At the 1953 Session of the American Academy of Ophthalmology and Otolaryngology Conover and Spaeth1 described an instrument which was devised to obtain more accuracy in central field examinations in less time than was usually required for this examination with other tangent screens. A concealed magnet was used to move the test object. The magnet moves through an open calibrated channel.
Harrington and Flocks2 described the multiple-pattern visual field screener in 1954. They describe it as being an instrument for rapid qualitative examination which uses patterns printed in white fluorescent sulfide ink on 14 by 18 in. white cards; the fixation point is a 5 mm. black dot.
In an article summarizing recent instruments for perimetry, I3 suggested the possibility of combining the two instruments to eliminate a piece of apparatus in the office.
The Harrington-Flocks screener was prepared by having a nonferrous top made which was
ZUGSMITH GS. A Combination of a Magnetic Tangent Screen with the Harrington Multiple-Pattern Field Screener. AMA Arch Ophthalmol. 1957;58(2):256. doi:10.1001/archopht.1957.00940010268014