Browse Prior Art Database

Integrated Laser Life Test and Characterization Date Management System

IP.com Disclosure Number: IPCOM000105710D
Original Publication Date: 1993-Sep-01
Included in the Prior Art Database: 2005-Mar-20
Document File: 4 page(s) / 142K

Publishing Venue

IBM

Related People

Harding, RF: AUTHOR [+2]

Abstract

During the past few years, experimental studies on the reliability of the semiconductor lasers in our laboratory have improved our understanding of the aging phenomenon in the laser characteristics. From these studies, an extensive data base has been established which enabled the development of high reliability and high performance fiber-optic data links for computers.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 40% of the total text.

Integrated Laser Life Test and Characterization Date Management System

      During the past few years, experimental studies on the
reliability of the semiconductor lasers in our laboratory have
improved our understanding of the aging phenomenon in the laser
characteristics.  From these studies, an extensive data base has been
established which enabled the development of high reliability and
high performance fiber-optic data links for computers.

      An on-line information system has been designed to manage the
vast amount of laser test data.  In this system, a station-indexing
method is used to permit an efficient referencing of the results.
The functional parameters of each type of laser can be analyzed in
terms of their statistical behavior at various stages of degradation.
A data handling methodology has been incorporated in this system to
maintain the originality of the life test data while saving the
modifications simultaneously.  Therefore, the prediction of the laser
lifetime can be performed efficiently and precisely.

DESCRIPTION - For computer data communication using fiber optics,
acceptable laser diodes are required to be highly reliable.  In order
to evaluate the reliability of such lasers the degradation of the
functional parameters are often studied by placing many devices on
accelerated aging tests for great lengths of time.  From these tests,
a large data base for the lasers is obtained.  p.  An on-line
information system has been designed to store and analyze the laser
lifetest and characterization results.  This data management system
has the following features:
o  Native Test Hardware Data Redundancy

   Data collected from the life testers are saved in duplicate files
   using two magnetic disk storage media.  Such redundancies are
   critical to the operation of the test systems due to the fact that
   in the long term stress testing of the laser samples, magnetic
   disks used by the testers are also wearing out because of their
   full-time operation for several years.  Without an on-line backup
   storage, any disk failure is catastrophic to the integrity of the
   data base.
o  APL (A Programming Language)

   The data system is programmed in APL and resides in a host
   computer environment.  It consists of several APL "work spaces".
   An APL work space is dedicated to contain programs and all
   relevant test data for a given life tester.  The APL language is

   utilized due to its versatility in the development of analysis
   tools as well as its high efficiency in handling numerical and
   alphanumeric data.
o  Test Station Indexing

   Each of our 4 laser life testers consists of groups of test
   stations mounted on heat sinks with stabilized stress
   temperatures.  Many different types of lasers can be evaluated
   simultaneously on each tester.  At any given time, when a test
   station is occupied by a laser device, it is also identified in
 ...