber. The optical pulse tester includes a plurality of light source elements configured to emit optical pulses of different wavelength bands, a plurality of light receiving elements provided to correspond to the plurality of light source elements, a first spatial optical system in which the optical pulses emitted from the plurality of light source elements are spatially combined by wavelength to be incident on the optical fiber, and a second spatial optical system in which return light from the optical fiber is spatially separated by wavelength to be incident on the plurality of light receiving elements.

Abstract: A manufacturing method of a body frame includes a pre-strain step of press molding a wavy shape portion in the body frame to apply pre-strain after any press molding to mold the body frame.

Abstract: A manufacturing method of a body frame includes a pre-strain step of press molding a wavy shape portion in the body frame to apply pre-strain after any press molding to mold the body frame.