An optical system includes a light-guide optical element (LOE) (100) having a pair of parallel major external surfaces (102, 104) and a set of mutually-parallel reflector surfaces (106a, 106b, 106c) obliquely angled within the LOE. At least one of the reflector surfaces has high reflectivity for angles of incidence above 60 degrees to the normal and partial reflectivity for angles of incidence less than 35 degrees to the normal.

A device includes a first lens), a second lens, and an adjustment platform. The first lens is arranged between a first end surface and a second end surface, and enlarges the mode field diameter of light that is guided through a first optical waveguide and is emitted from the first end surface. The second lens is arranged between the first lens and a second end surface, and collects light that has passed through the first lens. The first lens is mounted on the adjustment platform. The distance between the optical axis of the first optical waveguide and the principal point of the first lens is adjusted on a plane orthogonal to the optical axis of the first optical waveguide using the adjustment platform.

A device includes a first lens), a second lens, and an adjustment platform. The first lens is arranged between a first end surface and a second end surface, and enlarges the mode field diameter of light that is guided through a first optical waveguide and is emitted from the first end surface. The second lens is arranged between the first lens and a second end surface, and collects light that has passed through the first lens. The first lens is mounted on the adjustment platform. The distance between the optical axis of the first optical waveguide and the principal point of the first lens is adjusted on a plane orthogonal to the optical axis of the first optical waveguide using the adjustment platform.

There is provided a light emitting element and an optical waveguide that propagates light from the light emitting element. For example, the optical waveguide is an optical fiber or a silicon optical waveguide. The light propagating through the optical waveguide is light having components of a fundamental mode and a first order mode, and the light propagates through the optical waveguide while having a light intensity distribution in which high intensity portions alternately appear in one direction and another direction opposite to the one direction with respect to the center of a core along the optical waveguide. A light intensity distribution at an output end surface of the optical waveguide is a light intensity distribution corresponding to an intermediate position between a first position where the high intensity portion is in the one direction and a second position where the high intensity portion is in the another direction. In a case of propagating the light having the components of the fundamental mode and the first order mode, it is possible to obtain favorable coupling efficiency regardless of a direction of an optical axis deviation, as in a case of propagating light having only the component of the fundamental mode. A cost is thus reduced by reducing accuracy of positional deviation.

Provided is an optical communication device, such as a wavelength locker, a wavelength demultiplexer, an optical coupling system, and an optical switching system, using a small-sized lens element. An optical communication device includes, as a lens element, a liquid crystal diffractive lens element having an optically anisotropic layer that is formed using a composition containing a liquid crystal compound, and has a liquid crystal alignment pattern in which an orientation of an optical axis of the liquid crystal compound changes while continuously rotating toward one direction, in a radial shape from an inside toward an outside, and in the liquid crystal alignment pattern, in a case where a length over which the orientation of the optical axis rotates by 180° in one direction in which the optical axis changes is a single period, a length of the single period gradually decreases from the inside toward the outside.

Provided is an optical communication device, such as a wavelength locker, a wavelength demultiplexer, an optical coupling system, and an optical switching system, using a small-sized lens element. An optical communication device includes, as a lens element, a liquid crystal diffractive lens element having an optically anisotropic layer that is formed using a composition containing a liquid crystal compound, and has a liquid crystal alignment pattern in which an orientation of an optical axis of the liquid crystal compound changes while continuously rotating toward one direction, in a radial shape from an inside toward an outside, and in the liquid crystal alignment pattern, in a case where a length over which the orientation of the optical axis rotates by 180° in one direction in which the optical axis changes is a single period, a length of the single period gradually decreases from the inside toward the outside.

This application provides an optical switching apparatus. Input ports are configured to input a first beam into a dispersion assembly at a first angle of incidence in a first direction, the input ports are further configured to input a second beam into the dispersion assembly at a second angle of incidence in the first direction, and a difference between absolute values of the first angle of incidence and the second angle of incidence is not zero. The difference between the absolute values of the first angle of incidence and the second angle of incidence enables a first region in which spots of the first beam are arranged and a second region in which spots of the second beam are arranged to be separated from each other in the first direction, and enables the first region and the second region to at least partially overlap in a second direction.

This application provides an optical switching apparatus. Input ports are configured to input a first beam into a dispersion assembly at a first angle of incidence in a first direction, the input ports are further configured to input a second beam into the dispersion assembly at a second angle of incidence in the first direction, and a difference between absolute values of the first angle of incidence and the second angle of incidence is not zero. The difference between the absolute values of the first angle of incidence and the second angle of incidence enables a first region in which spots of the first beam are arranged and a second region in which spots of the second beam are arranged to be separated from each other in the first direction, and enables the first region and the second region to at least partially overlap in a second direction.

A fiber optics rotary joint (FORJ) connects a system console to a probe having a rotatable core, and transfers rotational motion to the probe core. The FORJ comprises a stationary optical fiber in optical communication with a rotatable optical fiber, a motor having a hollow shaft, and a fiber connector attached to a distal end of the hollow shaft. The motor is configured to rotate the rotatable optical fiber relative to the stationary optical fiber. The rotatable fiber is attached to the proximal end of the hallow shaft and connected to the fiber connector. The distal end of the stationary optical fiber is directly opposed to and aligned with the proximal end of the rotatable optical fiber such that optical axes of the stationary and rotatable optical fibers are substantially collinear with the rotational axis of the motor. The fiber connector transfers optical power and torque to the probe core.

A fiber optics rotary joint (FORJ) connects a system console to a probe having a rotatable core, and transfers rotational motion to the probe core. The FORJ comprises a stationary optical fiber in optical communication with a rotatable optical fiber, a motor having a hollow shaft, and a fiber connector attached to a distal end of the hollow shaft. The motor is configured to rotate the rotatable optical fiber relative to the stationary optical fiber. The rotatable fiber is attached to the proximal end of the hallow shaft and connected to the fiber connector. The distal end of the stationary optical fiber is directly opposed to and aligned with the proximal end of the rotatable optical fiber such that optical axes of the stationary and rotatable optical fibers are substantially collinear with the rotational axis of the motor. The fiber connector transfers optical power and torque to the probe core.