Patent ID: 8781264

Claim:
An optical pulse test apparatus comprising: a light source which emits an optical pulse; a connector to which a test-target optical transmission path of an optical fiber is connected; an optical receiver; an optical coupler which receives the optical pulse emitted from the light source, emits the optical pulse to the connector, receives return light from the optical fiber through the connector, and enters return light into the optical receiver; an operation unit; a display unit; and a signal processing unit which receives an output of the optical receiver, continuously acquires data regarding the intensity of the return light entering the optical receiver, obtains the transmission characteristic of the test-target optical fiber with respect to distance on the basis of data and test parameters designated by the operation unit, and displays the transmission characteristic on the display unit, wherein the light source and the optical coupler, the optical coupler and the connector, and the optical coupler and the optical receiver are respectively connected to each other by optical paths (Fa to Fc) using a single-mode fiber, the signal processing unit includes fiber type designation means for designating, based on the test parameters, the type of the test-target optical fiber as either a single-mode fiber or a multimode fiber, SMF parameter designation means for, when a single-mode fiber is designated by the fiber type designation means, designating parameters including the refractive index of the single-mode fiber, the parameters being necessary for testing an optical transmission path using the single-mode fiber, and mMF parameter designation means for, when a multimode fiber is designated by the fiber type designation means, designating parameters including the refractive index of the multimode fiber, the parameters being necessary for testing an optical transmission path using the multimode fiber, and when the single-mode fiber is designated, the transmission characteristic of the optical fiber with respect to distance is obtained on the basis of intensity data of return light and the parameters including the refractive index designated by the SMF parameter designation means, and when the multimode fiber is designated, the transmission characteristic of the optical fiber with respect to distance is obtained on the basis of intensity data of return light and the parameters including the refractive index designated by the MMF parameter designation means, wherein the signal processing unit includes connection confirmation means for obtaining a connection loss of the test-target optical fiber to the connector and for determining whether or not the connection loss is within an allowable range set in advance, and allowable range shift means for shifting the allowable range to be used for the determination by the connection confirmation means in accordance with a difference of an optical fiber designated by the fiber type designation means.