A combined binocular ophthalmoscope and headlamp.

Abstract

THE Hallpike Headlamp, which can be worn comfortably with operating spectacles, provides even illumination of the operative field, and the Fison Binocular Indirect Ophthalmoscope is of value in the examination of retinal detachments. The two instrument heads are now available with an easily interchangeable mounting, on a modified head harness of the type supplied with the Hallpike instrument, securing comfort in prolonged wear in theatre.A'S The Figure shows how the two instruments are fitted with similar screws to be attached by the captive knurled nut to the bar of the headpiece. Short leads come from the lamp of each instrument to plug into the socket seen on the right of the mounting plate.The instrument is stored with the ophthalmoscope head in place, but is rapidly converted to a headlamp when required.The headlamp employs a double-lens system, comprising condensing and projecting lenses, but the ophthalmoscope has a singlelens system, providing a nearly collimated beam FiGuRE-Ophthalmoscope and headlamp grouped with harness, to show the with an image of the mounting bar with captive knurled knob and the mounting screws on the back ifian atin t of the instruments, filament at infinity. The different optical principles and applications of the two instruments admitted no easy compromise in single form, and this combination set was designed as the simplest solution to the problem.