Continuously adjustable multimode optical fiber attenuator

Abstract

The invention discloses a continuously adjustable multimode optical fiber attenuator, which consists of a multimode optical fiber input collimator, a multimode optical fiber output collimator, an attenuation light path and a stepping motor, wherein the attenuation light path consists of a first reflecting mirror, a cylindrical mirror, a linearly gradual change neutral density optical filter and asecond reflecting mirror. When the attenuator works, the stepping motor drives the first reflecting mirror to rotate, a light beam reflected from the first reflecting mirror is injected to different positions on the neutral density optical filter after passing through the cylindrical mirror. Since the rotation angle of the reflecting mirror is continuously adjustable, the injection positions on the optical filter are continuously adjustable so as to generate a continuously adjustable attenuation amount; and a light beam transmitted from the optical filter is reflected by the second reflectingmirror to pass through the neutral density optical filter and the cylindrical mirror again, and after the light beam is reflected by the first reflecting mirror, the light beam is received by the multimode optical fiber output collimator and is output. The attenuator is based on the linearly gradual change neutral density optical filter, the rotary stepping motor is adopted to drive the reflectingmirror, and therefore, the attenuator has the advantages of compact structure and high tuning speed.

Description

technical field [0001] The invention belongs to the field of optical fiber communication, and more specifically relates to a continuously adjustable multimode optical fiber attenuator. Background technique [0002] As an optical passive device, the adjustable optical fiber attenuator can be used in the fields of optical power balance in optical fiber communication systems and modules, calibration and correction of optical fiber instruments, etc. [0003] According to its working principle, fiber optic attenuators can be mainly divided into the following categories. [0004] Longitudinal air isolation technology: An air gap is added between two optical fibers. The light beam emitted from the input fiber cannot be fully received by the output fiber due to divergence, which will attenuate the optical signal. The attenuation can be controlled by the size of the air gap. Based on this principle, a flange-type fixed optical fiber attenuator can be made, and the air gap can be adj...

AI Technical Summary

Problems solved by technology

[0010] Aiming at the deficiencies of the prior art, the object of the present invention is to provide a continuously adjustable multimode fiber attenuator with a compact structure and fast tuning speed, aiming to solve the problem of using a linear stepper motor to drive a linear gradient of the optical density in the prior art. Strip filter to achieve energy attenuation leads to problems of large device size and slow tuning speed

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