Abstract: An interpupillary distance measuring device comprises a box with a front panel whose position corresponds to an eyeglass frame. The device has a main axis perpendicular to the front panel and equidistant from the eyes of the subject. A horizon plane perpendicular to the plane of the face passes through the main axis and the eyes of the subject. In the box are a master lens and a point light source at the focus of the lens and on the main optical axis. The point source creates at the center of the eyes of the subject corneal reflections, virtual images of which are formed by the lens. These virtual images form real objects for an objective lens which forms a pair of real images on a measurement scale formed by one or more linear arrays of photosensitive charge transfer devices. The device scans sequentially to identify the elements of the arrays at which the images are formed by means of the rank of those elements.

Abstract: The present invention relates to a device for detecting and/or measuring visual deficiencies in which an image observable by a patient presents several series of test signs, each corresponding with one of the various levels of visual acuity, wherein each sign corresponding to a level of visual acuity is associated to a reference sign corresponding to a lower level of visual acuity and wherein frame 1 contains signs corresponding to a visual acuity of 1/10, another frame 2 to 2/10 and following frames correspond to visual acuities ranging by steps of 2/10 respectively from the value 4/10 to the value 10/10.

Abstract: The present invention relates to an apparatus for eye sight examination, allowing to test both of the patient's eyes, especially to detect his common failures and vision defects, for far and close vision, and eventually intermediary distance vision.The test-image are borne by at least one ribbon or band mounted in a block of two winding spools, housed in a body forming an easily removable tape box of an adequate support of body of the apparatus.The invention applies to the automatic or semi-automatic detection of visual defects of a patient.

Abstract: A device (1) for measuring the ocular parameters of a subject is of conventional optical design, with a front panel (10), a convergent lens (11), an aiming hole (12) at the focus of the lens (11), and a light source (13) whose image in a semi-reflecting mirror (14) appears as a point at infinity. Liquid crystal matrixes are disposed in windows (15, 16, 17, 18) and controlled by a logic unit (20) connected to a control keyboard (21) and a display (22). Looking through the hole (12), the operator uses the keyboard (21) to send address signals from the logic unit (20) either to the columns of the top matrixes (15, 16) or to the lines of the top and bottom matrixes (15, 16, 17, 18). According to the operating modes selected, vertical lines appear in the top windows (15, 16) to measure the interpupillary distance or horizontal lines appear in all four windows for centering the lenses in the frame.

Abstract: The invention concerns a process and device for the positioning of an optical measuring instrument and a spectacle frame in relation to each other. The practitioner, operating from a position roughly determined by the point at which the two optical paths converge adjusts the relative position of the spectacle frame and measuring instrument so that the reflection of the side edge of the frame in a semi-transparent mirror located on each side of the device appears directly over the actual image of an alignment mark behind the mirror. This convergence indicates that the frame is in the correct position in relation to the measuring instrument.