摘要 |
There is presented an improved head-borne binocular indirect ophthalmoscope for viewing the aerial image of the fundus of the eye, having the unique feature that it incorporates within each of its two observing portions a two-lens telescope of low magnifying power which magnifies said aerial image of the fundus. The telescope incorporated into the ophthalmoscope differs from the usual coaxial type in that the optical axis of the high powered objective lens and that of the high powered ocular lens of said telescope are caused to intersect each other at an angle of about 94 DEG at the surface of a laterally positioned oblique front surface mirror, said lenses and said mirror being in a fixed relationship to each other within a transversely movable mounting as a fixed telescope unit such that the reflected secondary focus of the objective lens falls at the primary focus of the ocular lens, said unit being attached to a slide which is transversely movable along ways toward and away from a medially positioned oblique front surface mirror whereby adjustments can be made within the ophthalmoscope to accommodate the interpupillary distance of the observer without affecting the relative position of the elements of said telescope unit.
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