Abstract: In an optical emitter device, when point emitters are placed on the focal plane of a lens system, each individual point emitter will point to a specific free space angle depending on the position of the point emitter relative to the longitudinal central axis of the lens system. Point emitters comprising end-fire tapers combined with both a turning mirror and a micro-lens provide improved performance, because, unlike grating couplers, end-fire tapers enable uniform broadband operation with all possible polarization states. A turning mirror may be added to direct the light emission from the end-fire tapers to vertically upwards, which enables both a two-dimensional point emitter array and a more streamlined assembly process.

Abstract: Optical switch trees are commonly used to route light from one input channel to multiple possible output channels one at a time. As the number of output channels increases, the number of wire-bonding pads increases and the drive electronics becomes more complicated. The optical switch tree comprises an array of optical switches arranged in a plurality of rows of optical switches, each connected by a row bus, which are connected to a first multiplexer and a common power source; and a plurality of columns of optical switches, each connected by a column bus, which are connected to a second multiplexer and a common ground. A control processor selects one of the plurality of columns of optical switches to connect to the common ground, and selects one of the plurality of rows of optical switches to connect to the common power source, thereby selecting a single optical switch in the array of optical switches to activate.

Abstract: An optical phased array comprising a row-column driving mechanism is disclosed that reduces the number of digital to analog converter (DAC) channels to the number of rows N and the total number of interface pin counts down to the number of columns plus the number of rows M+N. Disclosed herein are systems and architecture for thermal waveguide-based phase shifters which improve thermal efficiency by having multi-pass waveguides arranged proximate a heating element in a serpentine fashion, which enables an increase in phase shift without increasing the length or the power consumption of the heating element by increasing the total length of waveguide being heated by a singular heating element.

Abstract: Optical switch trees are commonly used to route light from one input channel to multiple possible output channels one at a time. As the number of output channels increases, the number of wire-bonding pads increases and the drive electronics becomes more complicated. The optical switch tree comprises an array of optical switches arranged in a plurality of rows of optical switches, each connected by a row bus, which are connected to a first multiplexer and a common power source; and a plurality of columns of optical switches, each connected by a column bus, which are connected to a second multiplexer and a common ground. A control processor selects one of the plurality of columns of optical switches to connect to the common ground, and selects one of the plurality of rows of optical switches to connect to the common power source, thereby selecting a single optical switch in the array of optical switches to activate.

Abstract: Optical switch trees are commonly used to route light from one input channel to multiple possible output channels one at a time. As the number of output channels increases, the number of wire-bonding pads increases and the drive electronics becomes more complicated. The optical switch tree comprises an array of optical switches arranged in a plurality of rows of optical switches, each connected by a row bus, which are connected to a first multiplexer and a common power source; and a plurality of columns of optical switches, each connected by a column bus, which are connected to a second multiplexer and a common ground. A control processor selects one of the plurality of columns of optical switches to connect to the common ground, and selects one of the plurality of rows of optical switches to connect to the common power source, thereby selecting a single optical switch in the array of optical switches to activate.

Abstract: Optical switch trees are commonly used to route light from one input channel to multiple possible output channels one at a time. As the number of output channels increases, the number of wire-bonding pads increases and the drive electronics becomes more complicated. The optical switch tree comprises an array of optical switches arranged in a plurality of rows of optical switches, each connected by a row bus, which are connected to a first multiplexer and a common power source; and a plurality of columns of optical switches, each connected by a column bus, which are connected to a second multiplexer and a common ground. A control processor selects one of the plurality of columns of optical switches to connect to the common ground, and selects one of the plurality of rows of optical switches to connect to the common power source, thereby selecting a single optical switch in the array of optical switches to activate.

Abstract: An optical phased array comprising a row-column driving mechanism is disclosed that reduces the number of digital to analog converter (DAC) channels to the number of rows N and the total number of interface pin counts down to the number of columns plus the number of rows M+N. Disclosed herein are systems and architecture for thermal waveguide-based phase shifters which improve thermal efficiency by having multi-pass waveguides arranged proximate a heating element in a serpentine fashion, which enables an increase in phase shift without increasing the length or the power consumption of the heating element by increasing the total length of waveguide being heated by a singular heating element.

Abstract: In an optical emitter device, when point emitters are placed on the focal plane of a lens system, each individual point emitter will point to a specific free space angle depending on the position of the point emitter relative to the longitudinal central axis of the lens system. The plurality of point emitters are arranged in an array comprising a plurality of rows of point emitters and a plurality of columns of point emitters. Each of the plurality of point emitters comprises a grating coupler configured to emit a respective beam of light in a respective transmission direction. Each grating coupler comprises a first plurality of periodically spaced optical waveguide grating structures, at least some of the optical waveguide grating structures including a notch, whereby a first portion of each optical waveguide grating structure extends a different height than a second portion.

Abstract: In an optical emitter device, when point emitters are placed on the focal plane of a lens system, each individual point emitter will point to a specific free space angle depending on the position of the point emitter relative to the longitudinal central axis of the lens system. Point emitters comprising end-fire tapers combined with both a turning mirror and a micro-lens provide improved performance, because, unlike grating couplers, end-fire tapers enable uniform broadband operation with all possible polarization states. A turning mirror may be added to direct the light emission from the end-fire tapers to vertically upwards, which enables both a two-dimensional point emitter array and a more streamlined assembly process.

Abstract: Method and system that utilizes the information contained in a non-THz image to configure the THz image assembly for optimizing the acquired THz image of the objects of interest. By utilizing a non-THz image assembly operated in a frequency range outside the THz illumination range, a non-THz image of objects positioned in a region of interest is acquired. Then, by analyzing the non-THz image, the THz image assembly is configured to have THz image of the objects of interest with better THz image quality provided by correct focusing of the object of interest. Furthermore, the THz source providing the THz illumination also may also be adjusted so that the emitted THz illumination is concentrated on the objects of interest for efficient use of THz energy.

Abstract: Terahertz-gigahertz illuminator that may be implemented in or attached to many gigahertz/terahertz applications or systems (such as imaging, security or communication system) is proposed. One or more THz emitters are combined to form an array, where each emitter is comprised of a THz source and a THz lens. Furthermore, for each THz emitter, the geometric relation between the THz source and the THz lens may be dynamically modified to dynamically modify both the emission angle and the pointing angle of the launched THz wave. In addition, each THz emitter may be rotated and/or translated to change the propagation direction of the launched THz wave. Therefore, the THz illuminator may uniformly illuminate the object of interest at any distance without modifying other aspects of the THz source to effectively use the limited source power provided by the individual THz emitters.

Abstract: Terahertz-gigahertz fisheye lens systems that may be implemented in or attached to many gigahertz/terahertz systems (such as imaging or security system) are proposed. Each proposed terahertz-gigahertz fisheye lens system includes three lens elements in which combined provides a FOV of about 160°. Each lens element is made of quartz or materials having similar refractive indices. The surfaces of each lens element are either planar and/or spherical. Furthermore, the radius of curvature, diameter, surface profile, size, spacing, and material of the lens elements may be selected to achieve quality performance. Also, to change the focusing distance for achieving optimum imaging resolution, the spacing between these lens element and the image sensor (or the object) may be adjusted.

Abstract: The proposed retro-directive quasi-optical system includes at least a lens set and a pixel array. The lens set is positioned on one side of the pixel array and the lens set instantly establishes retro-directive space channels between the pixels in the pixel array and the object(s) distributed in the accessible space defined by the lens set through infinite or finite conjugation. In the pixel array, a number of pixels are arranged as an array and each pixel is composed of at least one pair of transmitter antenna and receiver antenna. To guarantee that the electromagnetic waves transmitted from a pixel into the accessible space may be reflected back to the receiver of the same pixel, the size of each pixel is not larger than the point-spread spot size defined by the lens set, wherein the point-spread spot size can be contributed either from lens diffraction or aberration.

Abstract: The invention discloses a three-dimensional complementary-conducting-strip (CCS) structure. Some two-dimensional mesh metal layers are stacked vertically and connected mutually via numerous vias to form a three-dimensional network structure, and one or more signal lines with three-dimensional trace style(s) are positioned inside and separated away the three-dimensional network structure. Moreover, each two-dimensional mesh metal layer is a planar metal layer with one or more empty areas. The three-dimensional network structure is grounded, the signal lines(s) is electrically connected to the device(s) and/or terminal(s) respectively, and the dielectric material(s) is used to electrically insulate the signal line(s) from the three-dimensional network structure.

Abstract: Lens systems used in a gigahertz/terahertz imaging system are proposed. Each proposed lens system may include two thin lens elements, spherical or aspherical, in which combined provides gigahertz-terahertz refractive power with a small f-number. The gigahertz-terahertz waves are diverted by the lens systems in such a way that it forms an image of an object, such as a human scale object, on a planar gigahertz-terahertz image sensor. The radius of curvatures, profile, sizes, spacing, and aspherical coefficients of the lens elements may be selected to achieve quality focusing performance. The spacing between the lens elements and the spacing between the lens elements and the image sensor may be adjusted to change both the focal length and the focusing distance to achieve optimum field of view and maximum imaging resolution. The size of the lens may be scaled with the size of the object or the lens aperture stop.

Abstract: A THz system has a housing configured to minimize both external noise and internal stray THz waves. The housing material is selected according to the frequency range of THz waves to be propagated though the space enclosed by the housing. In general, the housing is made of foam material, such as low relative dielectric constant foam material, especially foam with conductive additives. The relative dielectric constant of foam material is usually approach to 1.0, which may minimize the reflection of THz waves propagating into the housing. The conductive additives may increase the absorption of the THz waves, even other electromagnetic waves, inside the housing. Clearly, by using proper material, such as Expanded Polypropylene (EPP) and/or Styrofoam, with proper conductive additives, such as graphite, carbon, sliver, absorptive particles/dyes, the housing may minimize the interference of undesired stray terahertz-gigahertz waves, even other noise.

Abstract: The present invention provides an electromagnetic wave receiving/transmitting device and the application thereof. The electromagnetic wave receiving/transmitting device of the present invention can effectively receive up to 80 to 500 GHz of terahertz electromagnetic waves. The electromagnetic wave receiving/transmitting device of the present invention further achieves the application of terahertz imaging. The physical package of the electromagnetic wave receiving/transmitting device of the present invention is capable of effectively absorbing external and internal noise of electromagnetic waves to significantly reduce noise, and thereby achieving the application of terahertz imaging.