Detection device and detection method for transmittance and numerical aperture of optical fiber

The invention discloses a device and a method for detecting transmittance and numerical aperture of a light-guide fiber. The device comprises a laser light source, a first optical fiber fixing frame, a first lens group, a second optical fiber fixing frame, a second lens group, an optical power meter and an imaging camera, and the laser light source outputs a test light beam through an emergent optical fiber; the first optical fiber fixing frame is used for fixing the output end of the emergent optical fiber; the distance between the first lens group and the first optical fiber fixing frame is adjustable, and the first lens group is used for shaping a test light beam output by the emergent optical fiber; the second optical fiber fixing frame is used for fixing a to-be-measured optical fiber; the second lens group is used for shaping a test beam output by the to-be-tested optical fiber; the optical power meter is used for acquiring the transmittance of the test light beam passing through the to-be-tested optica