Patent ID: 6924474
Filing Date: 2005-08-02
Classification: G01J,G02B,H04N

Abstract:
1. A light leakage detecting device of an optical transmission system using a fiber optic cable, which is used in an optical transmission system, in which a fiber-coupled LD light source having at least a fiber coupling plug mounted at an output end thereof and outputting high-power light from an end of the fiber coupling plug, and a fiber optic cable connected via a connector to the fiber coupling plug and guiding the high-power light to a predetermined position are provided, and the high-power light is outputted from a light guiding end of the fiber optic cable, and for detecting light leakage in the optical transmission system, said device comprising: a light-quantity detector for detecting a quantity of light outputted from the light guiding end; an output control section which switches an output of the fiber-coupled LD light source between a normal level corresponding to an operating state of the optical transmission system and a light-leakage detection level corresoonding to a light-leakage testing state of the optical transmission system, which is lower than the normal level; a light-leakage detection level setting section for setting the light-leakage detection level based on output characteristics of the fiber-coupled LD light source; a light-leakage detection threshold storing and setting section which sets and stores therein a light-leakage detection threshold based on the output characteristics of the fiber-coupled LD light source; a comparing section for comparing a detected output value of the fiber-coupled LD light source controlled by the output control section at the light-leakage detection level, and the threshold stored in the light-leakage detection threshold storing section; and a determining section for determining, based on a comparison result of the comparing section, whether light leakage occurs or not.