Abstract: A binocular head mounted display system is shown utilizing an aspheric lens in each of the user's right-eye and left-eye optical paths. The aspheric lens is formed with a number of concentric zones for controlling the distance at which an image of displayed information is projected from the user and to minimize distortions across the virtual image. The distance between each lens and its respective display is independently variable. Further, the distance between the optical system as a whole and the user's eyes is variable.

Abstract: A head mounted display system is shown having a single optical element. The single optical element has three optical surfaces. An entrance surface receives a video image directly from a display. A reflective surface reflects the video image from the entrance surface to an exit surface wherein the user views the video image directly through the exit surface. The three optical surfaces are shaped to generate a virtual image that is magnified, appears at a distance from the user and substantially free from distortion, astigmatism and chromatic aberrations. The optical element is adjustably mounted on a frame of the head up display system to accommodate users with different interpupillary distances and to vary the apparent distance between the user and virtual image.

Abstract: A lens allows a wide field of view of the interior of a patient's eye to be observed without requiring the eye to be dilated. The lens is nonsymmetric and formed of an optically transparent material having two nonspherical surfaces. The surface of the lens facing the patient's eye has a curvature sufficient to bend the image forming rays emanating from the undilated eye towards a second surface which has a curvature sufficient to form the rays into a planar, real, inverted image of the fundus with a field of view of greater than 60.degree. and a ratio of the effective focal length of the lens to the lens diameter that is less than 0.5.

Abstract: An ophthalmic lens having two elements, a contact lens and an entry lens. The lens produces a magnified aerial image of the fundus of the eye, and can also be used for laser delivery to the fundus. The lens is particularly useful because it provides high magnification and detail of the fundus as well as excellent steroscopic field.

Abstract: An ophthalmic lens which has three elements, a contact lens, a center lens, and an entry lens. The lens produces a magnified aerial image of the fundus of the eye. The lens is particularly useful because it provides high magnification and detail of the fundus as well as good stereoscopic field.

Abstract: An ophthalmic lens which has three elements, a contact lens, a center lens, and an entry lens. The lens produces a wide field, aerial image of the fundus of the eye. The lens is particularly useful because it provides high resolution of the peripheral retina, and causes little or no distortion of the laser beam used for peripheral fundus laser treatment.

Abstract: An attachment for a slit lamp that permits the operator to view the superimposition of an image of a patient's eye and a second image that may comprise a fluorescein angiogram or other photographic image of the patient's eye, or an image formed by a CRT or other display system. The slit lamp includes an objective for forming the first image directed along a first optical path, an eyepiece, being attachable to the objective such that the eyepiece is positioned along the first optical path. The attachment includes a body, a beamsplitter, and an image forming system. The body includes an attachment for attaching the body between the objective and viewing means, and also includes a passage through which the first image can pass along the first optical path to the eyepiece. The beamsplitter is mounted in the body, and positioned in the first optical path. The image forming system projects the second image onto the beamsplitter, such that a portion of the second image is reflected along the first optical path.

Abstract: An ophthalmic lens utilized for observing the fundus of an eye using through the lens illumination and for delivering a focused laser beam to the fundus includes a contact lens and an aspheric entry lens. In combination, the lenses provide an aerial image of the fundus anterior to the entry lens.