Echelon Soft Bifocal Contact Lens Trial Set
 Catalogue Number: 2531 Echelon Soft Bifocal Contact Lens Trial Set Category: Spectacles and lenses Sub-Category: Contact lenses and accessories Corporation: Allergan Optical Inc. Year Of Publication/Manufacture: 1990 Time Period: 1940 to 1999 Place Of Publication/Manufacture: Woodbury, NY, USA Publisher/Manufacturer: Allergan Optical Inc. Description Of Item: Hinged plastic box, 245 x 160 x 40 mm, with a blue base and clear top with the words Allergan Hydron printed in blue in the bottom left hand corner. The base has compartments for 24 lens vials and contains 16 trial lenses with expiry dates from 10/95 to 4/96. Four lenses are +/- 0.75, four are +/-2.75 with +1.50 Add, four are +/-0.75, three are +/-2.75 and one is +3.00 with +2.00 Add. Historical Significance: Allergan Hydron introduced the Echelon diffractive bifocal soft lens in 1990. It was a soft version of the Diffrax rigid lens. The lens was cast moulded and had a series of concentric rings < 3 microns in depth. All were 8.7 mm base curve, 13.8mm diameter and 38% water content. Power range was +4.00 to -6.00D and adds of +1.50 and +2.00 How Acquired: Donated by Colin Bates Date Acquired: 16/01/2013 Condition: Good Location: Archive room. West wall. Unit 6 Drawer 5 |