Testing method, light receiving device, and testing system

A testing method for a ribbon fiber cable comprising optical fibers between a first end face of the ribbon fiber cable and a second end face opposite to the first end face, wherein end faces of the optical fibers are lined up in a single line in a line direction at the first end face, the testing method comprising:

• injecting light into each of the optical fibers at the second end face;
• measuring power of the light exiting from each of the optical fibers at the first end face;
• and
• testing an array of the optical fibers based on the measured power for each of the optical fibers, wherein
• the light is transmitted through a member disposed between the first end face and the second end face, and
• light transmittance of the member monotonically varies in the line direction.

A light receiving device, comprising:

• an adapter connected to a ribbon fiber cable comprising optical fibers, wherein end faces of the optical fibers are lined up in a single line in a line direction at a first end face of the ribbon fiber cable;
• an optical sensor that measures power of light exiting from the ribbon fiber cable connected to the adapter;
• and
• a member that switches between a first state where the member is disposed between the adapter and the optical sensor and a second state where the member is not disposed between the adapter and the optical sensor, wherein
• light transmittance of the member monotonically varies in the line direction.

A testing system for a ribbon fiber cable comprising optical fibers between a first end face of the ribbon fiber cable and a second end face opposite to the first end face, wherein end faces of the optical fibers are lined up in a single line in a line direction at the first end face, the testing system comprising:

• a light emitter that injects light into each of the optical fibers at the second end face;
• an adapter connected to the second end face of the ribbon fiber cable;
• an optical sensor that measures power of the light exiting from the ribbon fiber cable;
• and
• a member that switches a first state where the member is disposed between the adapter and the optical sensor and a second state where the member is not disposed between the adapter and the optical sensor, wherein
• light transmittance of the member monotonically varies in the line direction.

A testing method for a ribbon fiber cable comprising optical fibers between a first end face of the ribbon fiber cable and a second end face opposite to the first end face, wherein end faces of the optical fibers are lined up to form a lines in a line direction at the first end face, the testing method comprising:

• injecting first light into each of the optical fibers at the second end face,
• measuring, with an optical sensor, first power of the first light exiting from each of the optical fibers at the first end face, and
• storing, with a memory, the first power for each of the optical fibers;
• disposing a member between the first end face and the optical sensor, wherein light transmittance of the member monotonically varies in the line direction;
• injecting second light into each of the optical fibers at the second end face;
• measuring, with the optical sensor, second power of the second light exiting from each of the optical fibers at the first end face and causing the second light to be transmitted through the member;
• storing, with the memory, the second power for each of the optical fibers;
• calculating a ratio of the second power to the first power for each of the optical fibers;
• and
• testing an array of the optical fibers based on the calculated ratio.