Abstract: An optical probe assembly for detecting the position of an object surface, especially the position of a three-dimensional, curved surface such as a surface in a contact lens or the cornea of the eye, is disclosed herein. This assembly and its method of operation use a beam of light which is focused to a point and an arrangement for automatically causing this point to move or scan in a predetermined way relative to the object surface including reciprocally through the surface for causing light to be reflected back from the latter. During this scanning period, when the beam point is coincident with the object surface, the amount of light which is reflected back along the path of the incident beam is maximized and automatically detected. At the same time, the position of the beam point relative to a known reference is automatically monitored and in combination with the detected light is used for determining the position of the object surface relative to this reference.

Abstract: A process and apparatus for the calibration of an optical instrument. An optical instrument--such as a lens meter or ophthalmometer--is provided with a light source, a light detector, and an optical train of assembled optical elements therebetween. A suspect optical element to be measured is placed within the optical train at a measuring interval to deflect light passing along the optical train. An occulting moving boundary locus having at least two boundaries of differing shape, and a dedicated computer may be used to measure beam deflection. The dedicated computer also makes use of stored computer constants to transform raw measurements into the desired optical properties of the suspect optical element. The optical train of the instrument has its assembled optical elements randomly placed to production tolerances; precision registration of the optical elements to traditional close optical tolerances is omitted.

Abstract: A unitary light source is imaged through a prism array to generate a plurality of preferably four apparent light sources forming a point of origin for a discrete lens sampling light path. From each apparent light source, each discrete sampling path diverges to a relay lens system. This relay lens system relays and registers to a lens sampling interval discrete images of each apparent light source. The images may be registered to a correspondingly apertured lens sampling diaphragm against which suspect optics are placed for measurement. A moving boundary locus sweeps the light between each apparent source and the sampling interval with paired boundaries of differing slopes which produce non-ambiguous points of intersection with respect to time. After passage through the suspect optics at the sampling interval, light is passed to a photodetector having an overlying set of apertures, each aperture corresponding to one of the four apparent light sources.

Abstract: An automated readout for a lens meter is disclosed in combination with a light beam deflecting type of lens meter such as that of a Hartman test. In such a light beam deflecting type of lens meter, a light source having one or more beams is passed through a suspect optical system and deflected by the suspect optical system to a deviated path. Measurement of the deviated path within a preselected area of excursion is typically equated to various powers of the suspect optical system in sphere, cylinder, cylinder axis, and prism. The invention provides for a means of measurement of deviated paths and includes a moving boundary locus with edges of distinctly different shape placed to intercept and occult said deflected beam in a known plane within the area of excursion at a distance from the suspect optical system. The moving boundary locus is typically arranged for movement along a predetermined path at a velocity within the known plane.

Abstract: Apparatus for measuring the refractive properties of a sphero-cylindrical lens system of the type utilizing an incident light beam scanned in at a predetermined radius about the central axis of the lens system to provide a refracted beam. A generally opaque mask having an annular transparent portion is positioned in the path of the refracted beam, to eliminate errors caused by deviations in radial height from the scanning radius of the refracted beam as it exits the lens system due to refraction within the interior of the optical system. A position-sensitive photodetector generates a signal indicative of the instantaneous position in a given plane due to refraction of the portions of the light beam passing through the mask. The photodetector output signal is then processed to provide an indication of the refractive properties. Various embodiments of the mask are also disclosed. Also permutations of the above including pinhole aperture, input light and other detection means is discussed.

Abstract: Method and apparatus for the precision blocking of lens blanks using a holder to de-center the blank and fix its optical axis. The holder is then used to position the blank with respect to a blocker by which an alloy hub or "block" is removably affixed to the blank so that it can be properly gripped for conversion into a finished lens product.

Abstract: A lens meter for analyzing suspect lenses in terms of sphere, cylinder and axis by optical beam deflection and without relatively moving optical parts is disclosed. A light source emanating a substantially collimated beam of light from an entrant aperture into a retroreflecting mechanism includes two important properties. The first property is that an image of the entrant aperture is displayed from and reimaged across the optical axis of the retroreflector to a conjugate location at a real image exit aperture, this aperture being provided with a coincident optical stop. Secondly, in the absence of a test lens in the light path, light entrant to the retroreflector through the entrant aperture along a first path departs the real image of the exist aperture along a second path with a known angularity to the first path.

Abstract: Apparatus for measuring the refractive powers of a lens and displaying the measured powers in so-called prescription form. A focimeter is equipped with means for generating electrical signals indicative of the net refractive powers of the lens, which signals are extended to novel electronic logic and control means for ultimately reading out and/or displaying the lens powers in a prescription form having "sphere" and "cylinder" components of power. Selectively activable control means determine whether the prescription is displayed in so-called "+ cylinder" notation or "- cylinder" notation. Additional means are provided for indicating which of two possible axis angles is correctly associated with the particular displayed component of cylinder power.

Abstract: A device is provided for use with a lensometer which will adjustably hold a ground lens as it is moved until its optical center coincides with the line of sight of the lensometer. The device is provided with two spaced apart, fixed markers and a line passing therethrough will indicate a horizontal line passing through the optical center of the lenses when they are fitted into the frames of the eye spectacle. The device is also provided with a movable marker, movable precise amounts in accordance with the prescription of an individual patient for a particular spectacle frame to indicate the geometric center of that lens when mounted in that spectacle frame and for that particular patient.

Abstract: Optical test apparatus and method for testing various parameters of a lens system such as a T.V. lens system. A single apparatus may be used for testing the modulation transfer function, glare, spectral transmission, relative field illuminance, transverse color, T stop, and back focal distance.The apparatus comprises a pin hole light source and an analyzer means in which the lens may be mounted including a set of screens carrying varying patterns for measuring different parameters. The light transmitted through the screens is measured by a light detector means and the output signal is analyzed to provide a measurement of the parameters.

Abstract: Apparatus for measuring the refractive properties of an optical system of the type utilizing a light beam scanned in a circle or predetermined radius about the central axis of the optical system to provide a refracted beam. A generally opaque mask having specially configured annular transparent portions positioned in the path of the refracted beam to eliminate errors caused by deviations in radial height from the scanning radius of the refracted beam as it exits the optical system due to refraction within the interior of the optical system. A position-sensitive photodetector generates a signal indicative of the instantaneous position in a given plane due to refraction of the portion of the light beam passing through the mask. The photodetector output signal is then processed to provide an indication of the refractive properties.

Abstract: In combination with a lens meter for measuring along a single optical path the power of suspect optics, an apparatus for positioning nose bridge mounted spectacles is disclosed. At least one nose locator piece simulating the shape and location of the human nose is mounted for sliding movement on a bar. A bar locks vertical lens movement on the base of the lens frame at the bottom of the lenses to establish the elevation of the visual center on each lens for each eye. The transverse spacing of the nose locator piece locates the remaining coordinate of the visual center of the suspect lens. The nose locator piece, when registered to the spectacles at the nose bridge, is read through an attached and typically magnified scale to indicate nose bridge to visual center distance. By using paired nose locator pieces and paired scales, rapid measurement of nose frame mounted spectacles can occur at the spaced visual centers for the right and left eye lens to a lens meter having a monocular light path.

Abstract: Method and apparatus for the precision blocking of lens blanks using a holder to de-center the blank and fix its optical axis. The holder is then used to position the blank with respect to a blocker by which an alloy hub or "block" is removably affixed to the blank so that it can be properly gripped for conversion into a finished lens product.

Abstract: A lens meter is disclosed in which continuously variable spherical and astigmatic corrective optics are manipulated to measure the prescription of a suspect optical system. A target including a straight line is focused for maximum clarity, the target being arbitrarily aligned without respect to the axis of the suspect optical system. Continuously variable spherical and first astigmatic optics are juxtaposed to the suspect optics and the image of the target projected through both the suspect optics and the continuously variable optics. Spherical and first astigmatic corrections along at least one axis diagonal to the line target is made until maximum sharpness of a projected image of the line results. A first component of astigmatic correction results. A second target, again consisting of a straight line, is introduced; this target is angularly inclined with respect to the first target preferably at 45.degree..

Abstract: A lens meter includes a target, a collimator lens system for forming an image of the target, a member having a reflecting surface facing the collimator lens system, and an indicating plate disposed at the focal point of the collimator lens system, and at a side opposite to the reflecting member relative to collimator lens system. The reflecting member is placed on the optical axis of the collimator lens system at a side opposite to the target relative to the collimator lens system. The reflecting member is movable along the optical axis and the target is placed at the focal point of the collimator lens system. The lens meter may further include a beam splitter for dividing the optical axes into two optical axes. In this case, the target is placed on one of the divided axes and the indicating member is placedon the other divided axis. Further improvement may be attained by providing in a suitable arrangement two polarizing plates and a quarter-wave plate.

Abstract: A device for automatically measuring the spherical power, cylindrical axis and power and prism of an ophthalmic lense, with each determined independently of each other without a servo system. At least two LEDs act as point-sources of light, as Scheiner apertures. The light from the LEDs pass through an objective lense, thence through a selectively translatable aperture target, and then pass through a collimating lense. The LED rays then pass through the lens under study, and the target images are focused by a telescope objective lens onto a light sensitive detector. The detector which is selectively rotatable in concert with the LEDs is partitioned into Cartesian quadrants. Rotation of the detector and LEDs until the target images fall on the major detector axis discloses the axis of the cylinder of the lens being measured independent of lens power. Translation of the target until the target images maximally coincide reveals the power of the lens in its principal meridian.