This unit consists of a light, easily maneuvered, illuminated monocular eyeglass loupe which can be made to fit firmly on any size or shape of wearing glass. The lighting unit, which is part of the instrument, serves to illuminate the field of inspection adequately.
The optical principle of this unit is similar to the jeweler's loupe and to a unit previously described by me.1 In brief, its construction is as follows:
1. A magnifying biconvex (plus) lens of selective strength mounted in suitable cylindrical bed, threaded on the outside to hold an easily removable adapter ring. Lenses of desired strength may be used to meet the requirements of the individual practitioner. For the present, I am depending on two strengths of lenses, + 17 D. and + 10 D. The lens housing proper is set at a convenient distance of about 1 inch from the wearer's eyeglass to increase the working
KRIMSKY E. AN ILLUMINATED MONOCULAR EYEGLASS LOUPE. AMA Arch Ophthalmol. 1951;46(3):339-340. doi:10.1001/archopht.1951.01700020348011