Abstract: This invention concerns a procedure and device for refractometric measurement of the degree of ametropia of a human eye.The device for this invention comprises a light-emitting source combined with a focusing lens, which produces an image of this source on the retina of the eye to be tested, a succession of test lenses which are placed in turn between the eye and the focussing lens, so that the optical axis of the relevant test lens coincides with the optical axis of the eye, and a light-intensity detector placed on this same axis at a fixed distance from the eye, together with means of identifying which test lens causes the detector to emit a signal of minimum intensity.The invention applies to instruments to measure visual acuity, more specifically in handicapped or very young patients.

Abstract: A slim spectacle rim part comprises an integrally lens-holding rim in the form of an open ring and having a pair of side joints provided on the two adjacent ends of the open-ring shaped rim. The molding is of a thermoplastic resin reinforced with short fibers.

Abstract: An optical device comprising, in succession from the object side, light beam control system, a stationary optical element having a reduction-imaging function, and a focusing optical element, the optical device being particularly suitable for use with an eye-fundus camera or the like.

Abstract: A microscope, whose ocular tubes receive light that is reflected by the blind spot or another selected portion in the innermost part of a human eye in response to illumination by a flash unit or a slit lamp, contains an ocular-like casing which replaces one of the oculars and contains a photodiode located in the respective image plane and generating signals denoting the intensity of light in the respective image plane. Such signals are transmitted to one input of a dividing circuit which further receives signals denoting the intensity of light which is emitted by the light source of the flash unit or slit lamp. The signal at the output of the dividing circuit is displaced and/or recorded and is indicative of reflectivity of the selected portion. The other ocular tube of the microscope contains a customary ocular with a marker located in the respective image plane.

Abstract: Disclosed is a light splitter in which a number of minute inclined surfaces inclined with respect to the surface of a parallel planar glass is formed. At least part of a light beam having entered the light splitter travels while being totally reflected by said surface and said inclined surfaces and the remainder of the light beam travels without being totally reflected by said inclined surfaces.

Abstract: An optical element includes an ogival reflective surface which diverges an incident radiant energy beam substantially uniformly into a 2.pi. solid angle. The precise shape of the reflective surface is defined mathematically in relation to the desired solid angle of divergence and energy distribution of the incident beam. To facilitate mounting and alignment of the reflective surface in an optical system, it is formed internally of a body of optically transmissive material. The external surface of the transmissive body is shaped so as to provide normal incidence for rays reflected from the reflective surface. The element may be used as a beam diverger, or alternatively in reverse, to converge and collimate radiation.

Abstract: A pair of clip-on cuffs for attachment onto the ear-engaging portion of the temples of a pair of eyeglasses. The cuffs are preferably made of translucent acrylic material and are C-shaped in cross-section to fit over and firmly grip the ear-engaging portion of each temple. The cuffs cover about an inch of the temple's length and have a thickness of about 1/32nd of an inch. The outer surface of each cuff includes a series of smoothly raised areas such as parallel ridges, cross-hatched ridges or hemispherical protuberances to increase the traction between the eyeglasses and the skin of the wearer.

Abstract: Apparatus and method for use in ocular surgery to enable the surgeon to determine the degree of self correcting astigmatism to apply to the eye during the suturing procedure. The apparatus comprises an ocular microscope provided with a device for directing a ring of light onto the anterior surface of the cornea of the eye such that the cornea will reflect the ring for viewing in the eyepiece of the microscope. The eyepiece is provided with means for determining the shape of the reflected ring and hence the degree of astigmatism applied to the cornea by the surgeon. In particular this means may be in form of a comparison ring which may be viewed in the same field of view as the reflected ring and being adjustable by the surgeon to provide a series of comparison rings for comparison with the reflected ring and corresponding to successive degrees of corneal astigmatism.

Abstract: A technique is disclosed for monitoring the eye movements of a subject with apparatus that is removably attachable to the subject's own eyeglass frame. The apparatus includes a light source to bounce light off the subject's eye and a detector to sense the reflected light. Both are adjustably mounted on a support. The support includes several interlinked parts which are readily adjustable to fit the subject's eyeglass frame.

Abstract: An adjustable eyewear retainer of fabric-covered elastic form material, for holding eyeglasses and the like securely in place on a wearer's head, providing padding for the bow portions of the eyeglasses which fit behind the wearer's ears. A pair of tubular members, which fit over the downwardly curved bows of a pair of glasses, are attached to the respective forward ends of a pair of elastic straps at an acute angle. Mating pieces of hook-and-loop fastening material are provided on the rear ends of the straps to provide for adjustable fit and easy removal of the glasses as desired. Parts of the tubular members are lined with fabric, while a short rear end part of each tubular member may have a rubber-like inner surface to provide increased grip on the bows of a pair of glasses. Adhesive construction is used.

Abstract: Apparatus for projecting at infinity an image of an object displayed on a convex surface, such as a CRT or rear projection screen. Such apparatus comprises a pair of beam-splitters, preferably cylindrical in shape and arranged such that their respective axes of curvature are perpendicular to one another. Each beam-splitter has an optical power which compliments that of the other, whereby such elements share the image-forming function.

Abstract: A zoom lens having at least three components, or, from front to rear, a first component of positive power, a second component of negative power and a third component with the air separations between the successive two of said three components being varied to effect zooming, whereby said first component is constructed with, from front to rear, a bi-convex first lens, a second lens of negative power and a third lens of positive power.

Abstract: Optical elements shaped in accordance with preferred analytic functions which permit the elements to be relatively rotated about one or more pivots decentered with respect to an optical axis to simulate the dioptric action of a well corrected rotational lens element of variable power that can be used to maintain focal setting over a large range of object distances. The optical elements can be used in pairs, singly with mirror images of themselves, or they can be incorporated in more elaborate systems to provide focusing action.

Abstract: An optical viewing system for use by bicycle riders and the like to increase the field of vision thereof includes headgear for supporting the system on the head of the user and an optical viewing accessory attached to the headgear. The optical viewing accessory has a pair of prisms thereon mounted for pivotal movement between retracted and extended positions. In their retracted positions, the prisms do not interfere with the direct line of sight of the user. However, in their extended positions, the prisms intersect the direct line of sight of the user and the internal reflection and refraction of the prisms allow the user to view objects located at positions at an angle, approximately ninety degrees, from the direct line of sight. The pivotal movement of the optical viewing accessory is activated under the influence of gravity as the head of the user is manipulated alternatively between the erect and prone positions.

Abstract: A photographic lens system having a field angle of 70.degree. or wider and designed for use with compact cameras having a relative aperture of F/3.5 comprising a first positive meniscus lens component having a convex surface on the object side, a second positive meniscus lens component having a convex surface on the object side, a third negative meniscus lens component having a convex surface on the object side, a fourth lens component having positive refractive power, and a fifth lens component comprising a negative lens element and having positive refractive power as a whole.

Abstract: An ophthalmic instrument support having a flat floor-supported base and a cabinet extends upward from one end of the base, a post projects upward from the cabinet and the upper end of the post pivotally engages one end of a horizontal frame upon which a table is mounted for limited horizontal movement to permit a pair of spaced instruments thereon selectively to be brought into alignment with the eyes of a patient when seated in a vertically adjustable chair with the patient's lap extending beneath the horizontal frame. The post is adjustable vertically a limited amount to dispose the table and instruments thereon at a desired vertical position according to a doctor's eyes when the doctor is seated upon another chair opposite a patient.

Abstract: An ophthalmoscope having two lens discs one of which has three different lenses and the other of which has twenty-three different lenses. There is a viewing path through the instrument and, in use, one lens in each disc will always be in registry with the viewing passage. The two lens discs in combination provide sixty-nine different diopters ranging from -30 to +38 diopters. The lens discs have a common axis of rotation and are spaced apart so as to permit a cam plate to be positioned between the discs in close proximity to each. The cam plate is operable to provide an automatic lens shifting mechanism for the pair of lens discs.

Abstract: A method and apparatus is shown for receiving optical rays with a maximum angle of sensitivity so that a single detector can monitor a wide, spherical angle. This method is used with infrared detectors which would be mounted on a wall to switch the lamps of a room on and off as soon as a person enters the room.

Abstract: An objective to be used with a single-objective type binocular stereomicroscope which comprises an objective for forming an afocal image, and two observation optical systems for observing the afocal image by the right and left eyes, the objective being arranged to fulfill the condition shown below so as to thereby prevent the error in the sense of depth and distance from occurring.

Abstract: In an optical system with an optical axis in which an image is to be focused at an image plane, an improved chopper which can be driven at a high rate for obtaining dither about the focal point in the system includes first and second chopper blades, each having at least one notch in their periphery, the chopper blades mounted to a common shaft adapted for rotation, parallel to each other and essentially perpendicular to the optical axis and on opposite side of the image plane, the outputs of one of the blades will representing an ahead of focus edge response and the other of said blades a behind focus edge response which can be sensed and processed to carry out correction of the optical system.