571 results about "Visual axis" patented technology

A gaze direction determining system and method is provided. A two-camera system may detect the face from a fixed, wide-angle camera, estimates a rough location for the eye region using an eye detector based on topographic features, and directs another active pan-tilt-zoom camera to focus in on this eye region. A eye gaze estimation approach employs point-of-regard (PoG) tracking on a large viewing screen. To allow for greater head pose freedom, a calibration approach is provided to find the 3D eyeball location, eyeball radius, and fovea position. Both the iris center and iris contour points are mapped to the eyeball sphere (creating a 3D iris disk) to get the optical axis; then the fovea rotated accordingly and the final, visual axis gaze direction computed.

A method is provided for increasing the depth of focus of an eye of a patient. A visual axis of the eye is aligned with an instrument axis of an ophthalmic instrument. The ophthalmic instrument has an aperture through which the patient may look along the instrument axis. A first reference target is imaged on the instrument axis at a first distance with respect to the eye. A second reference target is imaged on the instrument axis with the ophthalmic instrument at a second distance with respect to the eye. The second distance is greater than the first distance. Movement is provided such that the patient's eye is in a position where the images of the first and second reference targets appear to the patient's eye to be aligned. A mask comprising a pin-hole aperture having a mask axis is aligned with the instrument axis such that the mask axis and the instrument axis are substantially collinear. The mask is applied to the eye of the patient while the alignment of the mask axis and the instrument axis is maintained. Maintaining alignment of the mask axis and the instrument axis may be facilitated by capturing an image of the eye.

An improved imaging system includes a memory-storage unit, a multiple-dimensional image processor configured to convert information within a multiple-dimensional data set to a two-dimensional representation in a plane orthogonal to an operator-identified view axis, and an image-rendering device configured to display the two-dimensional representation of a volume-of-interest contained within the three-dimensional data set, wherein the two-dimensional representation is responsive to pixel values associated with a faceplate orthogonal to the view axis. A method for viewing information includes identifying a view axis that intersects a multiple-dimensional data set, modifying the multiple-dimensional data set to align the multiple-dimension data set responsive to the view axis, locating a portion of a structure-of-interest along a vector parallel to view axis, associating a set of pixels with a faceplate, and generating a composite view in accordance with the faceplate.

Motion sensing of a portable device using two cameras. A first camera is directed along a first viewing axis and a second camera is directed along a second viewing axis, different from the first viewing axis. The second viewing axis can be substantially opposite the first viewing axis. A motion processing module determines changes in images from the first camera and changes in images from the second camera. The motion processing module compares the direction of change determined from the first camera images relative to the direction of change determined from the second camera images. The motion processing module determines the motion of the portable device based in part on the comparison.

The invention provides a light-type triaxial ISP (inertially stabilized platform) system using an aerial remote sensing technology, comprising a base, four linear vibration dampers, a rolling framework, a pitching framework, a direction framework, two MEMS (micro-electromechanical system) accelerometers, three MEMES gyroscopes, three DC (direct current) brushless torque motors, three sets of reduction gears, three photoelectric encoders and three framework servo control circuits, wherein the base is connected with a plane by the four linear vibration dampers so as to separate linear vibration; the rolling framework and the pitching framework are used for tracking the local geographical level and rotate around the X axis and the Y axis respectively; and the direction framework is used for tracking heading and rotates around the Z axis. The control part drives the three DC brushless motor frameworks to carry out compensation isolation on angular motion of the plane in accordance with angular rate information of the frameworks provided by the three MEMS gyroscopes and attitude information provided by a POS (position and orientation system) or the two EMES accelerators. The light-type triaxial ISP system has the characteristics of high accuracy, high load bearing/self weight ratio, wide stable range, small volume and light weight as well as self-attitude reference, and is suitable for stabilizing the camera visual axis in light-small type aerial remote sensing systems.

The invention discloses a 3D free head moving type gaze tracking system belonging to the technical field of image processing and pattern recognition. The 3D free head moving type gaze tracking system is realized by using the method comprising the steps of: calibration of camera internal parameters, the establishment of a hardware system, the extraction of the center calibrates of pupils in images and a flare point, the determination of the three-dimensional calibrate of a cornea center, the determination of the three-dimensional of the pupil center, the reconstruction of a visual axis and the final error correction treatment. A camera and two LED light sources are adopted in the gaze tracking system which overcomes the restriction that a head part of a traditional 2 D gaze tracking system need be strictly fixed and the disadvantage that a plurality of cameras or auxiliary devices are required to position the three-dimensional calibrate information of human eyes for 3D gaze tracking, and the invention further provides a gaze tracking method with convenient use, low cost and high accuracy.

A treatment apparatus for operatively correcting myopia or hyperopia in an eye includes a laser device controlled by a control device and that separates the corneal tissue by applying a laser beam. The control device controls the laser device to emit the laser beam into the cornea such that a lenticule-shaped volume is isolated in the cornea. The control device, when controlling the laser device, predefines the lenticule-shaped volume such that the volume has a minimum thickness of between 5 and 50 μm. For myopia correction, the minimum thickness occurs on the edge of the volume, and for hyperopia correction the minimum thickness occurs in the region of the visual axis.

A technique for boresighting an antenna mounted on a moving platform is described. The technique uses a concurrently moving calibration target. Target navigation data and platform navigation data are used to compensate for movement of the target and the platform. The antenna pointing direction is biased in a direction which provides a best signal quality, and the bias used to determine antenna boresight calibration factors. The boresight correction factors can be used for open loop pointing.

A view image rendering module (102) generates an image of a virtual space on the basis of a first viewpoint indicating the viewpoint of a user on the virtual space, and displays the generated image on a view image presentation module (101). A map image rendering module (104) generates a map image indicating a region around the position of the first viewpoint on the virtual space, and displays the generated map image on a map image presentation module (103). The position of the first viewpoint and the visual axis direction are controlled using a viewpoint position•visual axis direction input module (106) which is provided on the display surface of the map image presentation module (103). Furthermore, a virtual object set on the virtual space undergoes manipulation control using a virtual object manipulation input module (107) which is provided on the display surface of the map image presentation module (103).

The invention relates to an aerophotography gyrostabilized platform with three freedom degrees and large load, comprising a platform body, a driving system, an inertia measurement unit, a relative turn angle measuring unit of a ring rack of the platform body, a high-frequency line vibration isolating unit and a platform control system, wherein the inertia measurement unit and the relative turn angle measuring unit of the ring rack of the platform body monitor the information of the angular movement of the platform body caused by the angular movement of the body of an airplane; the platform control system works out a control instruction applied by a relatively determined coordinate system of the platform when being stabilized relative to the driving system at real time according to the monitored information of the angular movement of the platform body by a certain control algorithm; the driving system drives the platform body according to the control instruction to rotate so as to realize the isolation of the angular movement of the body of the airplane; and the high-frequency line vibration isolating unit realizes the isolation of the high-frequency line vibration of the body of the airplane. The aerophotography gyrostabilized platform with three freedom degrees and large load effectively isolates the angular movement and the high-frequency line vibration of the body of the airplane and enhances the stability of a visual axis of an aerial photography camera, and the cost is cheaper.