Abstract: A method of calibrating a collimating lens system includes transmitting, using an optical transmitter, a beam out of an optical fiber and through a collimating lens of the collimating lens system. The beam is reflected off a perfect flat mirror positioned at an output of the collimating lens and back towards the collimating lens, and received, via the collimating lens, at a power meter connected to the optical fiber. The method also includes adjusting a position of a tip of the optical fiber proximal to the collimating lens while tracking a power reading using the power meter, selecting a calibration position of the optical fiber corresponding to a highest power reading, and securing the optical fiber relative to the collimating lens using the calibration position.

Abstract: The disclosure provides for a free-space optical communication system that includes a first lens group, a field corrector lens, and a second lens group. The first lens group is configured to receive light received from a remote free-space optical transmitter. The first lens group has a first focal plane. The field corrector lens is positioned between the first lens group and the first focal plane of the first lens group and positioned closer to the first focal plane than the first lens group. The first lens group also is made of material having an index of refraction of at least 2.0, and has a second focal plane. The second lens group is positioned at the second focal plane of the field corrector lens and is configured to couple light to a sensor.

Abstract: A method of calibrating a collimating lens system includes transmitting, using an optical transmitter, a beam out of an optical fiber and through a collimating lens of the collimating lens system. The beam is reflected off a perfect flat mirror positioned at an output of the collimating lens and back towards the collimating lens, and received, via the collimating lens, at a power meter connected to the optical fiber. The method also includes adjusting a position of a tip of the optical fiber proximal to the collimating lens while tracking a power reading using the power meter, selecting a calibration position of the optical fiber corresponding to a highest power reading, and securing the optical fiber relative to the collimating lens using the calibration position.

Abstract: Aspects of the disclosure provide an optical communication system. The system may include a receiver lens system configured to receive a light beam from a remote optical communication system and direct the light beam to a photodetector. The system may also include the photodetector. The photodetector may be configured to convert the received light beam into an electrical signal, and the photodetector may be positioned at a focal plane of the receiver lens system. The system may also include a phase-aberrating element arranged with respect to the receiver lens system and the photodetector such that the phase-aberrating element is configured to provide uniform angular irradiance at the focal plane of the receiver lens system.

Abstract: A method of calibrating a collimating lens system includes transmitting, using an optical transmitter, a beam out of an optical fiber and through a collimating lens of the collimating lens system. The beam is reflected off a perfect flat mirror positioned at an output of the collimating lens and back towards the collimating lens, and received, via the collimating lens, at a power meter connected to the optical fiber. The method also includes adjusting a position of a tip of the optical fiber proximal to the collimating lens while tracking a power reading using the power meter, selecting a calibration position of the optical fiber corresponding to a highest power reading, and securing the optical fiber relative to the collimating lens using the calibration position.

Abstract: A method of calibrating a collimating lens system includes transmitting, using an optical transmitter, a beam out of an optical fiber and through a collimating lens of the collimating lens system. The beam is reflected off a perfect flat mirror positioned at an output of the collimating lens and back towards the collimating lens, and received, via the collimating lens, at a power meter connected to the optical fiber. The method also includes adjusting a position of a tip of the optical fiber proximal to the collimating lens while tracking a power reading using the power meter, selecting a calibration position of the optical fiber corresponding to a highest power reading, and securing the optical fiber relative to the collimating lens using the calibration position.

Abstract: A method of calibrating a collimating lens system includes transmitting, using an optical transmitter, a beam out of an optical fiber and through a collimating lens of the collimating lens system. The beam is reflected off a perfect flat mirror positioned at an output of the collimating lens and back towards the collimating lens, and received, via the collimating lens, at a power meter connected to the optical fiber. The method also includes adjusting a position of a tip of the optical fiber proximal to the collimating lens while tracking a power reading using the power meter, selecting a calibration position of the optical fiber corresponding to a highest power reading, and securing the optical fiber relative to the collimating lens using the calibration position.

Abstract: Aspects of the disclosure provide an optical communication system. The system may include a receiver lens system configured to receive a light beam from a remote optical communication system and direct the light beam to a photodetector. The system may also include the photodetector. The photodetector may be configured to convert the received light beam into an electrical signal, and the photodetector may be positioned at a focal plane of the receiver lens system. The system may also include a phase-aberrating element arranged with respect to the receiver lens system and the photodetector such that the phase-aberrating element is configured to provide uniform angular irradiance at the focal plane of the receiver lens system.

Abstract: An optical communication device is provided that includes a first lens having a first surface and a second surface, a second lens having a third surface and a fourth surface, an optical fiber configured to output light including a plurality of ray bundles, and a photodetector located at the fourth surface of the second lens. The first lens is configured to cause the light output from the optical fiber to form an image at an image plane located at the third surface of the second lens. The second lens is configured to cause subsets of the ray bundles received at the third surface of the second lens to intersect or overlap at the photodetector in a smaller cross-sectional area than at the third surface of the second lens.

Abstract: Aspects of the disclosure provide an optical communication system. The system may include a receiver lens system configured to receive a light beam from a remote optical communication system and direct the light beam to a photodetector. The system may also include the photodetector. The photodetector may be configured to convert the received light beam into an electrical signal, and the photodetector may be positioned at a focal plane of the receiver lens system. The system may also include a phase-aberrating element arranged with respect to the receiver lens system and the photodetector such that the phase-aberrating element is configured to provide uniform angular irradiance at the focal plane of the receiver lens system.

Abstract: Aspects of the disclosure provide an optical communication system. The system may include a receiver lens system configured to receive a light beam from a remote optical communication system and direct the light beam to a photodetector. The system may also include the photodetector. The photodetector may be configured to convert the received light beam into an electrical signal, and the photodetector may be positioned at a focal plane of the receiver lens system. The system may also include a phase-aberrating element arranged with respect to the receiver lens system and the photodetector such that the phase-aberrating element is configured to provide uniform angular irradiance at the focal plane of the receiver lens system.

Abstract: An optical communication device is provided that includes a first lens having a first surface and a second surface, a second lens having a third surface and a fourth surface, an optical fiber configured to output light including a plurality of ray bundles, and a photodetector located at the fourth surface of the second lens. The first lens is configured to cause the light output from the optical fiber to form an image at an image plane located at the third surface of the second lens. The second lens is configured to cause subsets of the ray bundles received at the third surface of the second lens to intersect or overlap at the photodetector in a smaller cross-sectional area than at the third surface of the second lens.

Abstract: The disclosure provides for a free-space optical communication system that includes a first lens group, a field corrector lens, and a second lens group. The first lens group is configured to receive light received from a remote free-space optical transmitter. The first lens group has a first focal plane. The field corrector lens is positioned between the first lens group and the first focal plane of the first lens group and positioned closer to the first focal plane than the first lens group. The first lens group also is made of material having an index of refraction of at least 2.0, and has a second focal plane. The second lens group is positioned at the second focal plane of the field corrector lens and is configured to couple light to a sensor.

Abstract: An optical communication terminal is configured to operate in two different complementary modes of full duplex communication. In one mode, the terminal transmits light having a first wavelength and receives light having a second wavelength along a common free space optical path. In the other mode, the terminal transmits light having the second wavelength and receives light having the first wavelength. The terminal includes a steering mirror that directs light to and from a dichroic element that creates different optical paths depending on wavelength, and also includes spatially separated emitters and detectors for the two wavelengths. A first complementary emitter/detector pair is used in one mode, and a second pair is used for the other mode. The system also includes at least two ferrules. Each ferrule operates with a single emitter/detector pair. The ferrules are designed to operate interchangeably with either emitter/detector pair.

Abstract: The disclosure provides for an optical communication device that includes a photodetector, an optical fiber, a first lens, and a second lens. The optical fiber may be configured to relay light. The first lens may include a first surface and a second surface and has an image plane. The first lens may be configured to receive the light output from the optical fiber, where the received light has a first cross-sectional area at the first surface. The second lens may include a third surface positioned at the image plane of the first lens and a fourth surface positioned adjacent to the photodetector. The second lens may be configured to receive the light output from the first lens and to output light having a second cross-sectional area at the fourth surface that is smaller than the first cross-sectional area.

Abstract: A fully-passive optical system creates a counter-propagating reference beam, which may be used to evaluate a misalignment between a receive beam, a transmit beam, and a tracking beam. The system can be mated to a motorized tip-tilt stage, and can measure power of received signals and automatically adjust the tip-tilt stage in response. Thus, the system would always maintain bore-sight with the received beam regardless of mechanical shift over time.

Abstract: The technology relates to the design and placement of beacon transmission optics for free space optical communications (“FSOC”). One aspect of the disclosure provides an FSOC device with a beam steering mechanism, a beam column with a beam expander, an optical bus, and beacon transmission optics. The beacon transmission optics includes a prism that directs outgoing beacon beams into the beam column, and toward the beam steering mechanism. In one embodiment, the outgoing beacon beams do not need to travel through the beam expander of the beam column. As a result, backscatter is minimized and incoming or outgoing beams can be controlled with a single beam-steering mechanism.

Abstract: An optical communication terminal is configured to operate in two different complementary modes of full duplex communication. In one mode, the terminal transmits light having a first wavelength and receives light having a second wavelength along a common free space optical path. In the other mode, the terminal transmits light having the second wavelength and receives light having the first wavelength. The terminal includes a steering mirror that directs light to and from a dichroic element that creates different optical paths depending on wavelength, and also includes spatially separated emitters and detectors for the two wavelengths. A first complementary emitter/detector pair is used in one mode, and a second pair is used for the other mode. The system also includes at least two ferrules. Each ferrule operates with a single emitter/detector pair. The ferrules are designed to operate interchangeably with either emitter/detector pair.

Abstract: An optical communication terminal is configured to operate in two different complementary modes of full duplex communication. In one mode, the terminal transmits light having a first wavelength and receives light having a second wavelength along a common free space optical path. In the other mode, the terminal transmits light having the second wavelength and receives light having the first wavelength. The terminal includes a steering mirror that directs light to and from a dichroic element that creates different optical paths depending on wavelength, and also includes spatially separated emitters and detectors for the two wavelengths. A first complementary emitter/detector pair is used in one mode, and a second pair is used for the other mode. The system also includes at least two ferrules. Each ferrule operates with a single emitter/detector pair. The ferrules are designed to operate interchangeably with either emitter/detector pair.

Abstract: An example beam splitting apparatus is assembled from multiple prisms that are assembled together along respective mating surfaces to form a single monolithic optical device. The beam splitting apparatus includes optical features, such as dichroic and reflective surfaces, that define optical paths for light that enters the beam splitting apparatus. The optical features allow photons in the light to be directed along different optical paths based on their wavelengths. The optical features in the beam splitting apparatus are provided by coatings, films, and/or surface treatments applied to any of the faces of the prisms. In particular, coatings, films, and/or surface treatments are applied to the mating surfaces of the prisms so that the optical features are internal to the assembled monolithic optical device. The beam splitting apparatus may be implemented in a communication terminal that exchanges data modulated light according to frequency-division duplex communications.