DATAMATH CALCULATOR MUSEUM
Texas Instruments TI-58C Implant Power Calculation
|Date of introduction:||1982||Display technology:||LED-stick|
|New price:||Display size:||10 (8 + 2)|
|Size:|| 6.4" x 3.2" x
162 x 81 x 37 mm3
|Weight:||8.5 ounces, 240 grams||Serial No:||8206713|
|Batteries:||BP1A||Date of manufacture:||wk 46 year 1981|
|AC-Adapter:||AC9131||Origin of manufacture:||USA (ATA)|
|Precision:||13||Integrated circuits:||TMC0501E, TMC0591, CD2400, CD2401 TMC0573, TC5047|
|Program steps:||480-0||Courtesy of:||Joerg Woerner|
Shortly after the TI-58 and TI-59 Programmable calculators were launched in May 1977, the first application specific solutions based on the Solid State Software Modules™ approach appeared on the market. Within just a few years a whole spectrum of different software modules were introduced: Payroll Computing, V/STOL Calculations, Pool Water Analysis, Screw Joint Calculations, Mud Hydraulics, Federal Income Taxes and dozens more.
The SRK™ module developed by Computational Technology, Inc., Illinois, was used to calculate the power of intraocular lenses. An intraocular lens (IOL) is an implant in the human eye to replace the existing crystalline lens, or to change the eye's optical power. Sanders, Retzlaff, and Kraff developed in 1980 a regression-based intraocular lens calculation formula, known as the SRK formula
that is with some modifications still in use today.
Dismantling this Implant Power Calculation / SRK calculator reveals a standard TI-58C calculator manufactured in Autumn 1981 in Abilene, Texas. Please notice that the printed circuit board (PCB) of the calculator was assembled in Canada.
SRK™ is a registered trademark of Computational Technology, Inc.
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© Joerg Woerner, November 10, 2009. No reprints without written permission.