Abstract: A fast position detection system and related method for an ophthalmic instrument utilize stored geometrical relationships determined by multiple regression during instrument calibration to compute X-Y-Z alignment status of the instrument relative to a patient's eye based on local x-y position information from a pair of lateral detectors receiving corneally reflected light from a corresponding pair of lateral light sources. In a preferred embodiment, the lateral detectors are quad-cell detectors. A heads-up display image is preferably provided along an optical axis of the instrument for supplying instructive cues to an operator for moving the instrument to achieve alignment, whereby the operator sees both a macro-image of the patient's eye and the display image. The speed of the position detection system makes it particularly suitable for use in hand-held ophthalmic instruments.

Abstract: An alignment system for an ophthalmic instrument comprises an optical axis along which an operator can directly view the patient's eye and the patient can fixate on a dark fixation target surrounded by a bright background that helps to illuminate the eye for operator viewing. A position detection system utilizing stored geometrical relationships determined by multiple regression during instrument calibration computes X-Y-Z alignment status of the instrument relative to a patient's eye based on local x-y position information from a pair of lateral detectors receiving corneally reflected light from a corresponding pair of lateral light sources. A heads-up display image is provided along an optical axis of the instrument for supplying instructive cues to an operator for moving the instrument to achieve alignment based on signal information from the position detection system, whereby the operator sees both a direct macro-image of the patient's eye and the display image.

Abstract: A hand-held non-contact tonometer comprises a housing having a handle portion for enclosing a rechargeable D.C. power source and an upper head portion for enclosing alignment and tonometric measurement systems of the tonometer. An operator can directly view the patient's eye along an optical axis extending through the head portion of the housing, and an instructional display image is superimposed with the directly viewed image of the eye to guide the operator in X-Y-Z alignment based on data supplied by an afocal position detection system. A transceiver for wireless data exchange and a recharging support stand are also provided.

Abstract: A fast position detection system and related method for an ophthalmic instrument utilize stored geometrical relationships determined by multiple regression during instrument calibration to compute X-Y-Z alignment status of the instrument relative to a patient's eye based on local x-y position information from a pair of lateral detectors receiving corneally reflected light from a corresponding pair of lateral light sources. In a preferred embodiment, the lateral detectors are quad-cell detectors. A heads-up display image is preferably provided along an optical axis of the instrument for supplying instructive cues to an operator for moving the instrument to achieve alignment, whereby the operator sees both a macro-image of the patient's eye and the display image. The speed of the position detection system makes it particularly suitable for use in hand-held ophthalmic instruments.

Abstract: An alignment system for an ophthalmic instrument comprises an optical axis along which an operator can directly view the patient's eye and the patient can fixate on a dark fixation target surrounded by a bright background that helps to illuminate the eye for operator viewing. A position detection system utilizing stored geometrical relationships determined by multiple regression during instrument calibration computes X-Y-Z alignment status of the instrument relative to a patient's eye based on local x-y position information from a pair of lateral detectors receiving corneally reflected light from a corresponding pair of lateral light sources. A heads-up display image is provided along an optical axis of the instrument for supplying instructive cues to an operator for moving the instrument to achieve alignment based on signal information from the position detection system, whereby the operator sees both a direct macro-image of the patient's eye and the display image.

Abstract: A hand-held non-contact tonometer comprises a housing having a handle portion for enclosing a rechargeable D.C. power source and an upper head portion for enclosing alignment and tonometric measurement systems of the tonometer. An operator can directly view the patient's eye along an optical axis extending through the head portion of the housing, and an instructional display image is superimposed with the directly viewed image of the eye to guide the operator in X-Y-Z alignment based on data supplied by an afocal position detection system. A transceiver for wireless data exchange and a recharging support stand are also provided.

Abstract: A lensmeter accessory is disclosed for supporting and positioning a corneal contact lens in a light path of a lensmeter. The accessory comprises a generally planer body with a tapered slot therein having a slot wall defining a recessed groove for receiving and removably holding a contact lens. The accessory may be placed on an adjustable lens platform of a lensmeter to position the contact lens in the lensmeter light path.

Abstract: A polar or vector display provides an operator of an optical instrument with a symbolic instruction regarding the direction and amount of motion required to center an optical element on a chosen path.

Abstract: Optical properties of a lens, including localized defects, are determined by analyzing the refracted image produced by transmitting a beam of light through an aperture and a lens to be tested. The image is reflected onto a light sensitive detecting surface. Information obtained from the light detecting surface is digitized and sent to an Image Processing Unit which calculates the optical properties of the lens. The aperture may consist of a single shaped opening or alternatively a plurality of concentric, annular rings. Correction lenses may be employed, either permanently or selectively, to alter the refracted beam before the beam intersects the detecting surface.