Rigidity of Construction
Illustration on following page ([Fig. 11a]) shows the reinforced double bearing arms which hold the Ski-optometer lens batteries at two points. This eliminates possibility of the instrument getting out of alignment, and prevents wabbling or loose working parts.
The broad horizontal slides shown in the cut, move in and out independently so that the pupillary distance is obtained for each eye separately by turning the pinioned handle on either side of the instrument. The scale denotes in millimeters the P.D. from the median line of the nose outward, the total of both scales being the patient’s pupillary distance.
[Fig. 11a] also serves to show the staunch construction of the base of the Ski-optometer.
Fig. 11a—Showing staunch construction of Ski-optometer base.