Abstract: An optical waveguide, for use a near-eye or heads-up display system, includes an input-coupler, an intermediate-component and an output-coupler. The input-coupler is configured to couple light corresponding to an image that is incident on the input-coupler, into the optical waveguide and towards the intermediate-component. The intermediate-component can be implemented as a Bragg polarization grating that comprises a stack of birefringent layers configured to diffract the light corresponding to the image that is incident thereon into a zero-order beam having one of right handed circular polarization or left handed circular polarization, and a first-order beam having the other one of right handed circular polarization or left handed circular polarization.

Abstract: An optical waveguide, for use a near-eye or heads-up display system, includes an input-coupler, an intermediate-component and an output-coupler. The input-coupler is configured to couple light corresponding to an image that is incident on the input-coupler, into the optical waveguide and towards the intermediate-component. The intermediate-component can be implemented as a Bragg polarization grating that comprises a stack of birefringent layers configured to diffract the light corresponding to the image that is incident thereon into a zero-order beam having one of right handed circular polarization or left handed circular polarization, and a first-order beam having the other one of right handed circular polarization or left handed circular polarization.

Abstract: A transparent waveguide for use in eye tracking includes an input-coupler and an output-coupler. The input-coupler comprises a plurality of curved grating lines having a radially varying pitch. When positioned in front of an eye illuminated with infrared light, infrared light beams reflected from the eye and incident on the input-coupler enter the waveguide at the input-coupler, propagate through the waveguide by way of total internal reflections, and exit the waveguide proximate the output-coupler.

Abstract: A transparent waveguide for use in eye tracking includes an input-coupler and an output-coupler. The input-coupler comprises a plurality of curved grating lines having a radially varying pitch. When positioned in front of an eye illuminated with infrared light, infrared light beams reflected from the eye and incident on the input-coupler enter the waveguide at the input-coupler, propagate through the waveguide by way of total internal reflections, and exit the waveguide proximate the output-coupler.

Abstract: A transparent waveguide, for use in tracking an eye illuminated by infrared light, includes an input-coupler and an output-coupler. The input-coupler includes a stack of electronically switchable diffractive gratings arranged parallel to one another, each of which has a respective lens power that causes each of the gratings in the stack to have a different focal length. Each grating, when turned on, couples received infrared light into the waveguide. A sensor images an eye in dependence on infrared light beams that exit the waveguide at the output-coupler. Images of an eye, obtained using the sensor, are analyzed to determine which one of the electronically switchable diffractive gratings, when turned on, provides a best focused image of the eye or portion thereof. The one of the electronically switchable diffractive gratings, which provides the best focused image of the eye, is used for imaging the eye during eye tracking.

Abstract: A transparent waveguide for use in eye tracking includes an input-coupler and an output-coupler. The input-coupler comprises a plurality of curved grating lines having a radially varying pitch. When positioned in front of an eye illuminated with infrared light, infrared light beams reflected from the eye and incident on the input-coupler enter the waveguide at the input-coupler, propagate through the waveguide by way of total internal reflections, and exit the waveguide proximate the output-coupler.

Abstract: A transparent waveguide, which is for use in tracking an eye that is illuminated by infrared light having an infrared wavelength, includes a volume Bragg grating type of input-coupler adapted to receive infrared light having the infrared wavelength and couple the received infrared light into the waveguide. The volume Bragg grating includes a lower boundary and an upper boundary that is closer to the output-coupler than the lower boundary. A k-vector angle of the volume Bragg grating at the lower boundary is greater than a k-vector angle at the upper boundary, with k-vector angles of the volume Bragg grating between the lower and upper boundaries gradually decreasing as distances decrease between grating planes of the volume Bragg grating and the upper boundary. Additionally, the volume Bragg grating preferably has an angular bandwidth that is no greater than 5 degrees.

Abstract: A transparent waveguide, for use in tracking an eye illuminated by infrared light, includes an input-coupler and an output-coupler. The input-coupler includes a stack of electronically switchable diffractive gratings arranged parallel to one another, each of which has a respective lens power that causes each of the gratings in the stack to have a different focal length. Each grating, when turned on, couples received infrared light into the waveguide. A sensor images an eye in dependence on infrared light beams that exit the waveguide at the output-coupler. Images of an eye, obtained using the sensor, are analyzed to determine which one of the electronically switchable diffractive gratings, when turned on, provides a best focused image of the eye or portion thereof. The one of the electronically switchable diffractive gratings, which provides the best focused image of the eye, is used for imaging the eye during eye tracking.

Abstract: A transparent waveguide, which is for use in tracking an eye that is illuminated by infrared light having an infrared wavelength, includes a volume Bragg grating type of input-coupler adapted to receive infrared light having the infrared wavelength and couple the received infrared light into the waveguide. The volume Bragg grating includes a lower boundary and an upper boundary that is closer to the output-coupler than the lower boundary. A k-vector angle of the volume Bragg grating at the lower boundary is greater than a k-vector angle at the upper boundary, with k-vector angles of the volume Bragg grating between the lower and upper boundaries gradually decreasing as distances decrease between grating planes of the volume Bragg grating and the upper boundary. Additionally, the volume Bragg grating preferably has an angular bandwidth that is no greater than 5 degrees.

Abstract: A classroom response system is disclosed, comprising a classroom response system (CRS) server, at least one instructor console, and at least one student console. The CRS server includes a plurality of software modules, including a runtime server, a master server, a simulator, a query editor, a report generator, a report editor, a seating chart tool, and a simulator. An optional secondary instructor console may be provided, for example for use by a instructor's assistant. In use, the instructor may use the CRS to keep track of attendance, pose questions to students, and receive answers, including open-ended answers. Students may also be allowed to evaluate one another's work. The instructor may display aggregated answers and other anonymous data.

Abstract: A transparent waveguide for use in eye tracking includes an input-coupler and an output-coupler. The input-coupler comprises a plurality of curved grating lines having a radially varying pitch. When positioned in front of an eye illuminated with infrared light, infrared light beams reflected from the eye and incident on the input-coupler enter the waveguide at the input-coupler, propagate through the waveguide by way of total internal reflections, and exit the waveguide proximate the output-coupler.

Abstract: A system for detecting a position of an object such as a surgical tool in an image guidance system includes a camera system with a detection array for detecting visible light a processor arranged to analyze the output from the array. Each object to be detected carries a single marker with a pattern of contrasted areas of light and dark intersecting at a specific single feature point thereon. The pattern includes components arranged in an array around the specific location arranged such that the processor is able to detect an angle of rotation of the pattern around the location and which are different from other markers of the system such that the processor is able to distinguish each marker from the other markers.

Abstract: A classroom response system is disclosed, comprising a classroom response system (CRS) server, at least one instructor console, and at least one student console. The CRS server includes a plurality of software modules, including a runtime server, a master server, a simulator, a query editor, a report generator, a report editor, a seating chart tool, and a simulator. An optional secondary instructor console may be provided, for example for use by a instructor's assistant. In use, the instructor may use the CRS to keep track of attendance, pose questions to students, and receive answers, including open-ended answers. Students may also be allowed to evaluate one another's work. The instructor may display aggregated answers and other anonymous data.

Abstract: A patient table for a common imaging system including Magnetic Resonance and X-Ray retains the patient stationary in position prior to, during and subsequent to the imaging and includes a base, a patient support portion cantilevered from the base and a mattress. A safety system is provided for controlling the operation of the magnet and MR system and the X-Ray systems to allow effective safe operation and controls the movement of the magnet to the table and the movement of the X-Ray imaging systems to and from the table to locations where they do not interfere with the MR imaging.

Abstract: A patient table for a common imaging system including Magnetic Resonance and X-Ray retains the patient stationary in position prior to, during and subsequent to the imaging and includes a base, a patient support portion cantilevered from the base and a mattress. A safety system is provided for controlling the operation of the magnet and MR system and the X-Ray systems to allow effective safe operation and controls the movement of the magnet to the table and the movement of the X-Ray imaging systems to and from the table to locations where they do not interfere with the MR imaging.

Abstract: A patient table for a common imaging system including Magnetic Resonance and X-Ray retains the patient stationary in position prior to, during and subsequent to the imaging and includes a base, a patient support portion cantilevered from the base and a mattress. A safety system is provided for controlling the operation of the magnet and MR system and the X-Ray systems to allow effective safe operation and controls the movement of the magnet to the table and the movement of the X-Ray imaging systems to and from the table to locations where they do not interfere with the MR imaging.

Abstract: A system for detecting a position of an object such as a surgical tool in an image guidance system includes a camera system with a detection array for detecting visible light a processor arranged to analyze the output from the array. Each object to be detected carries a single marker with a pattern of contrasted areas of light and dark intersecting at a specific single feature point thereon. The pattern includes components arranged in an array around the specific location arranged such that the processor is able to detect an angle of rotation of the pattern around the location and which are different from other markers of the system such that the processor is able to distinguish each marker from the other markers.

Abstract: Automatic registration of an MR image is carried out in an image guidance system by placing MR visible markers at known positions relative to markers visible in a camera tracking system. The markers are carried on a common fixture which is attached to a head clamp together with a reference marker which is used when the markers are covered or removed. The tracking system includes a camera with a detection array for detecting visible light a processor arranged to analyze the output from the array. Each object to be detected carries a single marker with a pattern of contrasted areas of light and dark intersecting at a specific single feature point thereon with an array around the specific location to allow the processor is able to detect an angle of rotation of the pattern and to distinguish each marker from the other markers.

Abstract: Image guidance on a computer screen in the patient's vascular system with reduced use of toxic contrast agent and X-ray radiation is obtained by providing anatomical and functional images obtained preferably from an MR Imaging system. A fibre optic device which uses strain measurement to provide an image of the shape and location of the fiber is used to provide spatial information of the elongate guide member as it is pushed through the vascular system with this spatial information being registered to the image of the vascular system by registering the location of the fiber/guide in the image prior to insertion using markers visible in the MR image.

Abstract: A patient table for a common imaging system including Magnetic Resonance and X-Ray retains the patient stationary in position prior to, during and subsequent to the imaging and includes a base, a patient support portion cantilevered from the base and a mattress. A safety system is provided for controlling the operation of the magnet and MR system and the X-Ray systems to allow effective safe operation and controls the movement of the magnet to the table and the movement of the X-Ray imaging systems to and from the table to locations where they do not interfere with the MR imaging.