Catalogue Number: 3571
Rodenstock PD (Pupillary Distance) Rule
Sub-Category: PD ruler, pupillometer
Corporation: Rodenstock GmbH
Time Period: 1940 to 1999
Publisher/Manufacturer: Rodenstock GmbH
Description Of Item: Clear flexible plastic rule 205 mm x 25 mm with one triangular end. top edge has an 8 mm x 4 mm cut-out at the triangular end. Bottom edge has two cut-outs 30 mm x 5 mm with a triangular (bridge) cut-out midway between them. A magnifying lens of power +16.50 D and 15 mm diameter is located at the end of the rule. Millimetre gradations, printed in yellow, allow measurement of PD, monocular PD, bridge width and segment height. The word Rodenstock in black and logo in blue are printed adjacent to the magnifying lens.
Historical Significance: A variation on the PD rule adapted to measure monocular PDs and other measurements required for dispensing spectacles.
How Acquired: Donated by Robert Kaye
Date Acquired: 4/3/2014
Location: Archive office. East wall shelves unit 3. Drawer 10