Abstract: A selection aid for selecting lenses for spectacles on the basis of a plurality of customer-specific criteria contains a first disc and a second disc. The first disc has a selection area with criteria to be selected and selection recommendations and is divided into selection regions of equal size. The second disc is rotatably connected to the first disc about an axis of rotation. The second disc partly conceals the selection area and visually frees an area region of the selection area that corresponds to one of the selection regions in terms of size and shape.

Abstract: A contact lens is placed on a patient's eye during ophthalmic surgery, such as vitreoretinal surgery. The contact lens rests on a cornea of an eye of a patient during the surgery and is supported by a contact lens mounting speculum having multiple degrees of freedom to accommodate small movements of the eye while enabling alignment to an optical axis of the surgical microscope. The contact lens mounting speculum may be used with different patients, speculum blades, contact lenses (direct and indirect), and lens mounting positions.

Abstract: Methods and apparatuses are provided for capturing an image in a portable terminal. An image is received at the portable terminal. An eye region is detected in the image. An eye center of the eye region is determined. It is determined whether a reflection region is detected in the eye region. When the reflection region is detected, a shape of the reflection region is determined, and guide information for preventing the reflection region is output based on the shape of the reflection region.

Abstract: A portable electronic apparatus has a portable electronic device, a lens assembly, a control unit and a display module. The portable electronic device has a shell with a chamber and an opening communicating with the chamber. The lens assembly is mounted in the opening of the shell. The display module is mounted in the chamber of the shell. The control unit is mounted in the portable electronic device to control the display module to project various object images into a user's eyes. The user can exercise the eyes by releasing the eye muscles, tightening the eye muscles, rolling the eyes upwards, downwards, leftwards, rightwards, or rolling the eyes circularly when the user looks at the projected object images. Vision defects, such as myopia and astigmatism, can be relieved.

Abstract: This disclosure relates generally to methods and devices for use in viewing and positioning an eye with a gonio lens system, such as during ocular exams and ocular surgeries. Some embodiments of the gonio lens system can include a gonio lens for viewing one or more tissues and structures of the eye. In addition, the gonio lens system can include one or more positioning features for controlling movement positioning of the eye.

Abstract: This disclosure relates generally to methods and devices for use in viewing and positioning an eye with a gonio lens system, such as during ocular exams and ocular surgeries. Some embodiments of the gonio lens system can include a gonio lens for viewing one or more tissues and structures of the eye. In addition, the gonio lens system can include one or more positioning features for controlling movement positioning of the eye.

Abstract: Various embodiments of a device for performing a gaze field sobriety test are disclosed. The device includes a housing. A light source is affixed in or on the housing. The light source generates light during at least a portion of the gaze field sobriety test. A speaker positioned in or on the housing generates sounds during at least a portion of the gaze field sobriety test. A power source is coupled to the speaker and the light source. An input is positioned on the housing. The input is selectable by a test administrator to initiate an audible sound through the speaker at a predetermined time interval during at least a portion of the gaze field sobriety test. The audible sound provides an indication to the test administrator during the gaze field sobriety test to assist in proper performance of the gaze field sobriety test.

Abstract: Various embodiments of a device for performing a gaze field sobriety test are disclosed. The device includes a housing. A light source is affixed in or on the housing. The light source generates light during at least a portion of the gaze field sobriety test. A speaker positioned in or on the housing generates sounds during at least a portion of the gaze field sobriety test. A power source is coupled to the speaker and the light source. An input is positioned on the housing. The input is selectable by a test administrator to initiate an audible sound through the speaker at a predetermined time interval during at least a portion of the gaze field sobriety test. The audible sound provides an indication to the test administrator during the gaze field sobriety test to assist in proper performance of the gaze field sobriety test.

Abstract: Various embodiments of a device for performing a gaze field sobriety test are disclosed. The device includes a housing. A light source is affixed in or on the housing. The light source generates light during at least a portion of the gaze field sobriety test. A speaker positioned in or on the housing generates sounds during at least a portion of the gaze field sobriety test. A power source is coupled to the speaker and the light source. An input is positioned on the housing. The input is selectable by a test administrator to initiate an audible sound through the speaker at a predetermined time interval during at least a portion of the gaze field sobriety test. The audible sound provides an indication to the test administrator during the gaze field sobriety test to assist in proper performance of the gaze field sobriety test.

Abstract: System and method directed towards providing full and even illumination of a patient's retina through lighting integrated into a handheld fundus lens. By integrating the lighting, the method and system reduces and even eliminate many lens artifacts and reflections. By increasing the accuracy, quality, and field of view afforded during clinical examination of the retina, the method and system will allow practitioners to make more accurate diagnoses and will increase safety during retinal surgical procedures.

Abstract: The present invention is a slit lamp mounted eye imaging, a slit lamp integrated, a handheld, OCT integrated, or attached to a separate chinrest-joystick assembly apparatus and method for producing a wide field and/or magnified views of the posterior or the anterior segments of an eye through an undilated or dilated pupil. The apparatus images sections and focal planes and utilizes an illumination system that uses one or more LEDs, shifting optical elements, flipping masks, and/or aperture stops where the light can be delivered into the optical system on optical axis or off axis from center of optical system and return imaging path from the eye, creating artifacts in different locations on the eye image. Image processing is employed to detect and eliminate artifacts and masks from images. The apparatus can be used in combination with an OCT, microscope and can be disposed in a hand-held housing for hand-held use.

Abstract: Optical coherence tomography (OCT) imaging systems for imaging an eye are provided including a source having an associated source arm path and a reference arm having an associated reference arm path coupled to the source path, the reference arm path having an associated reference arm path length. A sample having an associated sample arm path coupled to the source arm and reference arm paths is provided. A reference arm path length adjustment module is coupled to the reference arm. The reference arm path length adjustment module is configured to automatically adjust the reference arm path length such that the reference arm path length is based on an eye length of the subject. Related methods and computer program products are also provided.

Abstract: In a photometry device, photopic vision luminance Lp is measured by a first luminance measuring unit including a first light filter 4 and a first photoelectric converter 5, and scotopic vision luminance Ls is measured by a second luminance measuring unit including a second light filter 6 and a second photoelectric converter 7. A calculation part 8 calculates mesopic vision luminance Lmes based on a measurement value (photopic vision luminance Lp) of the first luminance measuring unit and a ratio of a measurement value (scotopic vision luminance Ls) of the second luminance measuring unit to the measurement value (photopic vision luminance Lp) of the first luminance measuring unit. Consequently, the photometry device can improve measurement accuracy of the brightness (mesopic vision luminance) in mesopic vision.

Abstract: An ophthalmoscope. Implementations include a handle coupled to a head where the head includes a front section coupled with a diopter wheel and the front section includes a view window. A back section fixedly attached to the front section includes a diopter number viewer, a trigger button, and a digital imaging section. The digital imaging section may include a liquid crystal display (LCD) screen. The trigger button may be adjacent to the handle and may be positioned opposite the front section between the handle and the LCD screen. The back section may include a rounded projection rotatably coupled with a central hole in the diopter wheel extending from a diopter surface substantially parallel with and in close proximity to the diopter wheel. The diopter number viewer may extend from the diopter surface away from the diopter wheel and may include an opening configured to expose a diopter number.

Abstract: Various embodiments of a device for performing a gaze field sobriety test are disclosed. The device includes a housing. A light source is affixed in or on the housing. The light source generates light during at least a portion of the gaze field sobriety test. A speaker positioned in or on the housing generates sounds during at least a portion of the gaze field sobriety test. A power source is coupled to the speaker and the light source. An input is positioned on the housing. The input is selectable by a test administrator to initiate an audible sound through the speaker at a predetermined time interval during at least a portion of the gaze field sobriety test. The audible sound provides an indication to the test administrator during the gaze field sobriety test to assist in proper performance of the gaze field sobriety test.

Abstract: A handheld device for performing an optical medical examination of a patient. The device comprises a handle; an image sensor positioned at an end of the handle; a trigger provided in the handle; an image memory for storing the image data upon activation of the trigger; a roll of print media mounted in the handle; an ink supply within a core of the roll of print media; a media transportation mechanism; a pagewidth print head extending longitudinally within the handle; a guillotine mechanism for severing a printed image from the transported print media; and a print engine controller.

Abstract: A visual field testing apparatus for scanning the visual field of a human eye in great detail, precision, and clarity so as to detect the smallest blind area whereby allowing users the ability of early detection of glaucoma and other eye diseases of visual loss. The apparatus is small and inexpensive so that anyone can afford to purchase it and self-test without assistance so that the user can test frequently at home which further leads to early detection of eye diseases. Because of its great precision and detail in test results, the present invention is especially useful to doctors and researchers.

Abstract: A Pupillometer is disclosed. The Pupillometer has a display, an imaging apparatus that has a pupil finder and a microprocessor, and a memory in communication with the microprocessor. The display is sized to simultaneously display a video of y or more seconds in length of a left pupil and a video of y or more seconds in length of a right pupil. The pupil finder identifies the perimeter of a pupil. The imaging apparatus is capable of recording images of an individual's pupils at a rate of x image frames per second for a period of y or more seconds and playing back said image frames as a video at x image frames per second or at another rate that is faster or slower than x image frames per second.

Abstract: An ophthalmoscope. Implementations include a handle coupled to a head where the head includes a front section coupled with a diopter wheel and the front section includes a view window. A back section fixedly attached to the front section includes a diopter number viewer, a trigger button, and a digital imaging section. The digital imaging section may include a liquid crystal display (LCD) screen. The trigger button may be adjacent to the handle and may be positioned opposite the front section between the handle and the LCD screen. The back section may include a rounded projection rotatably coupled with a central hole in the diopter wheel extending from a diopter surface substantially parallel with and in close proximity to the diopter wheel. The diopter number viewer may extend from the diopter surface away from the diopter wheel and may include an opening configured to expose a diopter number.

Abstract: A lightweight and compact hand-held ocular fundus imaging apparatus is provided wherein alignment can be easily performed while ensuring a working length. An examiner takes hold of a grip by hand and secures a face pad against part of the face of a patient. The examiner performs alignment by tilting a reflecting mirror, and when alignment is complete, an image of the fundus of the patient's eye is taken. An optical system except for the reflecting mirror is disposed on the inside of a main body portion that includes the grip and the face pad, and the reflecting mirror is disposed on the outside of the main body portion. A lever for tilting the reflecting mirror is disposed on the grip. With this type of configuration, the alignment operation can be performed easily and reliably by moving the reflecting mirror while maintaining the apparatus main body in a stable state.

Abstract: An opthalmoscope. Implementations include a handle coupled to a head where the head includes a front section coupled with a diopter wheel and the front section includes a view window. A back section fixedly attached to the front section includes a diopter number viewer, a trigger button, and a digital imaging section. The digital imaging section may include a liquid crystal display (LCD) screen. The trigger button may be adjacent to the handle and may be positioned opposite the front section between the handle and the LCD screen. The back section may include a rounded projection rotatably coupled with a central hole in the diopter wheel extending from a diopter surface substantially parallel with and in close proximity to the diopter wheel. The diopter number viewer may extend from the diopter surface away from the diopter wheel and may include an opening configured to expose a diopter number.

Abstract: A portable, non-invasive binocular scanning apparatus for rapid assessment of neurological function in cases of potential trauma, disease, and/or exposure to chemical treat agents. The scanning apparatus may utilize a combination of light sources for the measurement and assessment of pupillary response, retinal imagery, and/or other ophthalmologic biomarkers. The scanning apparatus can detect and assess a wide range of neurological and physiological conditions by obtaining pertinent measurements from the retina and pupil in real time.

Abstract: An opthalmoscope. Implementations include a handle coupled to a head where the head includes a front section coupled with a diopter wheel and the front section includes a view window. A back section fixedly attached to the front section includes a diopter number viewer, a trigger button, and a digital imaging section. The digital imaging section may include a liquid crystal display (LCD) screen. The trigger button may be adjacent to the handle and may be positioned opposite the front section between the handle and the LCD screen. The back section may include a rounded projection rotatably coupled with a central hole in the diopter wheel extending from a diopter surface substantially parallel with and in close proximity to the diopter wheel. The diopter number viewer may extend from the diopter surface away from the diopter wheel and may include an opening configured to expose a diopter number.

Abstract: An otoscope 800 includes a lens 802 and an eyepiece 801 by which a doctor can examine the external ear cavity of a patient. The otoscope includes a handle 803 within which there is situated a printer to provide an instantaneous permanent record of an image viewed by the doctor. Upon activation of a trigger 817, a permanent graphic image is printed onto a sheet 816 that passes out of the handle 803 via slot 804.

Abstract: A sterile barrier is provided for use with a slit lamp. The slit lamp has a proximal handle and a distal light slit transmitting window. The sterile barrier comprises a flexible tubular membrane having a first end, a second end, and an opening therebetween. The opening may be larger adjacent the first end than a handle of the slit lamp. A resilient band is attached to the first end of the tubular membrane. The first end and resilient band in a resiliently expanded configuration are sufficiently large to receive the handle proximally therethrough. The resilient band in the relaxed configuration will releasably restrain the sterile barrier from moving proximally off the handle.

Abstract: The invention is an eye viewing device having an eyepiece at an observer end thereof and an imaging element at an observation port thereof. Light that is reflected from an imaged eye of a patient is provided to either or both of the eyepiece and the imaging element. A practitioner can view the imaged eye, and can sequentially image the same region of the imaged eye for recording, documentation, and/or analysis.

Abstract: An ophthalmoscopy lens system includes a contact lens and an image forming lens. The contact lens and the image forming lens are in a spaced-apart arrangement such that an open air space exists between the contact lens and the image forming lens and the inner surfaces are exposed.

Abstract: The image-based system is used to observe and document eye responses which can be used to implement the procedures defined in the Standardized Field Sobriety Test as well as the Drug Recognition Expert Program. These eye responses include pupil movement, as well as pupil size and responses, for either one or both eyes simultaneously. The system includes a headset against which the subject places their face. The faceplate has an opening through which illumination devices transmit beams of infrared light to illuminate the subject's eyes. A reflective protractor, having a scale imprinted thereon, is mounted on the headset above the eye opening and facing the test administrator to provide an image of the stimulus target that is used by the test administrator. Two imaging devices are mounted on the headset opposite the eye opening to generate images of the subject's illuminated eyes.

Abstract: A hand held device for examining a patient's retina. In one example, the device generates visible or non-visible illuminating beams having desired spectral content. The illuminating beams are then polarized to generate polarized light beam(s) that are directed towards the patient's retina. At the patient's eye, a portion of the polarized beam is partially reflected by the cornea and travels back to the device, and another portion of the polarized beam enters the eye through the undilated pupil, illuminates the patient's retina, and generates a reflected retinal image (generally de-polarized) which also travels back to the device. The device receives the retinal image and transmits certain portions of the retinal image on through to an image detector (i.e., CCD or CMOS); and the device deflects the received polarized corneal reflections away from the image capture device. Hence, the image capture device receives retinal images but does not receive the polarized corneal reflected light.

Abstract: An ophthalmic device for the examination and detection of opacities in the ocular media comprising a cylindrical housing, a reflecting means located in the housing adapted to reflect light through an illuminating through-hole in the housing, and a viewing port in the housing disposed opposite the illuminating through-hole, the illuminating through-hole, the reflecting means and the viewing port being adapted to define a light path.

Abstract: A pupil measuring device includes a portion that is positioned adjacent to a subject's eye and which includes a plurality of concentric circles on a lens as well as an opaque film that moves to cover the circles. Each circle is marked and the film is aligned with the subject's pupil to be circumjacent thereto. The diameter of the pupil can then be read manually or using electronic circuits with the opaque film being used as the indicator of the measurement.

Abstract: An ophthalmoscope has illuminating optics (10) for projecting a beam of light into an eye under examination and imaging optics (14) for creating an image of said eye for viewing by a user. The imaging optics comprises an objective lens system (16) and an eye piece lens system (20). Two corneal reflex stops (138 and 148) are positioned one on either side of the corneal image formed by the objective lens system. The stops block reflections from the cornea of the eye under examination over a range of distances of the ophthalmoscope from the eye. The use of the two corneal reflex stops results in the precise positioning of the ophthalmoscope relative to the eye under examination not being critical to the blocking of the corneal reflex.

Abstract: The invention relates to a method for carrying out the precise trimming of a lens (1), whereby the lens is held between two clamping plates (2, 3) in a given position and the grinding of the periphery of the lens (1) is controlled along a trajectory, the last programmed part of which corresponds to the form (8) desired for the lens.

Abstract: An ophthalmoscope (800) includes a lens (802) and an eyepiece (801) by which an optometrist, ophthalmologist or general medical practitioner can examine the interior of a patient's eye. The ophthalmoscope includes a handle (803) within which there is situated a printer to provide an instantaneous permanent record of an image as viewed. Upon activation of a trigger (817), a permanent graphic image is printed onto a sheet (816) that passes out of the handle (803) via slot (804).

Abstract: An optometric apparatus for a subjective examination of a visual function of an eye of an examinee includes a pair of right and left lens chamber units, each including, a test window and a rotating disk on which a plurality of optical elements are mounted in a circumferential arrangement to be changeably placed in the test window, the optical elements including a green filter and an aperture.

Abstract: A method for mass manufacturing of eye glasses includes steps of measuring the interpupillary distance of each eye; measuring the refractive error of each eye with a hand-held auto refractor; selecting a lens blank for each eye from among a stock of lenses; cutting a lens blank for each eye; and mounting the cut lens blanks onto a standardized eyeglasses frame.

Abstract: The object of the present invention is to provide a photographing device, iris image input device and iris image input method capable of rapidly and accurately acquiring an iris pattern code of a person to be identified regardless of the height of the person to be identified. In order to achieve this object, with an iris image input device of the present invention, a portable photographing device is connected to a recognition unit and a monitor. The person to be identified that is to photograph their iris uses this iris input device in the following manner. The person to be identified takes the photographing device in one hand, lines up the photographing device with the eye with the iris to be photographed and photographs the iris.

Abstract: A subjective ophthalmic refractor is improved for operator visibility in a darkened examination room by forming a cylinder axis scale of the refractor as a light-transmitting component having opaque scale gradations and installing a polar array of illumination sources to project light through the cylinder axis scale, which preferably includes a translucent material for diffuse illumination. In an alternative embodiment, the cylinder axis scale includes a photoluminescent material to which the scale gradations are applied. The refractor is further improved by installing respective illumination sources near a cylinder power readout and a sphere power readout of the refractor. The disclosure additionally relates to a method for retrofitting an ophthalmic refractor to illuminate the cylinder axis scale, cylinder power readout, and sphere power readout.

Abstract: A compact, handheld imaging apparatus which can be used to capture high-quality iris images for identification of a person. The handheld iris imager is non-invasive and non-contacting and comprises a camera, a cold mirror, a lens, and an illuminator. The imager has sensors and indicators which assist a user in aligning and focusing the device. The imager also automatically captures the image when proper positioning is achieved. A template representative of the iris features is extracted and then compared to a database of previously stored templates to identify the person.

Abstract: Portable hand-held pupillometers for characterizing a subject's pupil which are operated by a user. The hand-held pupillometer comprise optical units for dynamically imaging the subject's pupil, and centering units interfaced and operated by the user for centering the subject's pupil on the optical unit in preparation for imaging the subject's pupil. The hand-held pupillometers taught herein allow a user of the system to accurately and efficiently obtain an image of the subject's pupil which may be particularly useful for the diagnosis of Alzheimer's disease. The centering unit may also be used to display messages or pupil size and dynamic response data to the user in an easily read and useable format.

Abstract: The system of the present invention allows the fundus of an undilated eye to be viewed extremely easily and without the need for the viewer to align a hand held unit with a head mounted unit. The system for viewing the fundus of an undilated eye in accordance with the present invention includes a number of point sources of light that are individually actuable and arranged in a linear array. A lens converts each point of light to a line of light. The point sources of light are sequentially actuated, i.e. turned on and off in sequence, so as to scan the fundus of the undilated eye with lines of light that are directed from the lens to the eye by an optical system. The optical system directs light reflected from the fundus to an image generating apparatus that is responsive to the reflected light to provide an image of the fundus that can be viewed.

Abstract: A portable scanning laser ophthalmoscope with a wide field of view permits a clinician to directly view the interior of the patient's eye without the use of an external monitor or display. The portable scanning laser ophthalmoscope includes a housing that is sufficiently small to be carried and held by a clinician. The housing contains a source of laser light that is scanned by a scanning system for generating a two-dimensional area of illumination. The housing also includes a battery for providing power to the scanning system. An optical system contained in the housing directs illumination from the scanning system to the patient's eye to illuminate the fundus and also intercepts light reflected by the patient's eye to generate a magnified image of the interior of the patient's eye. The optical system also includes an eyepiece lens through which a clinician looks to directly view the magnified image of the interior of the patient's eye.

Abstract: A bar skiascope that has lens slide for displacing a condenser lens along a direction of a light beam also includes a stop slide that can be displaced up to a predetermined maximum position in a displacement path of the lens slide, wherein the condenser lens is located precisely in a position for producing a substantially parallel beam, when the stop slide is in the maximum position, and a stop slide stop element, belonging to the stop slide, and a lens slide stop element, belonging to the lens slide, come into contact with each other.

Abstract: A lens device for examining portions of the human eye comprising inner and outer members each having opposed end portions, the outer member having a viewing lens adjacent one end portion thereof, the inner member being rotatably mountable within the outer member and having at least one mirror associated therewith, the at least one mirror being located adjacent the viewing lens when the inner member is positioned within the outer member, the inner member being rotatably movable relative to the outer member such that the at least one mirror can be selectively positioned relative to the viewing lens so that the appropriate area of the eye can be examined. Preferably, the inner member is rotatable a full 360.degree. while the outer member remains stationary adjacent a patient's eye and, preferably, the inner member includes a plurality of circumferentially spaced mirrors.

Abstract: A portable, binocular direct ophthalmoscope. A frame carrying a binocular optical system is suspended for rotation about a pivot axis from one end of a support beam; an opposite end of the support beam is attached to a handle. A beam splitter block mounted to the frame carries an illumination source for light emission along an illumination axis and into an eye of a subject. Left and right beam splitting mirrors attached to the block are symmetrically and obliquely disposed on opposite sides of the illumination axis. Light reflected back from the subject's eye is split by the beam splitting mirrors into a left-directed beam and a right-directed beam, which are each reflected rearward by laterally spaced apart deflection mirrors through left and right dioptric disk assemblies and thence into the left and right eyes of an observer, respectively.

Abstract: An automated portable keratometer includes a hand held housing and is battery powered. A projection system projects collimated light sources at equal converging angles to an optical axis which extends outside the housing. A camera, including an imaging device, and telocentric objective lens are aligned along the optical axis in the housing. The projection system projects a known pattern of collimated light sources onto a patient's eye. The reflected images of these light sources is captured by the camera and imaging device. Derivation of the distances between certain reflected images can be converted by known algorithms into radii of curvature of the eye. Alignment leveling, and other features can be included with the keratometer. The device can also be used to measure other curved surfaces.

Abstract: A hand-held slit lamp instrument has a substantially elongated handle that houses one or more batteries and that connects to a line filament lamp. A front knob is threaded to the handle so that it is rotatable about the elongated axis of the handle. The front knob has an internal hollow section that houses one or more imaging elements to generate a slit image of the line filament out through an aperture in the front knob and away from the instrument. The rotation of the front knob axially displaces the imaging elements relative to the lamp to control the magnification and distance of the slit image. A rear knob also threads to the handle and rotates about the axis to provide an electrical switch. The rotation of the rear knob displaces the rear knob relative to the handle and between a first "ON" position and a second "OFF" position. A retaining ring, e.g.

Abstract: A field of view collimator for self-monitoring peripheral vision loss. The field of view collimator includes a hand-held housing having a viewing aperture for placement adjacent to the subject's eye. A lens projects an image to the eye. The image, in the form of a circular edge, is formed by an iris diaphragm positioned behind the lens. The angular size of the image is adjustable by opening or closing the iris diaphragm. A diffuser is positioned behind the iris diaphragm to provide an even back-illumination. Indicia markings indicate the measured field of view. The device is particularly suitable for home use by persons with glaucoma.

Abstract: A portable scanning laser ophthalmoscope with a wide field of view permits a clinician to directly view the interior of the patient's eye without the use of an external monitor or display. The portable scanning laser ophthalmoscope includes a housing that is sufficiently small to be carried and held by a clinician. The housing contains a source of laser light that is scanned by a scanning system for generating a two-dimensional area of illumination. The housing also includes a battery for providing power to the scanning system. An optical system contained in the housing directs illumination from the scanning system to the patient's eye to illuminate the fundus and also intercepts light reflected by the patient's eye to generate a magnified image of the interior of the patient's eye. The optical system also includes an eyepiece lens through which a clinician looks to directly view the magnified image of the interior of the patient's eye.

Abstract: Techniques and retinoscopic apparatus for measuring or determining a patient's optical error are disclosed. The techniques include overrefraction and can be performed from a fixed position, avoiding the practitioner's need to move back and forth relative to the patient's eye. Equipment associated with the apparatus is adapted to record the location of the retinoscope slide (relative to its upper or lower position) during the examination to provide information concerning the optical error present in the patient's eye. Other associated equipment can include discs of spherical lenses and devices for limiting relative movement of components of the retinoscopic apparatus. Alternatively, the apparatus may include a scale graduated in suitable units for determining the patient's optical error.