Abstract: Systems for performing combined phoropter and refractive measurements to ascertain the aberrations present in the eye of a subject. The systems use a pair of phoropter wheel assemblies, one for each eye, each assembly comprising a number of lens wheels incorporating the series of lenses and wedges required to compensate for a range of refractive vision aberrations. The vision of each eye is corrected by a combination of a subjective phoropter measurement, iteratively performed with an objective wavefront analysis measurement to determine the residual aberrations existing after the initial phoropter correction. The system is able to automatically align the axes of each wavefront analyzer with is corresponding eye, by means of centering the pupil image in the wavefront analyzer camera, and to determine the pupil distance. By changing the focusing point on the wavefront analyzer of the light reflected from the eye, the corneal profile can be measured.

Abstract: A system for holding and aligning spectacles such that mapping measurements of the optical properties of a lens can be performed with the lens held such that its optical axis is parallel to the incident measurement beam. This may be implemented using three points which define a plane with which a surface of the lens can be aligned. The frame gripper is constructed such that the lens to be measured is free to rotate in space around any axis until clamped by the three alignment pin support arrangement, with the exception of rotation around the optical axis of the lens. This freedom of rotation allows the lens to be positioned on the alignment pin support automatically without the need for operator intervention. The spectacle frame is clamped using a spring loaded caliper device, configured to sequentially align the mechanical center of each lens with the measuring beam.

Abstract: Systems for performing sequential multiple function ophthalmic measurements using separate measurement instruments, by mechanical switching between the instruments. In prior art systems, the separate measurement instruments are stacked, and transfer between them is performed by means of a linear mechanical motion stage. The separate measurement instruments of the present application are mounted on a base which is rotatably pivoted around a joint at a location remote from the optical entry apertures of the instruments. The entrance apertures of the measurement instruments then traverse the eye being measured sequentially. A rotational motion around the pivoted joint is thus transformed into a linear motion at the eye of the subject, without the need for a linear motion stage. A Scheimpflug camera corneal thickness measurement is also described, in which the measurement head is tilted during the corneal scan such that the illuminating slit beam always impinges on the cornea normally.

Abstract: A wavefront measurement system, for measurement of aberrations in the eye, and for measurement of the topography of the cornea of the eye. The system differs from previously available systems in that the wavefront measurement of the eye's aberrations can be performed as a function of eye accommodation. Furthermore, methods for reducing corneal reflection are described. Additionally, the use of a very short focal length Hartman Shack lenslet array enables a very wide range of low order aberrations, up to ±25 diopters, to be measured without any refocusing or motion of the system. Also, methods are described for enabling the presence of defects within the eye to be determined using the aberration measurement system. Another embodiment captures the pupil centering position without any projected illumination pattern being used, so that a subsequent accurate centering and focusing procedure can commence at the initially captured position, thus reducing measurement time.

Abstract: Systems for performing combined phoropter and refractive measurements to ascertain the aberrations present in the eye of a subject. The systems use a pair of phoropter wheel assemblies, one for each eye, each assembly comprising a number of lens wheels incorporating the series of lenses and wedges required to compensate for a range of refractive vision aberrations. The vision of each eye is corrected by a combination of a subjective phoropter measurement, iteratively performed with an objective wavefront analysis measurement to determine the residual aberrations existing after the initial phoropter correction. The system is able to automatically align the axes of each wavefront analyzer with is corresponding eye, by means of centering the pupil image in the wavefront analyzer camera, and to determine the pupil distance. By changing the focusing point on the wavefront analyzer of the light refleeted from the eye, the corneal profile can be measured.

Abstract: A system for holding and aligning spectacles such that mapping measurements of the optical properties of a lens can be performed with the lens held such that its optical axis is parallel to the incident measurement beam. This may be implemented using three points which define a plane with which a surface of the lens can be aligned. The frame gripper is constructed such that the lens to be measured is free to rotate in space around any axis until clamped by the three alignment pin support arrangement, with the exception of rotation around the optical axis of the lens. This freedom of rotation allows the lens to be positioned on the alignment pin support automatically without the need for operator intervention. The spectacle frame is clamped using a spring loaded caliper device, configured to sequentially align the mechanical center of each lens with the measuring beam.

Abstract: Systems for performing sequential multiple function ophthalmic measurements using separate measurement instruments, by mechanical switching between the instruments. In prior art systems, the separate measurement instruments are stacked, and transfer between them is performed by means of a linear mechanical motion stage. The separate measurement instruments of the present application are mounted on a base which is rotatably pivoted around a joint at a location remote from the optical entry apertures of the instruments. The entrance apertures of the measurement instruments then traverse the eye being measured sequentially. A rotational motion around the pivoted joint is thus transformed into a linear motion at the eye of the subject, without the need for a linear motion stage. A Scheimpflug camera corneal thickness measurement is also described, in which the measurement head is tilted during the corneal scan such that the illuminating slit beam always impinges on the cornea normally.

Abstract: A wavefront measurement system, for measurement of aberrations in the eye, and for measurement of the topography of the cornea of the eye. The system differs from previously available systems in that the wavefront measurement of the eye's aberrations can be performed as a function of eye accommodation. Furthermore, methods for reducing corneal reflection are described. Additionally, the use of a very short focal length Hartman Shack lenslet array enables a very wide range of low order aberrations, up to ±25 diopters, to be measured without any refocusing or motion of the system. Also, methods are described for enabling the presence of defects within the eye to be determined using the aberration measurement system. Another embodiment captures the pupil centering position without any projected illumination pattern being used, so that a subsequent accurate centering and focusing procedure can commence at the initially captured position, thus reducing measurement time.