LIVERMORE, Calif. (AP) _ The director of a program intended to build the world's most powerful lasers has resigned amid questions about his education.

E. Michael Campbell, associate director for lasers at Lawrence Livermore National Laboratory in Livermore, Calif., left his job Friday after a series of anonymous faxes to his bosses revealed he does not have a Ph.D.

However, he said he was leaving for personal reasons.

``I have a young family, and I need to spend some time with them,'' he told the Contra Costa Times. ``My wife has said the lab has sucked the life out of me.''

One of the world's leading authorities on ultra-high-energy lasers, Campbell remains an employee on leave from the lab, a spokesman said.

Campbell was director of a $1.2 billion program to build the National Ignition Facility, intended to conduct research in weapons and fusion.

Lab spokesman Jeff Richardson said Campbell had allowed lab officials to believe he had a doctorate from Princeton University.

``Mike had completed his Ph.D. course work when he joined Livermore in 1977, but he never finished his dissertation,'' Richardson said.

Lab officials were investigating whether he lied about holding a doctorate during the hiring process. They said they are unlikely to release the results of their investigation because it is a personnel issue.

Campbell said the need for a doctorate became increasingly insignificant as he made a rapid rise through the lab's laser fusion programs.

Campbell's supporters say it's a common practice to hire scientists who have not yet completed their dissertations.

``It would be a waste of time and talent to continue to pursue a dissertation in some cases,'' said David Crandall, a Department of Energy official overseeing the laser project.

However, the lab requires each senior manager to hold a Ph.D. or its equivalent in experience. The lab's former director, John Nuckolls, also did not have a Ph.D.

Calls to laboratory representatives for additional comment today were not returned. Campbell's home telephone number is unlisted.