A rod-type photonic crystal fiber amplifier includes a signal coupling lens, a first dichroic mirror, a first hollow pump coupling lens, and a rod-type photonic crystal fiber. The rod-type photonic crystal fiber comprises a core and a cladding, wherein signal light is coupled into the core of the rod-type photonic crystal fiber through the signal coupling lens, and pump light is coupled into the cladding of the rod fiber through the hollow pump coupling lens. The structure optimizes the coupling between the signal light and the core of the rod-type photonic crystal fiber, and the coupling between the pump light and the cladding of the rod fiber respectively by introducing the hollow pump coupling lens. The purpose of this is to fully optimize the rod-type photonic crystal fiber amplifier, improve the amplification efficiency and improve the efficiency of a manufacturing process.

The present disclosure relates to the field of communication technology, and provides a connector for photoelectric hybrid in free space of magnetic absorption comprising matching a male connector and a female connector and provided with a conductive pin and an electrical contact used for conduction, an optical communication module for optical communication and comprising optical fiber connector and lens capable of expanding the light beam output to each other, a spacing formed between the two lenses, and the male connector and the female connector aligned and remained in a plug-in state through a magnetic field. Furthermore, a guiding structure is provided to embody precise alignment of the lens of the male connector and the lens of the female connector. The connector can transmit both optical signals and electrical signals, and has the characteristics of high processing yield, high reliability, and convenient use.

The present disclosure relates to the field of communication technology, and provides a connector for photoelectric hybrid in free space of magnetic absorption comprising matching a male connector and a female connector and provided with a conductive pin and an electrical contact used for conduction, an optical communication module for optical communication and comprising optical fiber connector and lens capable of expanding the light beam output to each other, a spacing formed between the two lenses, and the male connector and the female connector aligned and remained in a plug-in state through a magnetic field. Furthermore, a guiding structure is provided to embody precise alignment of the lens of the male connector and the lens of the female connector. The connector can transmit both optical signals and electrical signals, and has the characteristics of high processing yield, high reliability, and convenient use.

The present disclosure relates to a sensor module for measuring a displacement occurring in a sensor by a confocal principle, a strain sensor device comprising the same, and a method for measuring a strain in a target using the same. Specifically, the sensor module according to an embodiment of the present disclosure includes a first single-mode optical fiber, a first GRIN optical fiber, a multi-mode optical fiber, a second GRIN optical fiber and a second single-mode optical fiber connected in an axial direction, wherein light inputted through the first single-mode optical fiber is transmitted to the second single-mode optical fiber through the series of optical fibers, and light forming a focal point in the core of the second single-mode optical fiber is detected using a confocal principle.

The present disclosure relates to a sensor module for measuring a displacement occurring in a sensor by a confocal principle, a strain sensor device comprising the same, and a method for measuring a strain in a target using the same. Specifically, the sensor module according to an embodiment of the present disclosure includes a first single-mode optical fiber, a first GRIN optical fiber, a multi-mode optical fiber, a second GRIN optical fiber and a second single-mode optical fiber connected in an axial direction, wherein light inputted through the first single-mode optical fiber is transmitted to the second single-mode optical fiber through the series of optical fibers, and light forming a focal point in the core of the second single-mode optical fiber is detected using a confocal principle.

An optical assembly may comprise an input fiber to provide a beam, a process fiber comprising a ring-shaped outer core surrounded by a cladding, and a first beam shifter arranged to receive the beam from the input fiber and to shift the beam spatially to illuminate the ring-shaped outer core of the process fiber. The optical assembly may further comprise a second beam shifter arranged to receive the beam from the first beam shifter and to add skew to the beam that is launched into the ring-shaped outer core of the process fiber.

A light receiver array according to the present invention is constituted by array-aligning plural receivers having slow light waveguides of photonic crystals, and a LiDAR device according to the present invention is constituted by linearly arranging a light receiver array and a transmitter. An arranging relationship of plural receivers of the light receiver array is an array-like element formed by array-aligning plural receivers having the slow light waveguides of photonic crystals, and the array alignment is defined by alignment for defining a position relationship between the plural receivers constituting the light receiver array, and orientation for defining a direction of each receiver. A relationship p=λ/sin Δθr is satisfied between the alignment pitch p, wavelength λ of the reception light, and an arrival angle Δθr when a phase difference between reception lights received by waveguide ends of adjacent receivers is one wavelength. Such a constitution that the arrival angle Δθr is equal to a widening angle Δθt of radiation light is suitable.

The optical device can comprise a substrate having a first face opposite a second face, a thickness between the first face and the second face, the first face and the second face being planar, the first face being parallel the second face, the substrate being transparent to an electromagnetic radiation in a given spectrum; a planar polarization-dichroic focusing lens covering the first face, the lens having a first focusing power for a first polarization of the electromagnetic radiation and a second focusing power for a second polarization of the electromagnetic radiation, the second focusing power being different from the first focusing power; and a planar polarization-dichroic mirror covering the second face, the mirror being reflective to the first polarization and transparent to the second polarization.

An embodiment optical coupling structure includes: at least one optical element; at least one optical fiber which has an end surface facing the optical element; and an adhesive agent which is applied to at least the end surface and a part of the optical element so as to optically and mechanically couple the optical element and the optical fiber, wherein both a contact angle which a surface of the optical element and a surface of the adhesive agent make and a contact angle which a surface of the optical fiber and the surface of the adhesive agent make are less than 90 degrees. With such a configuration, alignment between the optical element and the optical fiber can be realized by passive alignment so that a mounting time and a mounting cost in coupling the optical element and the optical fiber can be reduced.

In one aspect, an optical system is disclosed. In some embodiments, the optical system includes an optical waveguide, and at least two coupling means forming at least one confocal point being located within the optical waveguide, where a first coupling means of the at least two coupling means has a first focal length, and a second coupling means of the at least two coupling means has a second focal length. In some examples, the first coupling means is configured to couple and/or focus incident light to the optical waveguide, and the second coupling means is configured to emit and/or collimate light conveyed by the optical waveguide.