Corneal lenticular incision using a femtosecond laser with smooth scanning trajectory connecting multiple sweeps

    公开(公告)号:US12121476B2

    公开(公告)日:2024-10-22

    申请号:US17658229

    申请日:2022-04-06

    发明人: Wenzhi Gao Hong Fu

    IPC分类号: A61F9/008

    摘要: An ophthalmic laser system and related method for forming a lenticular incision in a corneal lenticule extraction procedure. The lenticular incision is formed by multiple sweeps of a laser scan line along meridians of longitude of the lenticular incision, where the end point of each sweep is connected to the start point of the next sweep by a smooth turning trajectory. The trajectory includes a first circular arc tangentially connected to the first sweep at its end point, a second circular arc tangentially connected to the next sweep at its start point, and a straight line segment tangentially connected to both circular arcs. The smooth trajectory is determined with the given limits of velocity, acceleration and jerk of the XY scanning motors, without using high frequency filters to smooth the trajectory, thereby avoiding unknown changes to the original trajectory and achieving high precision lenticule shapes.

    Multi-use beam sampler in laser beam delivery path of ophthalmic laser system

    公开(公告)号:US11963907B2

    公开(公告)日:2024-04-23

    申请号:US17448175

    申请日:2021-09-20

    摘要: In a laser beam delivery system for an ophthalmic laser system, a single multi-use beam sampler is employed to form three sampled laser beams, including two for redundant laser energy monitoring and one for laser focal point depth measurement. The beam sampler is a transparent plate with preferably parallel front and back surfaces. The front surface reflects a fraction of the incoming beam to form the first sampled beam toward an energy monitoring detector. The back surface reflects another fraction of the beam to form a second sampled beam exiting backwardly from the front surface toward another energy monitoring detector. An objective lens focuses the transmitted beam onto a target, and collects back reflected or scattered light from the target to form a return beam. The back surface of the beam sampler reflects a fraction of the return beam to form the third sampled beam toward a third detector.

    Methods and systems for determining change in eye position between successive eye measurements

    公开(公告)号:US11963722B2

    公开(公告)日:2024-04-23

    申请号:US17229789

    申请日:2021-04-13

    IPC分类号: A61B3/113 A61B3/00 A61B3/10

    摘要: A measurement instrument and method: produce light having a linear shape; direct the light toward an eye via a first lens located one focal length from the light source; provide returned light, having the linear shape, from the eye to a split-prism; split the returned light into first and second linear segments; image the first and second linear segments onto an image sensor; determine a first lateral offset between the first and second linear segments on the image sensor at a first time; determine a second lateral offset between the first and second linear segments on the image sensor at a second time; determine a difference between the first and second lateral offsets; and determine a distance that the eye moved relative to the first lens between the first time and the second time based on the difference between the first and second lateral offsets.